1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2019 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
22 #include "gdbsupport/agent.h"
24 #include "gdbsupport/rsp-low.h"
25 #include "gdbsupport/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdbsupport/gdb_wait.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "gdbsupport/filestuff.h"
47 #include "tracepoint.h"
50 #include "gdbsupport/common-inferior.h"
51 #include "nat/fork-inferior.h"
52 #include "gdbsupport/environ.h"
53 #include "gdbsupport/scoped_restore.h"
55 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
56 then ELFMAG0 will have been defined. If it didn't get included by
57 gdb_proc_service.h then including it will likely introduce a duplicate
58 definition of elf_fpregset_t. */
61 #include "nat/linux-namespaces.h"
64 #define SPUFS_MAGIC 0x23c9b64e
67 #ifdef HAVE_PERSONALITY
68 # include <sys/personality.h>
69 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
70 # define ADDR_NO_RANDOMIZE 0x0040000
82 /* Some targets did not define these ptrace constants from the start,
83 so gdbserver defines them locally here. In the future, these may
84 be removed after they are added to asm/ptrace.h. */
85 #if !(defined(PT_TEXT_ADDR) \
86 || defined(PT_DATA_ADDR) \
87 || defined(PT_TEXT_END_ADDR))
88 #if defined(__mcoldfire__)
89 /* These are still undefined in 3.10 kernels. */
90 #define PT_TEXT_ADDR 49*4
91 #define PT_DATA_ADDR 50*4
92 #define PT_TEXT_END_ADDR 51*4
93 /* BFIN already defines these since at least 2.6.32 kernels. */
95 #define PT_TEXT_ADDR 220
96 #define PT_TEXT_END_ADDR 224
97 #define PT_DATA_ADDR 228
98 /* These are still undefined in 3.10 kernels. */
99 #elif defined(__TMS320C6X__)
100 #define PT_TEXT_ADDR (0x10000*4)
101 #define PT_DATA_ADDR (0x10004*4)
102 #define PT_TEXT_END_ADDR (0x10008*4)
106 #ifdef HAVE_LINUX_BTRACE
107 # include "nat/linux-btrace.h"
108 # include "gdbsupport/btrace-common.h"
111 #ifndef HAVE_ELF32_AUXV_T
112 /* Copied from glibc's elf.h. */
115 uint32_t a_type
; /* Entry type */
118 uint32_t a_val
; /* Integer value */
119 /* We use to have pointer elements added here. We cannot do that,
120 though, since it does not work when using 32-bit definitions
121 on 64-bit platforms and vice versa. */
126 #ifndef HAVE_ELF64_AUXV_T
127 /* Copied from glibc's elf.h. */
130 uint64_t a_type
; /* Entry type */
133 uint64_t a_val
; /* Integer value */
134 /* We use to have pointer elements added here. We cannot do that,
135 though, since it does not work when using 32-bit definitions
136 on 64-bit platforms and vice versa. */
141 /* Does the current host support PTRACE_GETREGSET? */
142 int have_ptrace_getregset
= -1;
146 /* See nat/linux-nat.h. */
149 ptid_of_lwp (struct lwp_info
*lwp
)
151 return ptid_of (get_lwp_thread (lwp
));
154 /* See nat/linux-nat.h. */
157 lwp_set_arch_private_info (struct lwp_info
*lwp
,
158 struct arch_lwp_info
*info
)
160 lwp
->arch_private
= info
;
163 /* See nat/linux-nat.h. */
165 struct arch_lwp_info
*
166 lwp_arch_private_info (struct lwp_info
*lwp
)
168 return lwp
->arch_private
;
171 /* See nat/linux-nat.h. */
174 lwp_is_stopped (struct lwp_info
*lwp
)
179 /* See nat/linux-nat.h. */
181 enum target_stop_reason
182 lwp_stop_reason (struct lwp_info
*lwp
)
184 return lwp
->stop_reason
;
187 /* See nat/linux-nat.h. */
190 lwp_is_stepping (struct lwp_info
*lwp
)
192 return lwp
->stepping
;
195 /* A list of all unknown processes which receive stop signals. Some
196 other process will presumably claim each of these as forked
197 children momentarily. */
199 struct simple_pid_list
201 /* The process ID. */
204 /* The status as reported by waitpid. */
208 struct simple_pid_list
*next
;
210 struct simple_pid_list
*stopped_pids
;
212 /* Trivial list manipulation functions to keep track of a list of new
213 stopped processes. */
216 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
218 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
221 new_pid
->status
= status
;
222 new_pid
->next
= *listp
;
227 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
229 struct simple_pid_list
**p
;
231 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
232 if ((*p
)->pid
== pid
)
234 struct simple_pid_list
*next
= (*p
)->next
;
236 *statusp
= (*p
)->status
;
244 enum stopping_threads_kind
246 /* Not stopping threads presently. */
247 NOT_STOPPING_THREADS
,
249 /* Stopping threads. */
252 /* Stopping and suspending threads. */
253 STOPPING_AND_SUSPENDING_THREADS
256 /* This is set while stop_all_lwps is in effect. */
257 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
259 /* FIXME make into a target method? */
260 int using_threads
= 1;
262 /* True if we're presently stabilizing threads (moving them out of
264 static int stabilizing_threads
;
266 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
267 int step
, int signal
, siginfo_t
*info
);
268 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
269 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
270 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
271 static void unsuspend_all_lwps (struct lwp_info
*except
);
272 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
273 int *wstat
, int options
);
274 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
275 static struct lwp_info
*add_lwp (ptid_t ptid
);
276 static void linux_mourn (struct process_info
*process
);
277 static int linux_stopped_by_watchpoint (void);
278 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
279 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
280 static void proceed_all_lwps (void);
281 static int finish_step_over (struct lwp_info
*lwp
);
282 static int kill_lwp (unsigned long lwpid
, int signo
);
283 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
284 static void complete_ongoing_step_over (void);
285 static int linux_low_ptrace_options (int attached
);
286 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
287 static void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
289 /* When the event-loop is doing a step-over, this points at the thread
291 ptid_t step_over_bkpt
;
293 /* True if the low target can hardware single-step. */
296 can_hardware_single_step (void)
298 if (the_low_target
.supports_hardware_single_step
!= NULL
)
299 return the_low_target
.supports_hardware_single_step ();
304 /* True if the low target can software single-step. Such targets
305 implement the GET_NEXT_PCS callback. */
308 can_software_single_step (void)
310 return (the_low_target
.get_next_pcs
!= NULL
);
313 /* True if the low target supports memory breakpoints. If so, we'll
314 have a GET_PC implementation. */
317 supports_breakpoints (void)
319 return (the_low_target
.get_pc
!= NULL
);
322 /* Returns true if this target can support fast tracepoints. This
323 does not mean that the in-process agent has been loaded in the
327 supports_fast_tracepoints (void)
329 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
332 /* True if LWP is stopped in its stepping range. */
335 lwp_in_step_range (struct lwp_info
*lwp
)
337 CORE_ADDR pc
= lwp
->stop_pc
;
339 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
342 struct pending_signals
346 struct pending_signals
*prev
;
349 /* The read/write ends of the pipe registered as waitable file in the
351 static int linux_event_pipe
[2] = { -1, -1 };
353 /* True if we're currently in async mode. */
354 #define target_is_async_p() (linux_event_pipe[0] != -1)
356 static void send_sigstop (struct lwp_info
*lwp
);
357 static void wait_for_sigstop (void);
359 /* Return non-zero if HEADER is a 64-bit ELF file. */
362 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
364 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
365 && header
->e_ident
[EI_MAG1
] == ELFMAG1
366 && header
->e_ident
[EI_MAG2
] == ELFMAG2
367 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
369 *machine
= header
->e_machine
;
370 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
377 /* Return non-zero if FILE is a 64-bit ELF file,
378 zero if the file is not a 64-bit ELF file,
379 and -1 if the file is not accessible or doesn't exist. */
382 elf_64_file_p (const char *file
, unsigned int *machine
)
387 fd
= open (file
, O_RDONLY
);
391 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
398 return elf_64_header_p (&header
, machine
);
401 /* Accepts an integer PID; Returns true if the executable PID is
402 running is a 64-bit ELF file.. */
405 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
409 sprintf (file
, "/proc/%d/exe", pid
);
410 return elf_64_file_p (file
, machine
);
414 delete_lwp (struct lwp_info
*lwp
)
416 struct thread_info
*thr
= get_lwp_thread (lwp
);
419 debug_printf ("deleting %ld\n", lwpid_of (thr
));
423 if (the_low_target
.delete_thread
!= NULL
)
424 the_low_target
.delete_thread (lwp
->arch_private
);
426 gdb_assert (lwp
->arch_private
== NULL
);
431 /* Add a process to the common process list, and set its private
434 static struct process_info
*
435 linux_add_process (int pid
, int attached
)
437 struct process_info
*proc
;
439 proc
= add_process (pid
, attached
);
440 proc
->priv
= XCNEW (struct process_info_private
);
442 if (the_low_target
.new_process
!= NULL
)
443 proc
->priv
->arch_private
= the_low_target
.new_process ();
448 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
450 /* Call the target arch_setup function on the current thread. */
453 linux_arch_setup (void)
455 the_low_target
.arch_setup ();
458 /* Call the target arch_setup function on THREAD. */
461 linux_arch_setup_thread (struct thread_info
*thread
)
463 struct thread_info
*saved_thread
;
465 saved_thread
= current_thread
;
466 current_thread
= thread
;
470 current_thread
= saved_thread
;
473 /* Handle a GNU/Linux extended wait response. If we see a clone,
474 fork, or vfork event, we need to add the new LWP to our list
475 (and return 0 so as not to report the trap to higher layers).
476 If we see an exec event, we will modify ORIG_EVENT_LWP to point
477 to a new LWP representing the new program. */
480 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
482 client_state
&cs
= get_client_state ();
483 struct lwp_info
*event_lwp
= *orig_event_lwp
;
484 int event
= linux_ptrace_get_extended_event (wstat
);
485 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
486 struct lwp_info
*new_lwp
;
488 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
490 /* All extended events we currently use are mid-syscall. Only
491 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
492 you have to be using PTRACE_SEIZE to get that. */
493 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
495 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
496 || (event
== PTRACE_EVENT_CLONE
))
499 unsigned long new_pid
;
502 /* Get the pid of the new lwp. */
503 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
506 /* If we haven't already seen the new PID stop, wait for it now. */
507 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
509 /* The new child has a pending SIGSTOP. We can't affect it until it
510 hits the SIGSTOP, but we're already attached. */
512 ret
= my_waitpid (new_pid
, &status
, __WALL
);
515 perror_with_name ("waiting for new child");
516 else if (ret
!= new_pid
)
517 warning ("wait returned unexpected PID %d", ret
);
518 else if (!WIFSTOPPED (status
))
519 warning ("wait returned unexpected status 0x%x", status
);
522 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
524 struct process_info
*parent_proc
;
525 struct process_info
*child_proc
;
526 struct lwp_info
*child_lwp
;
527 struct thread_info
*child_thr
;
528 struct target_desc
*tdesc
;
530 ptid
= ptid_t (new_pid
, new_pid
, 0);
534 debug_printf ("HEW: Got fork event from LWP %ld, "
536 ptid_of (event_thr
).lwp (),
540 /* Add the new process to the tables and clone the breakpoint
541 lists of the parent. We need to do this even if the new process
542 will be detached, since we will need the process object and the
543 breakpoints to remove any breakpoints from memory when we
544 detach, and the client side will access registers. */
545 child_proc
= linux_add_process (new_pid
, 0);
546 gdb_assert (child_proc
!= NULL
);
547 child_lwp
= add_lwp (ptid
);
548 gdb_assert (child_lwp
!= NULL
);
549 child_lwp
->stopped
= 1;
550 child_lwp
->must_set_ptrace_flags
= 1;
551 child_lwp
->status_pending_p
= 0;
552 child_thr
= get_lwp_thread (child_lwp
);
553 child_thr
->last_resume_kind
= resume_stop
;
554 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
556 /* If we're suspending all threads, leave this one suspended
557 too. If the fork/clone parent is stepping over a breakpoint,
558 all other threads have been suspended already. Leave the
559 child suspended too. */
560 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
561 || event_lwp
->bp_reinsert
!= 0)
564 debug_printf ("HEW: leaving child suspended\n");
565 child_lwp
->suspended
= 1;
568 parent_proc
= get_thread_process (event_thr
);
569 child_proc
->attached
= parent_proc
->attached
;
571 if (event_lwp
->bp_reinsert
!= 0
572 && can_software_single_step ()
573 && event
== PTRACE_EVENT_VFORK
)
575 /* If we leave single-step breakpoints there, child will
576 hit it, so uninsert single-step breakpoints from parent
577 (and child). Once vfork child is done, reinsert
578 them back to parent. */
579 uninsert_single_step_breakpoints (event_thr
);
582 clone_all_breakpoints (child_thr
, event_thr
);
584 tdesc
= allocate_target_description ();
585 copy_target_description (tdesc
, parent_proc
->tdesc
);
586 child_proc
->tdesc
= tdesc
;
588 /* Clone arch-specific process data. */
589 if (the_low_target
.new_fork
!= NULL
)
590 the_low_target
.new_fork (parent_proc
, child_proc
);
592 /* Save fork info in the parent thread. */
593 if (event
== PTRACE_EVENT_FORK
)
594 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
595 else if (event
== PTRACE_EVENT_VFORK
)
596 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
598 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
600 /* The status_pending field contains bits denoting the
601 extended event, so when the pending event is handled,
602 the handler will look at lwp->waitstatus. */
603 event_lwp
->status_pending_p
= 1;
604 event_lwp
->status_pending
= wstat
;
606 /* Link the threads until the parent event is passed on to
608 event_lwp
->fork_relative
= child_lwp
;
609 child_lwp
->fork_relative
= event_lwp
;
611 /* If the parent thread is doing step-over with single-step
612 breakpoints, the list of single-step breakpoints are cloned
613 from the parent's. Remove them from the child process.
614 In case of vfork, we'll reinsert them back once vforked
616 if (event_lwp
->bp_reinsert
!= 0
617 && can_software_single_step ())
619 /* The child process is forked and stopped, so it is safe
620 to access its memory without stopping all other threads
621 from other processes. */
622 delete_single_step_breakpoints (child_thr
);
624 gdb_assert (has_single_step_breakpoints (event_thr
));
625 gdb_assert (!has_single_step_breakpoints (child_thr
));
628 /* Report the event. */
633 debug_printf ("HEW: Got clone event "
634 "from LWP %ld, new child is LWP %ld\n",
635 lwpid_of (event_thr
), new_pid
);
637 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
638 new_lwp
= add_lwp (ptid
);
640 /* Either we're going to immediately resume the new thread
641 or leave it stopped. linux_resume_one_lwp is a nop if it
642 thinks the thread is currently running, so set this first
643 before calling linux_resume_one_lwp. */
644 new_lwp
->stopped
= 1;
646 /* If we're suspending all threads, leave this one suspended
647 too. If the fork/clone parent is stepping over a breakpoint,
648 all other threads have been suspended already. Leave the
649 child suspended too. */
650 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
651 || event_lwp
->bp_reinsert
!= 0)
652 new_lwp
->suspended
= 1;
654 /* Normally we will get the pending SIGSTOP. But in some cases
655 we might get another signal delivered to the group first.
656 If we do get another signal, be sure not to lose it. */
657 if (WSTOPSIG (status
) != SIGSTOP
)
659 new_lwp
->stop_expected
= 1;
660 new_lwp
->status_pending_p
= 1;
661 new_lwp
->status_pending
= status
;
663 else if (cs
.report_thread_events
)
665 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
666 new_lwp
->status_pending_p
= 1;
667 new_lwp
->status_pending
= status
;
671 thread_db_notice_clone (event_thr
, ptid
);
674 /* Don't report the event. */
677 else if (event
== PTRACE_EVENT_VFORK_DONE
)
679 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
681 if (event_lwp
->bp_reinsert
!= 0 && can_software_single_step ())
683 reinsert_single_step_breakpoints (event_thr
);
685 gdb_assert (has_single_step_breakpoints (event_thr
));
688 /* Report the event. */
691 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
693 struct process_info
*proc
;
694 std::vector
<int> syscalls_to_catch
;
700 debug_printf ("HEW: Got exec event from LWP %ld\n",
701 lwpid_of (event_thr
));
704 /* Get the event ptid. */
705 event_ptid
= ptid_of (event_thr
);
706 event_pid
= event_ptid
.pid ();
708 /* Save the syscall list from the execing process. */
709 proc
= get_thread_process (event_thr
);
710 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
712 /* Delete the execing process and all its threads. */
714 current_thread
= NULL
;
716 /* Create a new process/lwp/thread. */
717 proc
= linux_add_process (event_pid
, 0);
718 event_lwp
= add_lwp (event_ptid
);
719 event_thr
= get_lwp_thread (event_lwp
);
720 gdb_assert (current_thread
== event_thr
);
721 linux_arch_setup_thread (event_thr
);
723 /* Set the event status. */
724 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
725 event_lwp
->waitstatus
.value
.execd_pathname
726 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
728 /* Mark the exec status as pending. */
729 event_lwp
->stopped
= 1;
730 event_lwp
->status_pending_p
= 1;
731 event_lwp
->status_pending
= wstat
;
732 event_thr
->last_resume_kind
= resume_continue
;
733 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
735 /* Update syscall state in the new lwp, effectively mid-syscall too. */
736 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
738 /* Restore the list to catch. Don't rely on the client, which is free
739 to avoid sending a new list when the architecture doesn't change.
740 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
741 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
743 /* Report the event. */
744 *orig_event_lwp
= event_lwp
;
748 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
751 /* Return the PC as read from the regcache of LWP, without any
755 get_pc (struct lwp_info
*lwp
)
757 struct thread_info
*saved_thread
;
758 struct regcache
*regcache
;
761 if (the_low_target
.get_pc
== NULL
)
764 saved_thread
= current_thread
;
765 current_thread
= get_lwp_thread (lwp
);
767 regcache
= get_thread_regcache (current_thread
, 1);
768 pc
= (*the_low_target
.get_pc
) (regcache
);
771 debug_printf ("pc is 0x%lx\n", (long) pc
);
773 current_thread
= saved_thread
;
777 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
778 Fill *SYSNO with the syscall nr trapped. */
781 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
)
783 struct thread_info
*saved_thread
;
784 struct regcache
*regcache
;
786 if (the_low_target
.get_syscall_trapinfo
== NULL
)
788 /* If we cannot get the syscall trapinfo, report an unknown
789 system call number. */
790 *sysno
= UNKNOWN_SYSCALL
;
794 saved_thread
= current_thread
;
795 current_thread
= get_lwp_thread (lwp
);
797 regcache
= get_thread_regcache (current_thread
, 1);
798 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
);
801 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
803 current_thread
= saved_thread
;
806 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
808 /* Called when the LWP stopped for a signal/trap. If it stopped for a
809 trap check what caused it (breakpoint, watchpoint, trace, etc.),
810 and save the result in the LWP's stop_reason field. If it stopped
811 for a breakpoint, decrement the PC if necessary on the lwp's
812 architecture. Returns true if we now have the LWP's stop PC. */
815 save_stop_reason (struct lwp_info
*lwp
)
818 CORE_ADDR sw_breakpoint_pc
;
819 struct thread_info
*saved_thread
;
820 #if USE_SIGTRAP_SIGINFO
824 if (the_low_target
.get_pc
== NULL
)
828 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
830 /* breakpoint_at reads from the current thread. */
831 saved_thread
= current_thread
;
832 current_thread
= get_lwp_thread (lwp
);
834 #if USE_SIGTRAP_SIGINFO
835 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
836 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
838 if (siginfo
.si_signo
== SIGTRAP
)
840 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
841 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
843 /* The si_code is ambiguous on this arch -- check debug
845 if (!check_stopped_by_watchpoint (lwp
))
846 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
848 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
850 /* If we determine the LWP stopped for a SW breakpoint,
851 trust it. Particularly don't check watchpoint
852 registers, because at least on s390, we'd find
853 stopped-by-watchpoint as long as there's a watchpoint
855 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
857 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
859 /* This can indicate either a hardware breakpoint or
860 hardware watchpoint. Check debug registers. */
861 if (!check_stopped_by_watchpoint (lwp
))
862 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
864 else if (siginfo
.si_code
== TRAP_TRACE
)
866 /* We may have single stepped an instruction that
867 triggered a watchpoint. In that case, on some
868 architectures (such as x86), instead of TRAP_HWBKPT,
869 si_code indicates TRAP_TRACE, and we need to check
870 the debug registers separately. */
871 if (!check_stopped_by_watchpoint (lwp
))
872 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
877 /* We may have just stepped a breakpoint instruction. E.g., in
878 non-stop mode, GDB first tells the thread A to step a range, and
879 then the user inserts a breakpoint inside the range. In that
880 case we need to report the breakpoint PC. */
881 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
882 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
883 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
885 if (hardware_breakpoint_inserted_here (pc
))
886 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
888 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
889 check_stopped_by_watchpoint (lwp
);
892 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
896 struct thread_info
*thr
= get_lwp_thread (lwp
);
898 debug_printf ("CSBB: %s stopped by software breakpoint\n",
899 target_pid_to_str (ptid_of (thr
)));
902 /* Back up the PC if necessary. */
903 if (pc
!= sw_breakpoint_pc
)
905 struct regcache
*regcache
906 = get_thread_regcache (current_thread
, 1);
907 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
910 /* Update this so we record the correct stop PC below. */
911 pc
= sw_breakpoint_pc
;
913 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
917 struct thread_info
*thr
= get_lwp_thread (lwp
);
919 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
920 target_pid_to_str (ptid_of (thr
)));
923 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
927 struct thread_info
*thr
= get_lwp_thread (lwp
);
929 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
930 target_pid_to_str (ptid_of (thr
)));
933 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
937 struct thread_info
*thr
= get_lwp_thread (lwp
);
939 debug_printf ("CSBB: %s stopped by trace\n",
940 target_pid_to_str (ptid_of (thr
)));
945 current_thread
= saved_thread
;
949 static struct lwp_info
*
950 add_lwp (ptid_t ptid
)
952 struct lwp_info
*lwp
;
954 lwp
= XCNEW (struct lwp_info
);
956 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
958 lwp
->thread
= add_thread (ptid
, lwp
);
960 if (the_low_target
.new_thread
!= NULL
)
961 the_low_target
.new_thread (lwp
);
966 /* Callback to be used when calling fork_inferior, responsible for
967 actually initiating the tracing of the inferior. */
972 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
973 (PTRACE_TYPE_ARG4
) 0) < 0)
974 trace_start_error_with_name ("ptrace");
976 if (setpgid (0, 0) < 0)
977 trace_start_error_with_name ("setpgid");
979 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
980 stdout to stderr so that inferior i/o doesn't corrupt the connection.
981 Also, redirect stdin to /dev/null. */
982 if (remote_connection_is_stdio ())
985 trace_start_error_with_name ("close");
986 if (open ("/dev/null", O_RDONLY
) < 0)
987 trace_start_error_with_name ("open");
989 trace_start_error_with_name ("dup2");
990 if (write (2, "stdin/stdout redirected\n",
991 sizeof ("stdin/stdout redirected\n") - 1) < 0)
993 /* Errors ignored. */;
998 /* Start an inferior process and returns its pid.
999 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
1000 are its arguments. */
1003 linux_create_inferior (const char *program
,
1004 const std::vector
<char *> &program_args
)
1006 client_state
&cs
= get_client_state ();
1007 struct lwp_info
*new_lwp
;
1012 maybe_disable_address_space_randomization restore_personality
1013 (cs
.disable_randomization
);
1014 std::string str_program_args
= stringify_argv (program_args
);
1016 pid
= fork_inferior (program
,
1017 str_program_args
.c_str (),
1018 get_environ ()->envp (), linux_ptrace_fun
,
1019 NULL
, NULL
, NULL
, NULL
);
1022 linux_add_process (pid
, 0);
1024 ptid
= ptid_t (pid
, pid
, 0);
1025 new_lwp
= add_lwp (ptid
);
1026 new_lwp
->must_set_ptrace_flags
= 1;
1028 post_fork_inferior (pid
, program
);
1033 /* Implement the post_create_inferior target_ops method. */
1036 linux_post_create_inferior (void)
1038 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1040 linux_arch_setup ();
1042 if (lwp
->must_set_ptrace_flags
)
1044 struct process_info
*proc
= current_process ();
1045 int options
= linux_low_ptrace_options (proc
->attached
);
1047 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1048 lwp
->must_set_ptrace_flags
= 0;
1052 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1056 linux_attach_lwp (ptid_t ptid
)
1058 struct lwp_info
*new_lwp
;
1059 int lwpid
= ptid
.lwp ();
1061 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1065 new_lwp
= add_lwp (ptid
);
1067 /* We need to wait for SIGSTOP before being able to make the next
1068 ptrace call on this LWP. */
1069 new_lwp
->must_set_ptrace_flags
= 1;
1071 if (linux_proc_pid_is_stopped (lwpid
))
1074 debug_printf ("Attached to a stopped process\n");
1076 /* The process is definitely stopped. It is in a job control
1077 stop, unless the kernel predates the TASK_STOPPED /
1078 TASK_TRACED distinction, in which case it might be in a
1079 ptrace stop. Make sure it is in a ptrace stop; from there we
1080 can kill it, signal it, et cetera.
1082 First make sure there is a pending SIGSTOP. Since we are
1083 already attached, the process can not transition from stopped
1084 to running without a PTRACE_CONT; so we know this signal will
1085 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1086 probably already in the queue (unless this kernel is old
1087 enough to use TASK_STOPPED for ptrace stops); but since
1088 SIGSTOP is not an RT signal, it can only be queued once. */
1089 kill_lwp (lwpid
, SIGSTOP
);
1091 /* Finally, resume the stopped process. This will deliver the
1092 SIGSTOP (or a higher priority signal, just like normal
1093 PTRACE_ATTACH), which we'll catch later on. */
1094 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1097 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1098 brings it to a halt.
1100 There are several cases to consider here:
1102 1) gdbserver has already attached to the process and is being notified
1103 of a new thread that is being created.
1104 In this case we should ignore that SIGSTOP and resume the
1105 process. This is handled below by setting stop_expected = 1,
1106 and the fact that add_thread sets last_resume_kind ==
1109 2) This is the first thread (the process thread), and we're attaching
1110 to it via attach_inferior.
1111 In this case we want the process thread to stop.
1112 This is handled by having linux_attach set last_resume_kind ==
1113 resume_stop after we return.
1115 If the pid we are attaching to is also the tgid, we attach to and
1116 stop all the existing threads. Otherwise, we attach to pid and
1117 ignore any other threads in the same group as this pid.
1119 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1121 In this case we want the thread to stop.
1122 FIXME: This case is currently not properly handled.
1123 We should wait for the SIGSTOP but don't. Things work apparently
1124 because enough time passes between when we ptrace (ATTACH) and when
1125 gdb makes the next ptrace call on the thread.
1127 On the other hand, if we are currently trying to stop all threads, we
1128 should treat the new thread as if we had sent it a SIGSTOP. This works
1129 because we are guaranteed that the add_lwp call above added us to the
1130 end of the list, and so the new thread has not yet reached
1131 wait_for_sigstop (but will). */
1132 new_lwp
->stop_expected
= 1;
1137 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1138 already attached. Returns true if a new LWP is found, false
1142 attach_proc_task_lwp_callback (ptid_t ptid
)
1144 /* Is this a new thread? */
1145 if (find_thread_ptid (ptid
) == NULL
)
1147 int lwpid
= ptid
.lwp ();
1151 debug_printf ("Found new lwp %d\n", lwpid
);
1153 err
= linux_attach_lwp (ptid
);
1155 /* Be quiet if we simply raced with the thread exiting. EPERM
1156 is returned if the thread's task still exists, and is marked
1157 as exited or zombie, as well as other conditions, so in that
1158 case, confirm the status in /proc/PID/status. */
1160 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1164 debug_printf ("Cannot attach to lwp %d: "
1165 "thread is gone (%d: %s)\n",
1166 lwpid
, err
, strerror (err
));
1172 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1174 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1182 static void async_file_mark (void);
1184 /* Attach to PID. If PID is the tgid, attach to it and all
1188 linux_attach (unsigned long pid
)
1190 struct process_info
*proc
;
1191 struct thread_info
*initial_thread
;
1192 ptid_t ptid
= ptid_t (pid
, pid
, 0);
1195 proc
= linux_add_process (pid
, 1);
1197 /* Attach to PID. We will check for other threads
1199 err
= linux_attach_lwp (ptid
);
1202 remove_process (proc
);
1204 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1205 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1208 /* Don't ignore the initial SIGSTOP if we just attached to this
1209 process. It will be collected by wait shortly. */
1210 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
, 0));
1211 initial_thread
->last_resume_kind
= resume_stop
;
1213 /* We must attach to every LWP. If /proc is mounted, use that to
1214 find them now. On the one hand, the inferior may be using raw
1215 clone instead of using pthreads. On the other hand, even if it
1216 is using pthreads, GDB may not be connected yet (thread_db needs
1217 to do symbol lookups, through qSymbol). Also, thread_db walks
1218 structures in the inferior's address space to find the list of
1219 threads/LWPs, and those structures may well be corrupted. Note
1220 that once thread_db is loaded, we'll still use it to list threads
1221 and associate pthread info with each LWP. */
1222 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1224 /* GDB will shortly read the xml target description for this
1225 process, to figure out the process' architecture. But the target
1226 description is only filled in when the first process/thread in
1227 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1228 that now, otherwise, if GDB is fast enough, it could read the
1229 target description _before_ that initial stop. */
1232 struct lwp_info
*lwp
;
1234 ptid_t pid_ptid
= ptid_t (pid
);
1236 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1238 gdb_assert (lwpid
> 0);
1240 lwp
= find_lwp_pid (ptid_t (lwpid
));
1242 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1244 lwp
->status_pending_p
= 1;
1245 lwp
->status_pending
= wstat
;
1248 initial_thread
->last_resume_kind
= resume_continue
;
1252 gdb_assert (proc
->tdesc
!= NULL
);
1259 last_thread_of_process_p (int pid
)
1261 bool seen_one
= false;
1263 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1267 /* This is the first thread of this process we see. */
1273 /* This is the second thread of this process we see. */
1278 return thread
== NULL
;
1284 linux_kill_one_lwp (struct lwp_info
*lwp
)
1286 struct thread_info
*thr
= get_lwp_thread (lwp
);
1287 int pid
= lwpid_of (thr
);
1289 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1290 there is no signal context, and ptrace(PTRACE_KILL) (or
1291 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1292 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1293 alternative is to kill with SIGKILL. We only need one SIGKILL
1294 per process, not one for each thread. But since we still support
1295 support debugging programs using raw clone without CLONE_THREAD,
1296 we send one for each thread. For years, we used PTRACE_KILL
1297 only, so we're being a bit paranoid about some old kernels where
1298 PTRACE_KILL might work better (dubious if there are any such, but
1299 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1300 second, and so we're fine everywhere. */
1303 kill_lwp (pid
, SIGKILL
);
1306 int save_errno
= errno
;
1308 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1309 target_pid_to_str (ptid_of (thr
)),
1310 save_errno
? strerror (save_errno
) : "OK");
1314 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1317 int save_errno
= errno
;
1319 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1320 target_pid_to_str (ptid_of (thr
)),
1321 save_errno
? strerror (save_errno
) : "OK");
1325 /* Kill LWP and wait for it to die. */
1328 kill_wait_lwp (struct lwp_info
*lwp
)
1330 struct thread_info
*thr
= get_lwp_thread (lwp
);
1331 int pid
= ptid_of (thr
).pid ();
1332 int lwpid
= ptid_of (thr
).lwp ();
1337 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1341 linux_kill_one_lwp (lwp
);
1343 /* Make sure it died. Notes:
1345 - The loop is most likely unnecessary.
1347 - We don't use linux_wait_for_event as that could delete lwps
1348 while we're iterating over them. We're not interested in
1349 any pending status at this point, only in making sure all
1350 wait status on the kernel side are collected until the
1353 - We don't use __WALL here as the __WALL emulation relies on
1354 SIGCHLD, and killing a stopped process doesn't generate
1355 one, nor an exit status.
1357 res
= my_waitpid (lwpid
, &wstat
, 0);
1358 if (res
== -1 && errno
== ECHILD
)
1359 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1360 } while (res
> 0 && WIFSTOPPED (wstat
));
1362 /* Even if it was stopped, the child may have already disappeared.
1363 E.g., if it was killed by SIGKILL. */
1364 if (res
< 0 && errno
!= ECHILD
)
1365 perror_with_name ("kill_wait_lwp");
1368 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1369 except the leader. */
1372 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1374 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1376 /* We avoid killing the first thread here, because of a Linux kernel (at
1377 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1378 the children get a chance to be reaped, it will remain a zombie
1381 if (lwpid_of (thread
) == pid
)
1384 debug_printf ("lkop: is last of process %s\n",
1385 target_pid_to_str (thread
->id
));
1389 kill_wait_lwp (lwp
);
1393 linux_kill (process_info
*process
)
1395 int pid
= process
->pid
;
1397 /* If we're killing a running inferior, make sure it is stopped
1398 first, as PTRACE_KILL will not work otherwise. */
1399 stop_all_lwps (0, NULL
);
1401 for_each_thread (pid
, [&] (thread_info
*thread
)
1403 kill_one_lwp_callback (thread
, pid
);
1406 /* See the comment in linux_kill_one_lwp. We did not kill the first
1407 thread in the list, so do so now. */
1408 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1413 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1417 kill_wait_lwp (lwp
);
1419 the_target
->mourn (process
);
1421 /* Since we presently can only stop all lwps of all processes, we
1422 need to unstop lwps of other processes. */
1423 unstop_all_lwps (0, NULL
);
1427 /* Get pending signal of THREAD, for detaching purposes. This is the
1428 signal the thread last stopped for, which we need to deliver to the
1429 thread when detaching, otherwise, it'd be suppressed/lost. */
1432 get_detach_signal (struct thread_info
*thread
)
1434 client_state
&cs
= get_client_state ();
1435 enum gdb_signal signo
= GDB_SIGNAL_0
;
1437 struct lwp_info
*lp
= get_thread_lwp (thread
);
1439 if (lp
->status_pending_p
)
1440 status
= lp
->status_pending
;
1443 /* If the thread had been suspended by gdbserver, and it stopped
1444 cleanly, then it'll have stopped with SIGSTOP. But we don't
1445 want to deliver that SIGSTOP. */
1446 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1447 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1450 /* Otherwise, we may need to deliver the signal we
1452 status
= lp
->last_status
;
1455 if (!WIFSTOPPED (status
))
1458 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1459 target_pid_to_str (ptid_of (thread
)));
1463 /* Extended wait statuses aren't real SIGTRAPs. */
1464 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1467 debug_printf ("GPS: lwp %s had stopped with extended "
1468 "status: no pending signal\n",
1469 target_pid_to_str (ptid_of (thread
)));
1473 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1475 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1478 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1479 target_pid_to_str (ptid_of (thread
)),
1480 gdb_signal_to_string (signo
));
1483 else if (!cs
.program_signals_p
1484 /* If we have no way to know which signals GDB does not
1485 want to have passed to the program, assume
1486 SIGTRAP/SIGINT, which is GDB's default. */
1487 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1490 debug_printf ("GPS: lwp %s had signal %s, "
1491 "but we don't know if we should pass it. "
1492 "Default to not.\n",
1493 target_pid_to_str (ptid_of (thread
)),
1494 gdb_signal_to_string (signo
));
1500 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1501 target_pid_to_str (ptid_of (thread
)),
1502 gdb_signal_to_string (signo
));
1504 return WSTOPSIG (status
);
1508 /* Detach from LWP. */
1511 linux_detach_one_lwp (struct lwp_info
*lwp
)
1513 struct thread_info
*thread
= get_lwp_thread (lwp
);
1517 /* If there is a pending SIGSTOP, get rid of it. */
1518 if (lwp
->stop_expected
)
1521 debug_printf ("Sending SIGCONT to %s\n",
1522 target_pid_to_str (ptid_of (thread
)));
1524 kill_lwp (lwpid_of (thread
), SIGCONT
);
1525 lwp
->stop_expected
= 0;
1528 /* Pass on any pending signal for this thread. */
1529 sig
= get_detach_signal (thread
);
1531 /* Preparing to resume may try to write registers, and fail if the
1532 lwp is zombie. If that happens, ignore the error. We'll handle
1533 it below, when detach fails with ESRCH. */
1536 /* Flush any pending changes to the process's registers. */
1537 regcache_invalidate_thread (thread
);
1539 /* Finally, let it resume. */
1540 if (the_low_target
.prepare_to_resume
!= NULL
)
1541 the_low_target
.prepare_to_resume (lwp
);
1543 catch (const gdb_exception_error
&ex
)
1545 if (!check_ptrace_stopped_lwp_gone (lwp
))
1549 lwpid
= lwpid_of (thread
);
1550 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1551 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1553 int save_errno
= errno
;
1555 /* We know the thread exists, so ESRCH must mean the lwp is
1556 zombie. This can happen if one of the already-detached
1557 threads exits the whole thread group. In that case we're
1558 still attached, and must reap the lwp. */
1559 if (save_errno
== ESRCH
)
1563 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1566 warning (_("Couldn't reap LWP %d while detaching: %s"),
1567 lwpid
, strerror (errno
));
1569 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1571 warning (_("Reaping LWP %d while detaching "
1572 "returned unexpected status 0x%x"),
1578 error (_("Can't detach %s: %s"),
1579 target_pid_to_str (ptid_of (thread
)),
1580 strerror (save_errno
));
1583 else if (debug_threads
)
1585 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1586 target_pid_to_str (ptid_of (thread
)),
1593 /* Callback for for_each_thread. Detaches from non-leader threads of a
1597 linux_detach_lwp_callback (thread_info
*thread
)
1599 /* We don't actually detach from the thread group leader just yet.
1600 If the thread group exits, we must reap the zombie clone lwps
1601 before we're able to reap the leader. */
1602 if (thread
->id
.pid () == thread
->id
.lwp ())
1605 lwp_info
*lwp
= get_thread_lwp (thread
);
1606 linux_detach_one_lwp (lwp
);
1610 linux_detach (process_info
*process
)
1612 struct lwp_info
*main_lwp
;
1614 /* As there's a step over already in progress, let it finish first,
1615 otherwise nesting a stabilize_threads operation on top gets real
1617 complete_ongoing_step_over ();
1619 /* Stop all threads before detaching. First, ptrace requires that
1620 the thread is stopped to sucessfully detach. Second, thread_db
1621 may need to uninstall thread event breakpoints from memory, which
1622 only works with a stopped process anyway. */
1623 stop_all_lwps (0, NULL
);
1625 #ifdef USE_THREAD_DB
1626 thread_db_detach (process
);
1629 /* Stabilize threads (move out of jump pads). */
1630 stabilize_threads ();
1632 /* Detach from the clone lwps first. If the thread group exits just
1633 while we're detaching, we must reap the clone lwps before we're
1634 able to reap the leader. */
1635 for_each_thread (process
->pid
, linux_detach_lwp_callback
);
1637 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1638 linux_detach_one_lwp (main_lwp
);
1640 the_target
->mourn (process
);
1642 /* Since we presently can only stop all lwps of all processes, we
1643 need to unstop lwps of other processes. */
1644 unstop_all_lwps (0, NULL
);
1648 /* Remove all LWPs that belong to process PROC from the lwp list. */
1651 linux_mourn (struct process_info
*process
)
1653 struct process_info_private
*priv
;
1655 #ifdef USE_THREAD_DB
1656 thread_db_mourn (process
);
1659 for_each_thread (process
->pid
, [] (thread_info
*thread
)
1661 delete_lwp (get_thread_lwp (thread
));
1664 /* Freeing all private data. */
1665 priv
= process
->priv
;
1666 if (the_low_target
.delete_process
!= NULL
)
1667 the_low_target
.delete_process (priv
->arch_private
);
1669 gdb_assert (priv
->arch_private
== NULL
);
1671 process
->priv
= NULL
;
1673 remove_process (process
);
1677 linux_join (int pid
)
1682 ret
= my_waitpid (pid
, &status
, 0);
1683 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1685 } while (ret
!= -1 || errno
!= ECHILD
);
1688 /* Return nonzero if the given thread is still alive. */
1690 linux_thread_alive (ptid_t ptid
)
1692 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1694 /* We assume we always know if a thread exits. If a whole process
1695 exited but we still haven't been able to report it to GDB, we'll
1696 hold on to the last lwp of the dead process. */
1698 return !lwp_is_marked_dead (lwp
);
1703 /* Return 1 if this lwp still has an interesting status pending. If
1704 not (e.g., it had stopped for a breakpoint that is gone), return
1708 thread_still_has_status_pending_p (struct thread_info
*thread
)
1710 struct lwp_info
*lp
= get_thread_lwp (thread
);
1712 if (!lp
->status_pending_p
)
1715 if (thread
->last_resume_kind
!= resume_stop
1716 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1717 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1719 struct thread_info
*saved_thread
;
1723 gdb_assert (lp
->last_status
!= 0);
1727 saved_thread
= current_thread
;
1728 current_thread
= thread
;
1730 if (pc
!= lp
->stop_pc
)
1733 debug_printf ("PC of %ld changed\n",
1738 #if !USE_SIGTRAP_SIGINFO
1739 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1740 && !(*the_low_target
.breakpoint_at
) (pc
))
1743 debug_printf ("previous SW breakpoint of %ld gone\n",
1747 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1748 && !hardware_breakpoint_inserted_here (pc
))
1751 debug_printf ("previous HW breakpoint of %ld gone\n",
1757 current_thread
= saved_thread
;
1762 debug_printf ("discarding pending breakpoint status\n");
1763 lp
->status_pending_p
= 0;
1771 /* Returns true if LWP is resumed from the client's perspective. */
1774 lwp_resumed (struct lwp_info
*lwp
)
1776 struct thread_info
*thread
= get_lwp_thread (lwp
);
1778 if (thread
->last_resume_kind
!= resume_stop
)
1781 /* Did gdb send us a `vCont;t', but we haven't reported the
1782 corresponding stop to gdb yet? If so, the thread is still
1783 resumed/running from gdb's perspective. */
1784 if (thread
->last_resume_kind
== resume_stop
1785 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1791 /* Return true if this lwp has an interesting status pending. */
1793 status_pending_p_callback (thread_info
*thread
, ptid_t ptid
)
1795 struct lwp_info
*lp
= get_thread_lwp (thread
);
1797 /* Check if we're only interested in events from a specific process
1798 or a specific LWP. */
1799 if (!thread
->id
.matches (ptid
))
1802 if (!lwp_resumed (lp
))
1805 if (lp
->status_pending_p
1806 && !thread_still_has_status_pending_p (thread
))
1808 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1812 return lp
->status_pending_p
;
1816 find_lwp_pid (ptid_t ptid
)
1818 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1820 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1821 return thr_arg
->id
.lwp () == lwp
;
1827 return get_thread_lwp (thread
);
1830 /* Return the number of known LWPs in the tgid given by PID. */
1837 for_each_thread (pid
, [&] (thread_info
*thread
)
1845 /* See nat/linux-nat.h. */
1848 iterate_over_lwps (ptid_t filter
,
1849 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1851 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1853 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1855 return callback (lwp
);
1861 return get_thread_lwp (thread
);
1864 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1865 their exits until all other threads in the group have exited. */
1868 check_zombie_leaders (void)
1870 for_each_process ([] (process_info
*proc
) {
1871 pid_t leader_pid
= pid_of (proc
);
1872 struct lwp_info
*leader_lp
;
1874 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1877 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1878 "num_lwps=%d, zombie=%d\n",
1879 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1880 linux_proc_pid_is_zombie (leader_pid
));
1882 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1883 /* Check if there are other threads in the group, as we may
1884 have raced with the inferior simply exiting. */
1885 && !last_thread_of_process_p (leader_pid
)
1886 && linux_proc_pid_is_zombie (leader_pid
))
1888 /* A leader zombie can mean one of two things:
1890 - It exited, and there's an exit status pending
1891 available, or only the leader exited (not the whole
1892 program). In the latter case, we can't waitpid the
1893 leader's exit status until all other threads are gone.
1895 - There are 3 or more threads in the group, and a thread
1896 other than the leader exec'd. On an exec, the Linux
1897 kernel destroys all other threads (except the execing
1898 one) in the thread group, and resets the execing thread's
1899 tid to the tgid. No exit notification is sent for the
1900 execing thread -- from the ptracer's perspective, it
1901 appears as though the execing thread just vanishes.
1902 Until we reap all other threads except the leader and the
1903 execing thread, the leader will be zombie, and the
1904 execing thread will be in `D (disc sleep)'. As soon as
1905 all other threads are reaped, the execing thread changes
1906 it's tid to the tgid, and the previous (zombie) leader
1907 vanishes, giving place to the "new" leader. We could try
1908 distinguishing the exit and exec cases, by waiting once
1909 more, and seeing if something comes out, but it doesn't
1910 sound useful. The previous leader _does_ go away, and
1911 we'll re-add the new one once we see the exec event
1912 (which is just the same as what would happen if the
1913 previous leader did exit voluntarily before some other
1917 debug_printf ("CZL: Thread group leader %d zombie "
1918 "(it exited, or another thread execd).\n",
1921 delete_lwp (leader_lp
);
1926 /* Callback for `find_thread'. Returns the first LWP that is not
1930 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1932 if (!thread
->id
.matches (filter
))
1935 lwp_info
*lwp
= get_thread_lwp (thread
);
1937 return !lwp
->stopped
;
1940 /* Increment LWP's suspend count. */
1943 lwp_suspended_inc (struct lwp_info
*lwp
)
1947 if (debug_threads
&& lwp
->suspended
> 4)
1949 struct thread_info
*thread
= get_lwp_thread (lwp
);
1951 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1952 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1956 /* Decrement LWP's suspend count. */
1959 lwp_suspended_decr (struct lwp_info
*lwp
)
1963 if (lwp
->suspended
< 0)
1965 struct thread_info
*thread
= get_lwp_thread (lwp
);
1967 internal_error (__FILE__
, __LINE__
,
1968 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1973 /* This function should only be called if the LWP got a SIGTRAP.
1975 Handle any tracepoint steps or hits. Return true if a tracepoint
1976 event was handled, 0 otherwise. */
1979 handle_tracepoints (struct lwp_info
*lwp
)
1981 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1982 int tpoint_related_event
= 0;
1984 gdb_assert (lwp
->suspended
== 0);
1986 /* If this tracepoint hit causes a tracing stop, we'll immediately
1987 uninsert tracepoints. To do this, we temporarily pause all
1988 threads, unpatch away, and then unpause threads. We need to make
1989 sure the unpausing doesn't resume LWP too. */
1990 lwp_suspended_inc (lwp
);
1992 /* And we need to be sure that any all-threads-stopping doesn't try
1993 to move threads out of the jump pads, as it could deadlock the
1994 inferior (LWP could be in the jump pad, maybe even holding the
1997 /* Do any necessary step collect actions. */
1998 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
2000 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
2002 /* See if we just hit a tracepoint and do its main collect
2004 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
2006 lwp_suspended_decr (lwp
);
2008 gdb_assert (lwp
->suspended
== 0);
2009 gdb_assert (!stabilizing_threads
2010 || (lwp
->collecting_fast_tracepoint
2011 != fast_tpoint_collect_result::not_collecting
));
2013 if (tpoint_related_event
)
2016 debug_printf ("got a tracepoint event\n");
2023 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2024 collection status. */
2026 static fast_tpoint_collect_result
2027 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
2028 struct fast_tpoint_collect_status
*status
)
2030 CORE_ADDR thread_area
;
2031 struct thread_info
*thread
= get_lwp_thread (lwp
);
2033 if (the_low_target
.get_thread_area
== NULL
)
2034 return fast_tpoint_collect_result::not_collecting
;
2036 /* Get the thread area address. This is used to recognize which
2037 thread is which when tracing with the in-process agent library.
2038 We don't read anything from the address, and treat it as opaque;
2039 it's the address itself that we assume is unique per-thread. */
2040 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
2041 return fast_tpoint_collect_result::not_collecting
;
2043 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
2046 /* The reason we resume in the caller, is because we want to be able
2047 to pass lwp->status_pending as WSTAT, and we need to clear
2048 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2049 refuses to resume. */
2052 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2054 struct thread_info
*saved_thread
;
2056 saved_thread
= current_thread
;
2057 current_thread
= get_lwp_thread (lwp
);
2060 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2061 && supports_fast_tracepoints ()
2062 && agent_loaded_p ())
2064 struct fast_tpoint_collect_status status
;
2067 debug_printf ("Checking whether LWP %ld needs to move out of the "
2069 lwpid_of (current_thread
));
2071 fast_tpoint_collect_result r
2072 = linux_fast_tracepoint_collecting (lwp
, &status
);
2075 || (WSTOPSIG (*wstat
) != SIGILL
2076 && WSTOPSIG (*wstat
) != SIGFPE
2077 && WSTOPSIG (*wstat
) != SIGSEGV
2078 && WSTOPSIG (*wstat
) != SIGBUS
))
2080 lwp
->collecting_fast_tracepoint
= r
;
2082 if (r
!= fast_tpoint_collect_result::not_collecting
)
2084 if (r
== fast_tpoint_collect_result::before_insn
2085 && lwp
->exit_jump_pad_bkpt
== NULL
)
2087 /* Haven't executed the original instruction yet.
2088 Set breakpoint there, and wait till it's hit,
2089 then single-step until exiting the jump pad. */
2090 lwp
->exit_jump_pad_bkpt
2091 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2095 debug_printf ("Checking whether LWP %ld needs to move out of "
2096 "the jump pad...it does\n",
2097 lwpid_of (current_thread
));
2098 current_thread
= saved_thread
;
2105 /* If we get a synchronous signal while collecting, *and*
2106 while executing the (relocated) original instruction,
2107 reset the PC to point at the tpoint address, before
2108 reporting to GDB. Otherwise, it's an IPA lib bug: just
2109 report the signal to GDB, and pray for the best. */
2111 lwp
->collecting_fast_tracepoint
2112 = fast_tpoint_collect_result::not_collecting
;
2114 if (r
!= fast_tpoint_collect_result::not_collecting
2115 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2116 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2119 struct regcache
*regcache
;
2121 /* The si_addr on a few signals references the address
2122 of the faulting instruction. Adjust that as
2124 if ((WSTOPSIG (*wstat
) == SIGILL
2125 || WSTOPSIG (*wstat
) == SIGFPE
2126 || WSTOPSIG (*wstat
) == SIGBUS
2127 || WSTOPSIG (*wstat
) == SIGSEGV
)
2128 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2129 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2130 /* Final check just to make sure we don't clobber
2131 the siginfo of non-kernel-sent signals. */
2132 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2134 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2135 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2136 (PTRACE_TYPE_ARG3
) 0, &info
);
2139 regcache
= get_thread_regcache (current_thread
, 1);
2140 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2141 lwp
->stop_pc
= status
.tpoint_addr
;
2143 /* Cancel any fast tracepoint lock this thread was
2145 force_unlock_trace_buffer ();
2148 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2151 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2152 "stopping all threads momentarily.\n");
2154 stop_all_lwps (1, lwp
);
2156 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2157 lwp
->exit_jump_pad_bkpt
= NULL
;
2159 unstop_all_lwps (1, lwp
);
2161 gdb_assert (lwp
->suspended
>= 0);
2167 debug_printf ("Checking whether LWP %ld needs to move out of the "
2169 lwpid_of (current_thread
));
2171 current_thread
= saved_thread
;
2175 /* Enqueue one signal in the "signals to report later when out of the
2179 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2181 struct pending_signals
*p_sig
;
2182 struct thread_info
*thread
= get_lwp_thread (lwp
);
2185 debug_printf ("Deferring signal %d for LWP %ld.\n",
2186 WSTOPSIG (*wstat
), lwpid_of (thread
));
2190 struct pending_signals
*sig
;
2192 for (sig
= lwp
->pending_signals_to_report
;
2195 debug_printf (" Already queued %d\n",
2198 debug_printf (" (no more currently queued signals)\n");
2201 /* Don't enqueue non-RT signals if they are already in the deferred
2202 queue. (SIGSTOP being the easiest signal to see ending up here
2204 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2206 struct pending_signals
*sig
;
2208 for (sig
= lwp
->pending_signals_to_report
;
2212 if (sig
->signal
== WSTOPSIG (*wstat
))
2215 debug_printf ("Not requeuing already queued non-RT signal %d"
2224 p_sig
= XCNEW (struct pending_signals
);
2225 p_sig
->prev
= lwp
->pending_signals_to_report
;
2226 p_sig
->signal
= WSTOPSIG (*wstat
);
2228 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2231 lwp
->pending_signals_to_report
= p_sig
;
2234 /* Dequeue one signal from the "signals to report later when out of
2235 the jump pad" list. */
2238 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2240 struct thread_info
*thread
= get_lwp_thread (lwp
);
2242 if (lwp
->pending_signals_to_report
!= NULL
)
2244 struct pending_signals
**p_sig
;
2246 p_sig
= &lwp
->pending_signals_to_report
;
2247 while ((*p_sig
)->prev
!= NULL
)
2248 p_sig
= &(*p_sig
)->prev
;
2250 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2251 if ((*p_sig
)->info
.si_signo
!= 0)
2252 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2258 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2259 WSTOPSIG (*wstat
), lwpid_of (thread
));
2263 struct pending_signals
*sig
;
2265 for (sig
= lwp
->pending_signals_to_report
;
2268 debug_printf (" Still queued %d\n",
2271 debug_printf (" (no more queued signals)\n");
2280 /* Fetch the possibly triggered data watchpoint info and store it in
2283 On some archs, like x86, that use debug registers to set
2284 watchpoints, it's possible that the way to know which watched
2285 address trapped, is to check the register that is used to select
2286 which address to watch. Problem is, between setting the watchpoint
2287 and reading back which data address trapped, the user may change
2288 the set of watchpoints, and, as a consequence, GDB changes the
2289 debug registers in the inferior. To avoid reading back a stale
2290 stopped-data-address when that happens, we cache in LP the fact
2291 that a watchpoint trapped, and the corresponding data address, as
2292 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2293 registers meanwhile, we have the cached data we can rely on. */
2296 check_stopped_by_watchpoint (struct lwp_info
*child
)
2298 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2300 struct thread_info
*saved_thread
;
2302 saved_thread
= current_thread
;
2303 current_thread
= get_lwp_thread (child
);
2305 if (the_low_target
.stopped_by_watchpoint ())
2307 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2309 if (the_low_target
.stopped_data_address
!= NULL
)
2310 child
->stopped_data_address
2311 = the_low_target
.stopped_data_address ();
2313 child
->stopped_data_address
= 0;
2316 current_thread
= saved_thread
;
2319 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2322 /* Return the ptrace options that we want to try to enable. */
2325 linux_low_ptrace_options (int attached
)
2327 client_state
&cs
= get_client_state ();
2331 options
|= PTRACE_O_EXITKILL
;
2333 if (cs
.report_fork_events
)
2334 options
|= PTRACE_O_TRACEFORK
;
2336 if (cs
.report_vfork_events
)
2337 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2339 if (cs
.report_exec_events
)
2340 options
|= PTRACE_O_TRACEEXEC
;
2342 options
|= PTRACE_O_TRACESYSGOOD
;
2347 /* Do low-level handling of the event, and check if we should go on
2348 and pass it to caller code. Return the affected lwp if we are, or
2351 static struct lwp_info
*
2352 linux_low_filter_event (int lwpid
, int wstat
)
2354 client_state
&cs
= get_client_state ();
2355 struct lwp_info
*child
;
2356 struct thread_info
*thread
;
2357 int have_stop_pc
= 0;
2359 child
= find_lwp_pid (ptid_t (lwpid
));
2361 /* Check for stop events reported by a process we didn't already
2362 know about - anything not already in our LWP list.
2364 If we're expecting to receive stopped processes after
2365 fork, vfork, and clone events, then we'll just add the
2366 new one to our list and go back to waiting for the event
2367 to be reported - the stopped process might be returned
2368 from waitpid before or after the event is.
2370 But note the case of a non-leader thread exec'ing after the
2371 leader having exited, and gone from our lists (because
2372 check_zombie_leaders deleted it). The non-leader thread
2373 changes its tid to the tgid. */
2375 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2376 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2380 /* A multi-thread exec after we had seen the leader exiting. */
2383 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2384 "after exec.\n", lwpid
);
2387 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2388 child
= add_lwp (child_ptid
);
2390 current_thread
= child
->thread
;
2393 /* If we didn't find a process, one of two things presumably happened:
2394 - A process we started and then detached from has exited. Ignore it.
2395 - A process we are controlling has forked and the new child's stop
2396 was reported to us by the kernel. Save its PID. */
2397 if (child
== NULL
&& WIFSTOPPED (wstat
))
2399 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2402 else if (child
== NULL
)
2405 thread
= get_lwp_thread (child
);
2409 child
->last_status
= wstat
;
2411 /* Check if the thread has exited. */
2412 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2415 debug_printf ("LLFE: %d exited.\n", lwpid
);
2417 if (finish_step_over (child
))
2419 /* Unsuspend all other LWPs, and set them back running again. */
2420 unsuspend_all_lwps (child
);
2423 /* If there is at least one more LWP, then the exit signal was
2424 not the end of the debugged application and should be
2425 ignored, unless GDB wants to hear about thread exits. */
2426 if (cs
.report_thread_events
2427 || last_thread_of_process_p (pid_of (thread
)))
2429 /* Since events are serialized to GDB core, and we can't
2430 report this one right now. Leave the status pending for
2431 the next time we're able to report it. */
2432 mark_lwp_dead (child
, wstat
);
2442 gdb_assert (WIFSTOPPED (wstat
));
2444 if (WIFSTOPPED (wstat
))
2446 struct process_info
*proc
;
2448 /* Architecture-specific setup after inferior is running. */
2449 proc
= find_process_pid (pid_of (thread
));
2450 if (proc
->tdesc
== NULL
)
2454 /* This needs to happen after we have attached to the
2455 inferior and it is stopped for the first time, but
2456 before we access any inferior registers. */
2457 linux_arch_setup_thread (thread
);
2461 /* The process is started, but GDBserver will do
2462 architecture-specific setup after the program stops at
2463 the first instruction. */
2464 child
->status_pending_p
= 1;
2465 child
->status_pending
= wstat
;
2471 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2473 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2474 int options
= linux_low_ptrace_options (proc
->attached
);
2476 linux_enable_event_reporting (lwpid
, options
);
2477 child
->must_set_ptrace_flags
= 0;
2480 /* Always update syscall_state, even if it will be filtered later. */
2481 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2483 child
->syscall_state
2484 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2485 ? TARGET_WAITKIND_SYSCALL_RETURN
2486 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2490 /* Almost all other ptrace-stops are known to be outside of system
2491 calls, with further exceptions in handle_extended_wait. */
2492 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2495 /* Be careful to not overwrite stop_pc until save_stop_reason is
2497 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2498 && linux_is_extended_waitstatus (wstat
))
2500 child
->stop_pc
= get_pc (child
);
2501 if (handle_extended_wait (&child
, wstat
))
2503 /* The event has been handled, so just return without
2509 if (linux_wstatus_maybe_breakpoint (wstat
))
2511 if (save_stop_reason (child
))
2516 child
->stop_pc
= get_pc (child
);
2518 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2519 && child
->stop_expected
)
2522 debug_printf ("Expected stop.\n");
2523 child
->stop_expected
= 0;
2525 if (thread
->last_resume_kind
== resume_stop
)
2527 /* We want to report the stop to the core. Treat the
2528 SIGSTOP as a normal event. */
2530 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2531 target_pid_to_str (ptid_of (thread
)));
2533 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2535 /* Stopping threads. We don't want this SIGSTOP to end up
2538 debug_printf ("LLW: SIGSTOP caught for %s "
2539 "while stopping threads.\n",
2540 target_pid_to_str (ptid_of (thread
)));
2545 /* This is a delayed SIGSTOP. Filter out the event. */
2547 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2548 child
->stepping
? "step" : "continue",
2549 target_pid_to_str (ptid_of (thread
)));
2551 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2556 child
->status_pending_p
= 1;
2557 child
->status_pending
= wstat
;
2561 /* Return true if THREAD is doing hardware single step. */
2564 maybe_hw_step (struct thread_info
*thread
)
2566 if (can_hardware_single_step ())
2570 /* GDBserver must insert single-step breakpoint for software
2572 gdb_assert (has_single_step_breakpoints (thread
));
2577 /* Resume LWPs that are currently stopped without any pending status
2578 to report, but are resumed from the core's perspective. */
2581 resume_stopped_resumed_lwps (thread_info
*thread
)
2583 struct lwp_info
*lp
= get_thread_lwp (thread
);
2587 && !lp
->status_pending_p
2588 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2592 if (thread
->last_resume_kind
== resume_step
)
2593 step
= maybe_hw_step (thread
);
2596 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2597 target_pid_to_str (ptid_of (thread
)),
2598 paddress (lp
->stop_pc
),
2601 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2605 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2606 match FILTER_PTID (leaving others pending). The PTIDs can be:
2607 minus_one_ptid, to specify any child; a pid PTID, specifying all
2608 lwps of a thread group; or a PTID representing a single lwp. Store
2609 the stop status through the status pointer WSTAT. OPTIONS is
2610 passed to the waitpid call. Return 0 if no event was found and
2611 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2612 was found. Return the PID of the stopped child otherwise. */
2615 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2616 int *wstatp
, int options
)
2618 struct thread_info
*event_thread
;
2619 struct lwp_info
*event_child
, *requested_child
;
2620 sigset_t block_mask
, prev_mask
;
2623 /* N.B. event_thread points to the thread_info struct that contains
2624 event_child. Keep them in sync. */
2625 event_thread
= NULL
;
2627 requested_child
= NULL
;
2629 /* Check for a lwp with a pending status. */
2631 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2633 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2635 return status_pending_p_callback (thread
, filter_ptid
);
2638 if (event_thread
!= NULL
)
2639 event_child
= get_thread_lwp (event_thread
);
2640 if (debug_threads
&& event_thread
)
2641 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2643 else if (filter_ptid
!= null_ptid
)
2645 requested_child
= find_lwp_pid (filter_ptid
);
2647 if (stopping_threads
== NOT_STOPPING_THREADS
2648 && requested_child
->status_pending_p
2649 && (requested_child
->collecting_fast_tracepoint
2650 != fast_tpoint_collect_result::not_collecting
))
2652 enqueue_one_deferred_signal (requested_child
,
2653 &requested_child
->status_pending
);
2654 requested_child
->status_pending_p
= 0;
2655 requested_child
->status_pending
= 0;
2656 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2659 if (requested_child
->suspended
2660 && requested_child
->status_pending_p
)
2662 internal_error (__FILE__
, __LINE__
,
2663 "requesting an event out of a"
2664 " suspended child?");
2667 if (requested_child
->status_pending_p
)
2669 event_child
= requested_child
;
2670 event_thread
= get_lwp_thread (event_child
);
2674 if (event_child
!= NULL
)
2677 debug_printf ("Got an event from pending child %ld (%04x)\n",
2678 lwpid_of (event_thread
), event_child
->status_pending
);
2679 *wstatp
= event_child
->status_pending
;
2680 event_child
->status_pending_p
= 0;
2681 event_child
->status_pending
= 0;
2682 current_thread
= event_thread
;
2683 return lwpid_of (event_thread
);
2686 /* But if we don't find a pending event, we'll have to wait.
2688 We only enter this loop if no process has a pending wait status.
2689 Thus any action taken in response to a wait status inside this
2690 loop is responding as soon as we detect the status, not after any
2693 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2694 all signals while here. */
2695 sigfillset (&block_mask
);
2696 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2698 /* Always pull all events out of the kernel. We'll randomly select
2699 an event LWP out of all that have events, to prevent
2701 while (event_child
== NULL
)
2705 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2708 - If the thread group leader exits while other threads in the
2709 thread group still exist, waitpid(TGID, ...) hangs. That
2710 waitpid won't return an exit status until the other threads
2711 in the group are reaped.
2713 - When a non-leader thread execs, that thread just vanishes
2714 without reporting an exit (so we'd hang if we waited for it
2715 explicitly in that case). The exec event is reported to
2718 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2721 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2722 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2728 debug_printf ("LLW: waitpid %ld received %s\n",
2729 (long) ret
, status_to_str (*wstatp
));
2732 /* Filter all events. IOW, leave all events pending. We'll
2733 randomly select an event LWP out of all that have events
2735 linux_low_filter_event (ret
, *wstatp
);
2736 /* Retry until nothing comes out of waitpid. A single
2737 SIGCHLD can indicate more than one child stopped. */
2741 /* Now that we've pulled all events out of the kernel, resume
2742 LWPs that don't have an interesting event to report. */
2743 if (stopping_threads
== NOT_STOPPING_THREADS
)
2744 for_each_thread (resume_stopped_resumed_lwps
);
2746 /* ... and find an LWP with a status to report to the core, if
2748 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2750 return status_pending_p_callback (thread
, filter_ptid
);
2753 if (event_thread
!= NULL
)
2755 event_child
= get_thread_lwp (event_thread
);
2756 *wstatp
= event_child
->status_pending
;
2757 event_child
->status_pending_p
= 0;
2758 event_child
->status_pending
= 0;
2762 /* Check for zombie thread group leaders. Those can't be reaped
2763 until all other threads in the thread group are. */
2764 check_zombie_leaders ();
2766 auto not_stopped
= [&] (thread_info
*thread
)
2768 return not_stopped_callback (thread
, wait_ptid
);
2771 /* If there are no resumed children left in the set of LWPs we
2772 want to wait for, bail. We can't just block in
2773 waitpid/sigsuspend, because lwps might have been left stopped
2774 in trace-stop state, and we'd be stuck forever waiting for
2775 their status to change (which would only happen if we resumed
2776 them). Even if WNOHANG is set, this return code is preferred
2777 over 0 (below), as it is more detailed. */
2778 if (find_thread (not_stopped
) == NULL
)
2781 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2782 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2786 /* No interesting event to report to the caller. */
2787 if ((options
& WNOHANG
))
2790 debug_printf ("WNOHANG set, no event found\n");
2792 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2796 /* Block until we get an event reported with SIGCHLD. */
2798 debug_printf ("sigsuspend'ing\n");
2800 sigsuspend (&prev_mask
);
2801 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2805 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2807 current_thread
= event_thread
;
2809 return lwpid_of (event_thread
);
2812 /* Wait for an event from child(ren) PTID. PTIDs can be:
2813 minus_one_ptid, to specify any child; a pid PTID, specifying all
2814 lwps of a thread group; or a PTID representing a single lwp. Store
2815 the stop status through the status pointer WSTAT. OPTIONS is
2816 passed to the waitpid call. Return 0 if no event was found and
2817 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2818 was found. Return the PID of the stopped child otherwise. */
2821 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2823 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2826 /* Select one LWP out of those that have events pending. */
2829 select_event_lwp (struct lwp_info
**orig_lp
)
2831 struct thread_info
*event_thread
= NULL
;
2833 /* In all-stop, give preference to the LWP that is being
2834 single-stepped. There will be at most one, and it's the LWP that
2835 the core is most interested in. If we didn't do this, then we'd
2836 have to handle pending step SIGTRAPs somehow in case the core
2837 later continues the previously-stepped thread, otherwise we'd
2838 report the pending SIGTRAP, and the core, not having stepped the
2839 thread, wouldn't understand what the trap was for, and therefore
2840 would report it to the user as a random signal. */
2843 event_thread
= find_thread ([] (thread_info
*thread
)
2845 lwp_info
*lp
= get_thread_lwp (thread
);
2847 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2848 && thread
->last_resume_kind
== resume_step
2849 && lp
->status_pending_p
);
2852 if (event_thread
!= NULL
)
2855 debug_printf ("SEL: Select single-step %s\n",
2856 target_pid_to_str (ptid_of (event_thread
)));
2859 if (event_thread
== NULL
)
2861 /* No single-stepping LWP. Select one at random, out of those
2862 which have had events. */
2864 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2866 lwp_info
*lp
= get_thread_lwp (thread
);
2868 /* Only resumed LWPs that have an event pending. */
2869 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2870 && lp
->status_pending_p
);
2874 if (event_thread
!= NULL
)
2876 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2878 /* Switch the event LWP. */
2879 *orig_lp
= event_lp
;
2883 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2887 unsuspend_all_lwps (struct lwp_info
*except
)
2889 for_each_thread ([&] (thread_info
*thread
)
2891 lwp_info
*lwp
= get_thread_lwp (thread
);
2894 lwp_suspended_decr (lwp
);
2898 static void move_out_of_jump_pad_callback (thread_info
*thread
);
2899 static bool stuck_in_jump_pad_callback (thread_info
*thread
);
2900 static bool lwp_running (thread_info
*thread
);
2901 static ptid_t
linux_wait_1 (ptid_t ptid
,
2902 struct target_waitstatus
*ourstatus
,
2903 int target_options
);
2905 /* Stabilize threads (move out of jump pads).
2907 If a thread is midway collecting a fast tracepoint, we need to
2908 finish the collection and move it out of the jump pad before
2909 reporting the signal.
2911 This avoids recursion while collecting (when a signal arrives
2912 midway, and the signal handler itself collects), which would trash
2913 the trace buffer. In case the user set a breakpoint in a signal
2914 handler, this avoids the backtrace showing the jump pad, etc..
2915 Most importantly, there are certain things we can't do safely if
2916 threads are stopped in a jump pad (or in its callee's). For
2919 - starting a new trace run. A thread still collecting the
2920 previous run, could trash the trace buffer when resumed. The trace
2921 buffer control structures would have been reset but the thread had
2922 no way to tell. The thread could even midway memcpy'ing to the
2923 buffer, which would mean that when resumed, it would clobber the
2924 trace buffer that had been set for a new run.
2926 - we can't rewrite/reuse the jump pads for new tracepoints
2927 safely. Say you do tstart while a thread is stopped midway while
2928 collecting. When the thread is later resumed, it finishes the
2929 collection, and returns to the jump pad, to execute the original
2930 instruction that was under the tracepoint jump at the time the
2931 older run had been started. If the jump pad had been rewritten
2932 since for something else in the new run, the thread would now
2933 execute the wrong / random instructions. */
2936 linux_stabilize_threads (void)
2938 thread_info
*thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2940 if (thread_stuck
!= NULL
)
2943 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2944 lwpid_of (thread_stuck
));
2948 thread_info
*saved_thread
= current_thread
;
2950 stabilizing_threads
= 1;
2953 for_each_thread (move_out_of_jump_pad_callback
);
2955 /* Loop until all are stopped out of the jump pads. */
2956 while (find_thread (lwp_running
) != NULL
)
2958 struct target_waitstatus ourstatus
;
2959 struct lwp_info
*lwp
;
2962 /* Note that we go through the full wait even loop. While
2963 moving threads out of jump pad, we need to be able to step
2964 over internal breakpoints and such. */
2965 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2967 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2969 lwp
= get_thread_lwp (current_thread
);
2972 lwp_suspended_inc (lwp
);
2974 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2975 || current_thread
->last_resume_kind
== resume_stop
)
2977 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2978 enqueue_one_deferred_signal (lwp
, &wstat
);
2983 unsuspend_all_lwps (NULL
);
2985 stabilizing_threads
= 0;
2987 current_thread
= saved_thread
;
2991 thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2993 if (thread_stuck
!= NULL
)
2994 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2995 lwpid_of (thread_stuck
));
2999 /* Convenience function that is called when the kernel reports an
3000 event that is not passed out to GDB. */
3003 ignore_event (struct target_waitstatus
*ourstatus
)
3005 /* If we got an event, there may still be others, as a single
3006 SIGCHLD can indicate more than one child stopped. This forces
3007 another target_wait call. */
3010 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3014 /* Convenience function that is called when the kernel reports an exit
3015 event. This decides whether to report the event to GDB as a
3016 process exit event, a thread exit event, or to suppress the
3020 filter_exit_event (struct lwp_info
*event_child
,
3021 struct target_waitstatus
*ourstatus
)
3023 client_state
&cs
= get_client_state ();
3024 struct thread_info
*thread
= get_lwp_thread (event_child
);
3025 ptid_t ptid
= ptid_of (thread
);
3027 if (!last_thread_of_process_p (pid_of (thread
)))
3029 if (cs
.report_thread_events
)
3030 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3032 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3034 delete_lwp (event_child
);
3039 /* Returns 1 if GDB is interested in any event_child syscalls. */
3042 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3044 struct thread_info
*thread
= get_lwp_thread (event_child
);
3045 struct process_info
*proc
= get_thread_process (thread
);
3047 return !proc
->syscalls_to_catch
.empty ();
3050 /* Returns 1 if GDB is interested in the event_child syscall.
3051 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3054 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3057 struct thread_info
*thread
= get_lwp_thread (event_child
);
3058 struct process_info
*proc
= get_thread_process (thread
);
3060 if (proc
->syscalls_to_catch
.empty ())
3063 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
3066 get_syscall_trapinfo (event_child
, &sysno
);
3068 for (int iter
: proc
->syscalls_to_catch
)
3075 /* Wait for process, returns status. */
3078 linux_wait_1 (ptid_t ptid
,
3079 struct target_waitstatus
*ourstatus
, int target_options
)
3081 client_state
&cs
= get_client_state ();
3083 struct lwp_info
*event_child
;
3086 int step_over_finished
;
3087 int bp_explains_trap
;
3088 int maybe_internal_trap
;
3097 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3100 /* Translate generic target options into linux options. */
3102 if (target_options
& TARGET_WNOHANG
)
3105 bp_explains_trap
= 0;
3108 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3110 auto status_pending_p_any
= [&] (thread_info
*thread
)
3112 return status_pending_p_callback (thread
, minus_one_ptid
);
3115 auto not_stopped
= [&] (thread_info
*thread
)
3117 return not_stopped_callback (thread
, minus_one_ptid
);
3120 /* Find a resumed LWP, if any. */
3121 if (find_thread (status_pending_p_any
) != NULL
)
3123 else if (find_thread (not_stopped
) != NULL
)
3128 if (step_over_bkpt
== null_ptid
)
3129 pid
= linux_wait_for_event (ptid
, &w
, options
);
3133 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3134 target_pid_to_str (step_over_bkpt
));
3135 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3138 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3140 gdb_assert (target_options
& TARGET_WNOHANG
);
3144 debug_printf ("linux_wait_1 ret = null_ptid, "
3145 "TARGET_WAITKIND_IGNORE\n");
3149 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3156 debug_printf ("linux_wait_1 ret = null_ptid, "
3157 "TARGET_WAITKIND_NO_RESUMED\n");
3161 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3165 event_child
= get_thread_lwp (current_thread
);
3167 /* linux_wait_for_event only returns an exit status for the last
3168 child of a process. Report it. */
3169 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3173 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3174 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3178 debug_printf ("linux_wait_1 ret = %s, exited with "
3180 target_pid_to_str (ptid_of (current_thread
)),
3187 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3188 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3192 debug_printf ("linux_wait_1 ret = %s, terminated with "
3194 target_pid_to_str (ptid_of (current_thread
)),
3200 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3201 return filter_exit_event (event_child
, ourstatus
);
3203 return ptid_of (current_thread
);
3206 /* If step-over executes a breakpoint instruction, in the case of a
3207 hardware single step it means a gdb/gdbserver breakpoint had been
3208 planted on top of a permanent breakpoint, in the case of a software
3209 single step it may just mean that gdbserver hit the reinsert breakpoint.
3210 The PC has been adjusted by save_stop_reason to point at
3211 the breakpoint address.
3212 So in the case of the hardware single step advance the PC manually
3213 past the breakpoint and in the case of software single step advance only
3214 if it's not the single_step_breakpoint we are hitting.
3215 This avoids that a program would keep trapping a permanent breakpoint
3217 if (step_over_bkpt
!= null_ptid
3218 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3219 && (event_child
->stepping
3220 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3222 int increment_pc
= 0;
3223 int breakpoint_kind
= 0;
3224 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3227 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3228 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3232 debug_printf ("step-over for %s executed software breakpoint\n",
3233 target_pid_to_str (ptid_of (current_thread
)));
3236 if (increment_pc
!= 0)
3238 struct regcache
*regcache
3239 = get_thread_regcache (current_thread
, 1);
3241 event_child
->stop_pc
+= increment_pc
;
3242 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3244 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3245 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3249 /* If this event was not handled before, and is not a SIGTRAP, we
3250 report it. SIGILL and SIGSEGV are also treated as traps in case
3251 a breakpoint is inserted at the current PC. If this target does
3252 not support internal breakpoints at all, we also report the
3253 SIGTRAP without further processing; it's of no concern to us. */
3255 = (supports_breakpoints ()
3256 && (WSTOPSIG (w
) == SIGTRAP
3257 || ((WSTOPSIG (w
) == SIGILL
3258 || WSTOPSIG (w
) == SIGSEGV
)
3259 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3261 if (maybe_internal_trap
)
3263 /* Handle anything that requires bookkeeping before deciding to
3264 report the event or continue waiting. */
3266 /* First check if we can explain the SIGTRAP with an internal
3267 breakpoint, or if we should possibly report the event to GDB.
3268 Do this before anything that may remove or insert a
3270 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3272 /* We have a SIGTRAP, possibly a step-over dance has just
3273 finished. If so, tweak the state machine accordingly,
3274 reinsert breakpoints and delete any single-step
3276 step_over_finished
= finish_step_over (event_child
);
3278 /* Now invoke the callbacks of any internal breakpoints there. */
3279 check_breakpoints (event_child
->stop_pc
);
3281 /* Handle tracepoint data collecting. This may overflow the
3282 trace buffer, and cause a tracing stop, removing
3284 trace_event
= handle_tracepoints (event_child
);
3286 if (bp_explains_trap
)
3289 debug_printf ("Hit a gdbserver breakpoint.\n");
3294 /* We have some other signal, possibly a step-over dance was in
3295 progress, and it should be cancelled too. */
3296 step_over_finished
= finish_step_over (event_child
);
3299 /* We have all the data we need. Either report the event to GDB, or
3300 resume threads and keep waiting for more. */
3302 /* If we're collecting a fast tracepoint, finish the collection and
3303 move out of the jump pad before delivering a signal. See
3304 linux_stabilize_threads. */
3307 && WSTOPSIG (w
) != SIGTRAP
3308 && supports_fast_tracepoints ()
3309 && agent_loaded_p ())
3312 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3313 "to defer or adjust it.\n",
3314 WSTOPSIG (w
), lwpid_of (current_thread
));
3316 /* Allow debugging the jump pad itself. */
3317 if (current_thread
->last_resume_kind
!= resume_step
3318 && maybe_move_out_of_jump_pad (event_child
, &w
))
3320 enqueue_one_deferred_signal (event_child
, &w
);
3323 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3324 WSTOPSIG (w
), lwpid_of (current_thread
));
3326 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3330 return ignore_event (ourstatus
);
3334 if (event_child
->collecting_fast_tracepoint
3335 != fast_tpoint_collect_result::not_collecting
)
3338 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3339 "Check if we're already there.\n",
3340 lwpid_of (current_thread
),
3341 (int) event_child
->collecting_fast_tracepoint
);
3345 event_child
->collecting_fast_tracepoint
3346 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3348 if (event_child
->collecting_fast_tracepoint
3349 != fast_tpoint_collect_result::before_insn
)
3351 /* No longer need this breakpoint. */
3352 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3355 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3356 "stopping all threads momentarily.\n");
3358 /* Other running threads could hit this breakpoint.
3359 We don't handle moribund locations like GDB does,
3360 instead we always pause all threads when removing
3361 breakpoints, so that any step-over or
3362 decr_pc_after_break adjustment is always taken
3363 care of while the breakpoint is still
3365 stop_all_lwps (1, event_child
);
3367 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3368 event_child
->exit_jump_pad_bkpt
= NULL
;
3370 unstop_all_lwps (1, event_child
);
3372 gdb_assert (event_child
->suspended
>= 0);
3376 if (event_child
->collecting_fast_tracepoint
3377 == fast_tpoint_collect_result::not_collecting
)
3380 debug_printf ("fast tracepoint finished "
3381 "collecting successfully.\n");
3383 /* We may have a deferred signal to report. */
3384 if (dequeue_one_deferred_signal (event_child
, &w
))
3387 debug_printf ("dequeued one signal.\n");
3392 debug_printf ("no deferred signals.\n");
3394 if (stabilizing_threads
)
3396 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3397 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3401 debug_printf ("linux_wait_1 ret = %s, stopped "
3402 "while stabilizing threads\n",
3403 target_pid_to_str (ptid_of (current_thread
)));
3407 return ptid_of (current_thread
);
3413 /* Check whether GDB would be interested in this event. */
3415 /* Check if GDB is interested in this syscall. */
3417 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3418 && !gdb_catch_this_syscall_p (event_child
))
3422 debug_printf ("Ignored syscall for LWP %ld.\n",
3423 lwpid_of (current_thread
));
3426 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3431 return ignore_event (ourstatus
);
3434 /* If GDB is not interested in this signal, don't stop other
3435 threads, and don't report it to GDB. Just resume the inferior
3436 right away. We do this for threading-related signals as well as
3437 any that GDB specifically requested we ignore. But never ignore
3438 SIGSTOP if we sent it ourselves, and do not ignore signals when
3439 stepping - they may require special handling to skip the signal
3440 handler. Also never ignore signals that could be caused by a
3443 && current_thread
->last_resume_kind
!= resume_step
3445 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3446 (current_process ()->priv
->thread_db
!= NULL
3447 && (WSTOPSIG (w
) == __SIGRTMIN
3448 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3451 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3452 && !(WSTOPSIG (w
) == SIGSTOP
3453 && current_thread
->last_resume_kind
== resume_stop
)
3454 && !linux_wstatus_maybe_breakpoint (w
))))
3456 siginfo_t info
, *info_p
;
3459 debug_printf ("Ignored signal %d for LWP %ld.\n",
3460 WSTOPSIG (w
), lwpid_of (current_thread
));
3462 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3463 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3468 if (step_over_finished
)
3470 /* We cancelled this thread's step-over above. We still
3471 need to unsuspend all other LWPs, and set them back
3472 running again while the signal handler runs. */
3473 unsuspend_all_lwps (event_child
);
3475 /* Enqueue the pending signal info so that proceed_all_lwps
3477 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3479 proceed_all_lwps ();
3483 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3484 WSTOPSIG (w
), info_p
);
3490 return ignore_event (ourstatus
);
3493 /* Note that all addresses are always "out of the step range" when
3494 there's no range to begin with. */
3495 in_step_range
= lwp_in_step_range (event_child
);
3497 /* If GDB wanted this thread to single step, and the thread is out
3498 of the step range, we always want to report the SIGTRAP, and let
3499 GDB handle it. Watchpoints should always be reported. So should
3500 signals we can't explain. A SIGTRAP we can't explain could be a
3501 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3502 do, we're be able to handle GDB breakpoints on top of internal
3503 breakpoints, by handling the internal breakpoint and still
3504 reporting the event to GDB. If we don't, we're out of luck, GDB
3505 won't see the breakpoint hit. If we see a single-step event but
3506 the thread should be continuing, don't pass the trap to gdb.
3507 That indicates that we had previously finished a single-step but
3508 left the single-step pending -- see
3509 complete_ongoing_step_over. */
3510 report_to_gdb
= (!maybe_internal_trap
3511 || (current_thread
->last_resume_kind
== resume_step
3513 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3515 && !bp_explains_trap
3517 && !step_over_finished
3518 && !(current_thread
->last_resume_kind
== resume_continue
3519 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3520 || (gdb_breakpoint_here (event_child
->stop_pc
)
3521 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3522 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3523 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3525 run_breakpoint_commands (event_child
->stop_pc
);
3527 /* We found no reason GDB would want us to stop. We either hit one
3528 of our own breakpoints, or finished an internal step GDB
3529 shouldn't know about. */
3534 if (bp_explains_trap
)
3535 debug_printf ("Hit a gdbserver breakpoint.\n");
3536 if (step_over_finished
)
3537 debug_printf ("Step-over finished.\n");
3539 debug_printf ("Tracepoint event.\n");
3540 if (lwp_in_step_range (event_child
))
3541 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3542 paddress (event_child
->stop_pc
),
3543 paddress (event_child
->step_range_start
),
3544 paddress (event_child
->step_range_end
));
3547 /* We're not reporting this breakpoint to GDB, so apply the
3548 decr_pc_after_break adjustment to the inferior's regcache
3551 if (the_low_target
.set_pc
!= NULL
)
3553 struct regcache
*regcache
3554 = get_thread_regcache (current_thread
, 1);
3555 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3558 if (step_over_finished
)
3560 /* If we have finished stepping over a breakpoint, we've
3561 stopped and suspended all LWPs momentarily except the
3562 stepping one. This is where we resume them all again.
3563 We're going to keep waiting, so use proceed, which
3564 handles stepping over the next breakpoint. */
3565 unsuspend_all_lwps (event_child
);
3569 /* Remove the single-step breakpoints if any. Note that
3570 there isn't single-step breakpoint if we finished stepping
3572 if (can_software_single_step ()
3573 && has_single_step_breakpoints (current_thread
))
3575 stop_all_lwps (0, event_child
);
3576 delete_single_step_breakpoints (current_thread
);
3577 unstop_all_lwps (0, event_child
);
3582 debug_printf ("proceeding all threads.\n");
3583 proceed_all_lwps ();
3588 return ignore_event (ourstatus
);
3593 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3596 = target_waitstatus_to_string (&event_child
->waitstatus
);
3598 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3599 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3601 if (current_thread
->last_resume_kind
== resume_step
)
3603 if (event_child
->step_range_start
== event_child
->step_range_end
)
3604 debug_printf ("GDB wanted to single-step, reporting event.\n");
3605 else if (!lwp_in_step_range (event_child
))
3606 debug_printf ("Out of step range, reporting event.\n");
3608 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3609 debug_printf ("Stopped by watchpoint.\n");
3610 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3611 debug_printf ("Stopped by GDB breakpoint.\n");
3613 debug_printf ("Hit a non-gdbserver trap event.\n");
3616 /* Alright, we're going to report a stop. */
3618 /* Remove single-step breakpoints. */
3619 if (can_software_single_step ())
3621 /* Remove single-step breakpoints or not. It it is true, stop all
3622 lwps, so that other threads won't hit the breakpoint in the
3624 int remove_single_step_breakpoints_p
= 0;
3628 remove_single_step_breakpoints_p
3629 = has_single_step_breakpoints (current_thread
);
3633 /* In all-stop, a stop reply cancels all previous resume
3634 requests. Delete all single-step breakpoints. */
3636 find_thread ([&] (thread_info
*thread
) {
3637 if (has_single_step_breakpoints (thread
))
3639 remove_single_step_breakpoints_p
= 1;
3647 if (remove_single_step_breakpoints_p
)
3649 /* If we remove single-step breakpoints from memory, stop all lwps,
3650 so that other threads won't hit the breakpoint in the staled
3652 stop_all_lwps (0, event_child
);
3656 gdb_assert (has_single_step_breakpoints (current_thread
));
3657 delete_single_step_breakpoints (current_thread
);
3661 for_each_thread ([] (thread_info
*thread
){
3662 if (has_single_step_breakpoints (thread
))
3663 delete_single_step_breakpoints (thread
);
3667 unstop_all_lwps (0, event_child
);
3671 if (!stabilizing_threads
)
3673 /* In all-stop, stop all threads. */
3675 stop_all_lwps (0, NULL
);
3677 if (step_over_finished
)
3681 /* If we were doing a step-over, all other threads but
3682 the stepping one had been paused in start_step_over,
3683 with their suspend counts incremented. We don't want
3684 to do a full unstop/unpause, because we're in
3685 all-stop mode (so we want threads stopped), but we
3686 still need to unsuspend the other threads, to
3687 decrement their `suspended' count back. */
3688 unsuspend_all_lwps (event_child
);
3692 /* If we just finished a step-over, then all threads had
3693 been momentarily paused. In all-stop, that's fine,
3694 we want threads stopped by now anyway. In non-stop,
3695 we need to re-resume threads that GDB wanted to be
3697 unstop_all_lwps (1, event_child
);
3701 /* If we're not waiting for a specific LWP, choose an event LWP
3702 from among those that have had events. Giving equal priority
3703 to all LWPs that have had events helps prevent
3705 if (ptid
== minus_one_ptid
)
3707 event_child
->status_pending_p
= 1;
3708 event_child
->status_pending
= w
;
3710 select_event_lwp (&event_child
);
3712 /* current_thread and event_child must stay in sync. */
3713 current_thread
= get_lwp_thread (event_child
);
3715 event_child
->status_pending_p
= 0;
3716 w
= event_child
->status_pending
;
3720 /* Stabilize threads (move out of jump pads). */
3722 stabilize_threads ();
3726 /* If we just finished a step-over, then all threads had been
3727 momentarily paused. In all-stop, that's fine, we want
3728 threads stopped by now anyway. In non-stop, we need to
3729 re-resume threads that GDB wanted to be running. */
3730 if (step_over_finished
)
3731 unstop_all_lwps (1, event_child
);
3734 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3736 /* If the reported event is an exit, fork, vfork or exec, let
3739 /* Break the unreported fork relationship chain. */
3740 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3741 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3743 event_child
->fork_relative
->fork_relative
= NULL
;
3744 event_child
->fork_relative
= NULL
;
3747 *ourstatus
= event_child
->waitstatus
;
3748 /* Clear the event lwp's waitstatus since we handled it already. */
3749 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3752 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3754 /* Now that we've selected our final event LWP, un-adjust its PC if
3755 it was a software breakpoint, and the client doesn't know we can
3756 adjust the breakpoint ourselves. */
3757 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3758 && !cs
.swbreak_feature
)
3760 int decr_pc
= the_low_target
.decr_pc_after_break
;
3764 struct regcache
*regcache
3765 = get_thread_regcache (current_thread
, 1);
3766 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3770 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3772 get_syscall_trapinfo (event_child
,
3773 &ourstatus
->value
.syscall_number
);
3774 ourstatus
->kind
= event_child
->syscall_state
;
3776 else if (current_thread
->last_resume_kind
== resume_stop
3777 && WSTOPSIG (w
) == SIGSTOP
)
3779 /* A thread that has been requested to stop by GDB with vCont;t,
3780 and it stopped cleanly, so report as SIG0. The use of
3781 SIGSTOP is an implementation detail. */
3782 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3784 else if (current_thread
->last_resume_kind
== resume_stop
3785 && WSTOPSIG (w
) != SIGSTOP
)
3787 /* A thread that has been requested to stop by GDB with vCont;t,
3788 but, it stopped for other reasons. */
3789 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3791 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3793 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3796 gdb_assert (step_over_bkpt
== null_ptid
);
3800 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3801 target_pid_to_str (ptid_of (current_thread
)),
3802 ourstatus
->kind
, ourstatus
->value
.sig
);
3806 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3807 return filter_exit_event (event_child
, ourstatus
);
3809 return ptid_of (current_thread
);
3812 /* Get rid of any pending event in the pipe. */
3814 async_file_flush (void)
3820 ret
= read (linux_event_pipe
[0], &buf
, 1);
3821 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3824 /* Put something in the pipe, so the event loop wakes up. */
3826 async_file_mark (void)
3830 async_file_flush ();
3833 ret
= write (linux_event_pipe
[1], "+", 1);
3834 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3836 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3837 be awakened anyway. */
3841 linux_wait (ptid_t ptid
,
3842 struct target_waitstatus
*ourstatus
, int target_options
)
3846 /* Flush the async file first. */
3847 if (target_is_async_p ())
3848 async_file_flush ();
3852 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3854 while ((target_options
& TARGET_WNOHANG
) == 0
3855 && event_ptid
== null_ptid
3856 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3858 /* If at least one stop was reported, there may be more. A single
3859 SIGCHLD can signal more than one child stop. */
3860 if (target_is_async_p ()
3861 && (target_options
& TARGET_WNOHANG
) != 0
3862 && event_ptid
!= null_ptid
)
3868 /* Send a signal to an LWP. */
3871 kill_lwp (unsigned long lwpid
, int signo
)
3876 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3877 if (errno
== ENOSYS
)
3879 /* If tkill fails, then we are not using nptl threads, a
3880 configuration we no longer support. */
3881 perror_with_name (("tkill"));
3887 linux_stop_lwp (struct lwp_info
*lwp
)
3893 send_sigstop (struct lwp_info
*lwp
)
3897 pid
= lwpid_of (get_lwp_thread (lwp
));
3899 /* If we already have a pending stop signal for this process, don't
3901 if (lwp
->stop_expected
)
3904 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3910 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3912 lwp
->stop_expected
= 1;
3913 kill_lwp (pid
, SIGSTOP
);
3917 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3919 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3921 /* Ignore EXCEPT. */
3931 /* Increment the suspend count of an LWP, and stop it, if not stopped
3934 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3936 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3938 /* Ignore EXCEPT. */
3942 lwp_suspended_inc (lwp
);
3944 send_sigstop (thread
, except
);
3948 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3950 /* Store the exit status for later. */
3951 lwp
->status_pending_p
= 1;
3952 lwp
->status_pending
= wstat
;
3954 /* Store in waitstatus as well, as there's nothing else to process
3956 if (WIFEXITED (wstat
))
3958 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3959 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3961 else if (WIFSIGNALED (wstat
))
3963 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3964 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3967 /* Prevent trying to stop it. */
3970 /* No further stops are expected from a dead lwp. */
3971 lwp
->stop_expected
= 0;
3974 /* Return true if LWP has exited already, and has a pending exit event
3975 to report to GDB. */
3978 lwp_is_marked_dead (struct lwp_info
*lwp
)
3980 return (lwp
->status_pending_p
3981 && (WIFEXITED (lwp
->status_pending
)
3982 || WIFSIGNALED (lwp
->status_pending
)));
3985 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3988 wait_for_sigstop (void)
3990 struct thread_info
*saved_thread
;
3995 saved_thread
= current_thread
;
3996 if (saved_thread
!= NULL
)
3997 saved_tid
= saved_thread
->id
;
3999 saved_tid
= null_ptid
; /* avoid bogus unused warning */
4002 debug_printf ("wait_for_sigstop: pulling events\n");
4004 /* Passing NULL_PTID as filter indicates we want all events to be
4005 left pending. Eventually this returns when there are no
4006 unwaited-for children left. */
4007 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4009 gdb_assert (ret
== -1);
4011 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
4012 current_thread
= saved_thread
;
4016 debug_printf ("Previously current thread died.\n");
4018 /* We can't change the current inferior behind GDB's back,
4019 otherwise, a subsequent command may apply to the wrong
4021 current_thread
= NULL
;
4025 /* Returns true if THREAD is stopped in a jump pad, and we can't
4026 move it out, because we need to report the stop event to GDB. For
4027 example, if the user puts a breakpoint in the jump pad, it's
4028 because she wants to debug it. */
4031 stuck_in_jump_pad_callback (thread_info
*thread
)
4033 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4035 if (lwp
->suspended
!= 0)
4037 internal_error (__FILE__
, __LINE__
,
4038 "LWP %ld is suspended, suspended=%d\n",
4039 lwpid_of (thread
), lwp
->suspended
);
4041 gdb_assert (lwp
->stopped
);
4043 /* Allow debugging the jump pad, gdb_collect, etc.. */
4044 return (supports_fast_tracepoints ()
4045 && agent_loaded_p ()
4046 && (gdb_breakpoint_here (lwp
->stop_pc
)
4047 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
4048 || thread
->last_resume_kind
== resume_step
)
4049 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
4050 != fast_tpoint_collect_result::not_collecting
));
4054 move_out_of_jump_pad_callback (thread_info
*thread
)
4056 struct thread_info
*saved_thread
;
4057 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4060 if (lwp
->suspended
!= 0)
4062 internal_error (__FILE__
, __LINE__
,
4063 "LWP %ld is suspended, suspended=%d\n",
4064 lwpid_of (thread
), lwp
->suspended
);
4066 gdb_assert (lwp
->stopped
);
4068 /* For gdb_breakpoint_here. */
4069 saved_thread
= current_thread
;
4070 current_thread
= thread
;
4072 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
4074 /* Allow debugging the jump pad, gdb_collect, etc. */
4075 if (!gdb_breakpoint_here (lwp
->stop_pc
)
4076 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4077 && thread
->last_resume_kind
!= resume_step
4078 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4081 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4086 lwp
->status_pending_p
= 0;
4087 enqueue_one_deferred_signal (lwp
, wstat
);
4090 debug_printf ("Signal %d for LWP %ld deferred "
4092 WSTOPSIG (*wstat
), lwpid_of (thread
));
4095 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4098 lwp_suspended_inc (lwp
);
4100 current_thread
= saved_thread
;
4104 lwp_running (thread_info
*thread
)
4106 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4108 if (lwp_is_marked_dead (lwp
))
4111 return !lwp
->stopped
;
4114 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4115 If SUSPEND, then also increase the suspend count of every LWP,
4119 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4121 /* Should not be called recursively. */
4122 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4127 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4128 suspend
? "stop-and-suspend" : "stop",
4130 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4134 stopping_threads
= (suspend
4135 ? STOPPING_AND_SUSPENDING_THREADS
4136 : STOPPING_THREADS
);
4139 for_each_thread ([&] (thread_info
*thread
)
4141 suspend_and_send_sigstop (thread
, except
);
4144 for_each_thread ([&] (thread_info
*thread
)
4146 send_sigstop (thread
, except
);
4149 wait_for_sigstop ();
4150 stopping_threads
= NOT_STOPPING_THREADS
;
4154 debug_printf ("stop_all_lwps done, setting stopping_threads "
4155 "back to !stopping\n");
4160 /* Enqueue one signal in the chain of signals which need to be
4161 delivered to this process on next resume. */
4164 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4166 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4168 p_sig
->prev
= lwp
->pending_signals
;
4169 p_sig
->signal
= signal
;
4171 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4173 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4174 lwp
->pending_signals
= p_sig
;
4177 /* Install breakpoints for software single stepping. */
4180 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4182 struct thread_info
*thread
= get_lwp_thread (lwp
);
4183 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4185 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4187 current_thread
= thread
;
4188 std::vector
<CORE_ADDR
> next_pcs
= the_low_target
.get_next_pcs (regcache
);
4190 for (CORE_ADDR pc
: next_pcs
)
4191 set_single_step_breakpoint (pc
, current_ptid
);
4194 /* Single step via hardware or software single step.
4195 Return 1 if hardware single stepping, 0 if software single stepping
4196 or can't single step. */
4199 single_step (struct lwp_info
* lwp
)
4203 if (can_hardware_single_step ())
4207 else if (can_software_single_step ())
4209 install_software_single_step_breakpoints (lwp
);
4215 debug_printf ("stepping is not implemented on this target");
4221 /* The signal can be delivered to the inferior if we are not trying to
4222 finish a fast tracepoint collect. Since signal can be delivered in
4223 the step-over, the program may go to signal handler and trap again
4224 after return from the signal handler. We can live with the spurious
4228 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4230 return (lwp
->collecting_fast_tracepoint
4231 == fast_tpoint_collect_result::not_collecting
);
4234 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4235 SIGNAL is nonzero, give it that signal. */
4238 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4239 int step
, int signal
, siginfo_t
*info
)
4241 struct thread_info
*thread
= get_lwp_thread (lwp
);
4242 struct thread_info
*saved_thread
;
4244 struct process_info
*proc
= get_thread_process (thread
);
4246 /* Note that target description may not be initialised
4247 (proc->tdesc == NULL) at this point because the program hasn't
4248 stopped at the first instruction yet. It means GDBserver skips
4249 the extra traps from the wrapper program (see option --wrapper).
4250 Code in this function that requires register access should be
4251 guarded by proc->tdesc == NULL or something else. */
4253 if (lwp
->stopped
== 0)
4256 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4258 fast_tpoint_collect_result fast_tp_collecting
4259 = lwp
->collecting_fast_tracepoint
;
4261 gdb_assert (!stabilizing_threads
4262 || (fast_tp_collecting
4263 != fast_tpoint_collect_result::not_collecting
));
4265 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4266 user used the "jump" command, or "set $pc = foo"). */
4267 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4269 /* Collecting 'while-stepping' actions doesn't make sense
4271 release_while_stepping_state_list (thread
);
4274 /* If we have pending signals or status, and a new signal, enqueue the
4275 signal. Also enqueue the signal if it can't be delivered to the
4276 inferior right now. */
4278 && (lwp
->status_pending_p
4279 || lwp
->pending_signals
!= NULL
4280 || !lwp_signal_can_be_delivered (lwp
)))
4282 enqueue_pending_signal (lwp
, signal
, info
);
4284 /* Postpone any pending signal. It was enqueued above. */
4288 if (lwp
->status_pending_p
)
4291 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4292 " has pending status\n",
4293 lwpid_of (thread
), step
? "step" : "continue",
4294 lwp
->stop_expected
? "expected" : "not expected");
4298 saved_thread
= current_thread
;
4299 current_thread
= thread
;
4301 /* This bit needs some thinking about. If we get a signal that
4302 we must report while a single-step reinsert is still pending,
4303 we often end up resuming the thread. It might be better to
4304 (ew) allow a stack of pending events; then we could be sure that
4305 the reinsert happened right away and not lose any signals.
4307 Making this stack would also shrink the window in which breakpoints are
4308 uninserted (see comment in linux_wait_for_lwp) but not enough for
4309 complete correctness, so it won't solve that problem. It may be
4310 worthwhile just to solve this one, however. */
4311 if (lwp
->bp_reinsert
!= 0)
4314 debug_printf (" pending reinsert at 0x%s\n",
4315 paddress (lwp
->bp_reinsert
));
4317 if (can_hardware_single_step ())
4319 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4322 warning ("BAD - reinserting but not stepping.");
4324 warning ("BAD - reinserting and suspended(%d).",
4329 step
= maybe_hw_step (thread
);
4332 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4335 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4336 " (exit-jump-pad-bkpt)\n",
4339 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4342 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4343 " single-stepping\n",
4346 if (can_hardware_single_step ())
4350 internal_error (__FILE__
, __LINE__
,
4351 "moving out of jump pad single-stepping"
4352 " not implemented on this target");
4356 /* If we have while-stepping actions in this thread set it stepping.
4357 If we have a signal to deliver, it may or may not be set to
4358 SIG_IGN, we don't know. Assume so, and allow collecting
4359 while-stepping into a signal handler. A possible smart thing to
4360 do would be to set an internal breakpoint at the signal return
4361 address, continue, and carry on catching this while-stepping
4362 action only when that breakpoint is hit. A future
4364 if (thread
->while_stepping
!= NULL
)
4367 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4370 step
= single_step (lwp
);
4373 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4375 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4377 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4381 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4382 (long) lwp
->stop_pc
);
4386 /* If we have pending signals, consume one if it can be delivered to
4388 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4390 struct pending_signals
**p_sig
;
4392 p_sig
= &lwp
->pending_signals
;
4393 while ((*p_sig
)->prev
!= NULL
)
4394 p_sig
= &(*p_sig
)->prev
;
4396 signal
= (*p_sig
)->signal
;
4397 if ((*p_sig
)->info
.si_signo
!= 0)
4398 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4406 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4407 lwpid_of (thread
), step
? "step" : "continue", signal
,
4408 lwp
->stop_expected
? "expected" : "not expected");
4410 if (the_low_target
.prepare_to_resume
!= NULL
)
4411 the_low_target
.prepare_to_resume (lwp
);
4413 regcache_invalidate_thread (thread
);
4415 lwp
->stepping
= step
;
4417 ptrace_request
= PTRACE_SINGLESTEP
;
4418 else if (gdb_catching_syscalls_p (lwp
))
4419 ptrace_request
= PTRACE_SYSCALL
;
4421 ptrace_request
= PTRACE_CONT
;
4422 ptrace (ptrace_request
,
4424 (PTRACE_TYPE_ARG3
) 0,
4425 /* Coerce to a uintptr_t first to avoid potential gcc warning
4426 of coercing an 8 byte integer to a 4 byte pointer. */
4427 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4429 current_thread
= saved_thread
;
4431 perror_with_name ("resuming thread");
4433 /* Successfully resumed. Clear state that no longer makes sense,
4434 and mark the LWP as running. Must not do this before resuming
4435 otherwise if that fails other code will be confused. E.g., we'd
4436 later try to stop the LWP and hang forever waiting for a stop
4437 status. Note that we must not throw after this is cleared,
4438 otherwise handle_zombie_lwp_error would get confused. */
4440 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4443 /* Called when we try to resume a stopped LWP and that errors out. If
4444 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4445 or about to become), discard the error, clear any pending status
4446 the LWP may have, and return true (we'll collect the exit status
4447 soon enough). Otherwise, return false. */
4450 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4452 struct thread_info
*thread
= get_lwp_thread (lp
);
4454 /* If we get an error after resuming the LWP successfully, we'd
4455 confuse !T state for the LWP being gone. */
4456 gdb_assert (lp
->stopped
);
4458 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4459 because even if ptrace failed with ESRCH, the tracee may be "not
4460 yet fully dead", but already refusing ptrace requests. In that
4461 case the tracee has 'R (Running)' state for a little bit
4462 (observed in Linux 3.18). See also the note on ESRCH in the
4463 ptrace(2) man page. Instead, check whether the LWP has any state
4464 other than ptrace-stopped. */
4466 /* Don't assume anything if /proc/PID/status can't be read. */
4467 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4469 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4470 lp
->status_pending_p
= 0;
4476 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4477 disappears while we try to resume it. */
4480 linux_resume_one_lwp (struct lwp_info
*lwp
,
4481 int step
, int signal
, siginfo_t
*info
)
4485 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4487 catch (const gdb_exception_error
&ex
)
4489 if (!check_ptrace_stopped_lwp_gone (lwp
))
4494 /* This function is called once per thread via for_each_thread.
4495 We look up which resume request applies to THREAD and mark it with a
4496 pointer to the appropriate resume request.
4498 This algorithm is O(threads * resume elements), but resume elements
4499 is small (and will remain small at least until GDB supports thread
4503 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4505 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4507 for (int ndx
= 0; ndx
< n
; ndx
++)
4509 ptid_t ptid
= resume
[ndx
].thread
;
4510 if (ptid
== minus_one_ptid
4511 || ptid
== thread
->id
4512 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4514 || (ptid
.pid () == pid_of (thread
)
4516 || ptid
.lwp () == -1)))
4518 if (resume
[ndx
].kind
== resume_stop
4519 && thread
->last_resume_kind
== resume_stop
)
4522 debug_printf ("already %s LWP %ld at GDB's request\n",
4523 (thread
->last_status
.kind
4524 == TARGET_WAITKIND_STOPPED
)
4532 /* Ignore (wildcard) resume requests for already-resumed
4534 if (resume
[ndx
].kind
!= resume_stop
4535 && thread
->last_resume_kind
!= resume_stop
)
4538 debug_printf ("already %s LWP %ld at GDB's request\n",
4539 (thread
->last_resume_kind
4547 /* Don't let wildcard resumes resume fork children that GDB
4548 does not yet know are new fork children. */
4549 if (lwp
->fork_relative
!= NULL
)
4551 struct lwp_info
*rel
= lwp
->fork_relative
;
4553 if (rel
->status_pending_p
4554 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4555 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4558 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4564 /* If the thread has a pending event that has already been
4565 reported to GDBserver core, but GDB has not pulled the
4566 event out of the vStopped queue yet, likewise, ignore the
4567 (wildcard) resume request. */
4568 if (in_queued_stop_replies (thread
->id
))
4571 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4576 lwp
->resume
= &resume
[ndx
];
4577 thread
->last_resume_kind
= lwp
->resume
->kind
;
4579 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4580 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4582 /* If we had a deferred signal to report, dequeue one now.
4583 This can happen if LWP gets more than one signal while
4584 trying to get out of a jump pad. */
4586 && !lwp
->status_pending_p
4587 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4589 lwp
->status_pending_p
= 1;
4592 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4593 "leaving status pending.\n",
4594 WSTOPSIG (lwp
->status_pending
),
4602 /* No resume action for this thread. */
4606 /* find_thread callback for linux_resume. Return true if this lwp has an
4607 interesting status pending. */
4610 resume_status_pending_p (thread_info
*thread
)
4612 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4614 /* LWPs which will not be resumed are not interesting, because
4615 we might not wait for them next time through linux_wait. */
4616 if (lwp
->resume
== NULL
)
4619 return thread_still_has_status_pending_p (thread
);
4622 /* Return 1 if this lwp that GDB wants running is stopped at an
4623 internal breakpoint that we need to step over. It assumes that any
4624 required STOP_PC adjustment has already been propagated to the
4625 inferior's regcache. */
4628 need_step_over_p (thread_info
*thread
)
4630 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4631 struct thread_info
*saved_thread
;
4633 struct process_info
*proc
= get_thread_process (thread
);
4635 /* GDBserver is skipping the extra traps from the wrapper program,
4636 don't have to do step over. */
4637 if (proc
->tdesc
== NULL
)
4640 /* LWPs which will not be resumed are not interesting, because we
4641 might not wait for them next time through linux_wait. */
4646 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4651 if (thread
->last_resume_kind
== resume_stop
)
4654 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4660 gdb_assert (lwp
->suspended
>= 0);
4665 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4670 if (lwp
->status_pending_p
)
4673 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4679 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4683 /* If the PC has changed since we stopped, then don't do anything,
4684 and let the breakpoint/tracepoint be hit. This happens if, for
4685 instance, GDB handled the decr_pc_after_break subtraction itself,
4686 GDB is OOL stepping this thread, or the user has issued a "jump"
4687 command, or poked thread's registers herself. */
4688 if (pc
!= lwp
->stop_pc
)
4691 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4692 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4694 paddress (lwp
->stop_pc
), paddress (pc
));
4698 /* On software single step target, resume the inferior with signal
4699 rather than stepping over. */
4700 if (can_software_single_step ()
4701 && lwp
->pending_signals
!= NULL
4702 && lwp_signal_can_be_delivered (lwp
))
4705 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4712 saved_thread
= current_thread
;
4713 current_thread
= thread
;
4715 /* We can only step over breakpoints we know about. */
4716 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4718 /* Don't step over a breakpoint that GDB expects to hit
4719 though. If the condition is being evaluated on the target's side
4720 and it evaluate to false, step over this breakpoint as well. */
4721 if (gdb_breakpoint_here (pc
)
4722 && gdb_condition_true_at_breakpoint (pc
)
4723 && gdb_no_commands_at_breakpoint (pc
))
4726 debug_printf ("Need step over [LWP %ld]? yes, but found"
4727 " GDB breakpoint at 0x%s; skipping step over\n",
4728 lwpid_of (thread
), paddress (pc
));
4730 current_thread
= saved_thread
;
4736 debug_printf ("Need step over [LWP %ld]? yes, "
4737 "found breakpoint at 0x%s\n",
4738 lwpid_of (thread
), paddress (pc
));
4740 /* We've found an lwp that needs stepping over --- return 1 so
4741 that find_thread stops looking. */
4742 current_thread
= saved_thread
;
4748 current_thread
= saved_thread
;
4751 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4753 lwpid_of (thread
), paddress (pc
));
4758 /* Start a step-over operation on LWP. When LWP stopped at a
4759 breakpoint, to make progress, we need to remove the breakpoint out
4760 of the way. If we let other threads run while we do that, they may
4761 pass by the breakpoint location and miss hitting it. To avoid
4762 that, a step-over momentarily stops all threads while LWP is
4763 single-stepped by either hardware or software while the breakpoint
4764 is temporarily uninserted from the inferior. When the single-step
4765 finishes, we reinsert the breakpoint, and let all threads that are
4766 supposed to be running, run again. */
4769 start_step_over (struct lwp_info
*lwp
)
4771 struct thread_info
*thread
= get_lwp_thread (lwp
);
4772 struct thread_info
*saved_thread
;
4777 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4780 stop_all_lwps (1, lwp
);
4782 if (lwp
->suspended
!= 0)
4784 internal_error (__FILE__
, __LINE__
,
4785 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4790 debug_printf ("Done stopping all threads for step-over.\n");
4792 /* Note, we should always reach here with an already adjusted PC,
4793 either by GDB (if we're resuming due to GDB's request), or by our
4794 caller, if we just finished handling an internal breakpoint GDB
4795 shouldn't care about. */
4798 saved_thread
= current_thread
;
4799 current_thread
= thread
;
4801 lwp
->bp_reinsert
= pc
;
4802 uninsert_breakpoints_at (pc
);
4803 uninsert_fast_tracepoint_jumps_at (pc
);
4805 step
= single_step (lwp
);
4807 current_thread
= saved_thread
;
4809 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4811 /* Require next event from this LWP. */
4812 step_over_bkpt
= thread
->id
;
4816 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4817 start_step_over, if still there, and delete any single-step
4818 breakpoints we've set, on non hardware single-step targets. */
4821 finish_step_over (struct lwp_info
*lwp
)
4823 if (lwp
->bp_reinsert
!= 0)
4825 struct thread_info
*saved_thread
= current_thread
;
4828 debug_printf ("Finished step over.\n");
4830 current_thread
= get_lwp_thread (lwp
);
4832 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4833 may be no breakpoint to reinsert there by now. */
4834 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4835 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4837 lwp
->bp_reinsert
= 0;
4839 /* Delete any single-step breakpoints. No longer needed. We
4840 don't have to worry about other threads hitting this trap,
4841 and later not being able to explain it, because we were
4842 stepping over a breakpoint, and we hold all threads but
4843 LWP stopped while doing that. */
4844 if (!can_hardware_single_step ())
4846 gdb_assert (has_single_step_breakpoints (current_thread
));
4847 delete_single_step_breakpoints (current_thread
);
4850 step_over_bkpt
= null_ptid
;
4851 current_thread
= saved_thread
;
4858 /* If there's a step over in progress, wait until all threads stop
4859 (that is, until the stepping thread finishes its step), and
4860 unsuspend all lwps. The stepping thread ends with its status
4861 pending, which is processed later when we get back to processing
4865 complete_ongoing_step_over (void)
4867 if (step_over_bkpt
!= null_ptid
)
4869 struct lwp_info
*lwp
;
4874 debug_printf ("detach: step over in progress, finish it first\n");
4876 /* Passing NULL_PTID as filter indicates we want all events to
4877 be left pending. Eventually this returns when there are no
4878 unwaited-for children left. */
4879 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4881 gdb_assert (ret
== -1);
4883 lwp
= find_lwp_pid (step_over_bkpt
);
4885 finish_step_over (lwp
);
4886 step_over_bkpt
= null_ptid
;
4887 unsuspend_all_lwps (lwp
);
4891 /* This function is called once per thread. We check the thread's resume
4892 request, which will tell us whether to resume, step, or leave the thread
4893 stopped; and what signal, if any, it should be sent.
4895 For threads which we aren't explicitly told otherwise, we preserve
4896 the stepping flag; this is used for stepping over gdbserver-placed
4899 If pending_flags was set in any thread, we queue any needed
4900 signals, since we won't actually resume. We already have a pending
4901 event to report, so we don't need to preserve any step requests;
4902 they should be re-issued if necessary. */
4905 linux_resume_one_thread (thread_info
*thread
, bool leave_all_stopped
)
4907 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4910 if (lwp
->resume
== NULL
)
4913 if (lwp
->resume
->kind
== resume_stop
)
4916 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4921 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4923 /* Stop the thread, and wait for the event asynchronously,
4924 through the event loop. */
4930 debug_printf ("already stopped LWP %ld\n",
4933 /* The LWP may have been stopped in an internal event that
4934 was not meant to be notified back to GDB (e.g., gdbserver
4935 breakpoint), so we should be reporting a stop event in
4938 /* If the thread already has a pending SIGSTOP, this is a
4939 no-op. Otherwise, something later will presumably resume
4940 the thread and this will cause it to cancel any pending
4941 operation, due to last_resume_kind == resume_stop. If
4942 the thread already has a pending status to report, we
4943 will still report it the next time we wait - see
4944 status_pending_p_callback. */
4946 /* If we already have a pending signal to report, then
4947 there's no need to queue a SIGSTOP, as this means we're
4948 midway through moving the LWP out of the jumppad, and we
4949 will report the pending signal as soon as that is
4951 if (lwp
->pending_signals_to_report
== NULL
)
4955 /* For stop requests, we're done. */
4957 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4961 /* If this thread which is about to be resumed has a pending status,
4962 then don't resume it - we can just report the pending status.
4963 Likewise if it is suspended, because e.g., another thread is
4964 stepping past a breakpoint. Make sure to queue any signals that
4965 would otherwise be sent. In all-stop mode, we do this decision
4966 based on if *any* thread has a pending status. If there's a
4967 thread that needs the step-over-breakpoint dance, then don't
4968 resume any other thread but that particular one. */
4969 leave_pending
= (lwp
->suspended
4970 || lwp
->status_pending_p
4971 || leave_all_stopped
);
4973 /* If we have a new signal, enqueue the signal. */
4974 if (lwp
->resume
->sig
!= 0)
4976 siginfo_t info
, *info_p
;
4978 /* If this is the same signal we were previously stopped by,
4979 make sure to queue its siginfo. */
4980 if (WIFSTOPPED (lwp
->last_status
)
4981 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4982 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4983 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4988 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4994 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4996 proceed_one_lwp (thread
, NULL
);
5001 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
5004 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
5009 linux_resume (struct thread_resume
*resume_info
, size_t n
)
5011 struct thread_info
*need_step_over
= NULL
;
5016 debug_printf ("linux_resume:\n");
5019 for_each_thread ([&] (thread_info
*thread
)
5021 linux_set_resume_request (thread
, resume_info
, n
);
5024 /* If there is a thread which would otherwise be resumed, which has
5025 a pending status, then don't resume any threads - we can just
5026 report the pending status. Make sure to queue any signals that
5027 would otherwise be sent. In non-stop mode, we'll apply this
5028 logic to each thread individually. We consume all pending events
5029 before considering to start a step-over (in all-stop). */
5030 bool any_pending
= false;
5032 any_pending
= find_thread (resume_status_pending_p
) != NULL
;
5034 /* If there is a thread which would otherwise be resumed, which is
5035 stopped at a breakpoint that needs stepping over, then don't
5036 resume any threads - have it step over the breakpoint with all
5037 other threads stopped, then resume all threads again. Make sure
5038 to queue any signals that would otherwise be delivered or
5040 if (!any_pending
&& supports_breakpoints ())
5041 need_step_over
= find_thread (need_step_over_p
);
5043 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
5047 if (need_step_over
!= NULL
)
5048 debug_printf ("Not resuming all, need step over\n");
5049 else if (any_pending
)
5050 debug_printf ("Not resuming, all-stop and found "
5051 "an LWP with pending status\n");
5053 debug_printf ("Resuming, no pending status or step over needed\n");
5056 /* Even if we're leaving threads stopped, queue all signals we'd
5057 otherwise deliver. */
5058 for_each_thread ([&] (thread_info
*thread
)
5060 linux_resume_one_thread (thread
, leave_all_stopped
);
5064 start_step_over (get_thread_lwp (need_step_over
));
5068 debug_printf ("linux_resume done\n");
5072 /* We may have events that were pending that can/should be sent to
5073 the client now. Trigger a linux_wait call. */
5074 if (target_is_async_p ())
5078 /* This function is called once per thread. We check the thread's
5079 last resume request, which will tell us whether to resume, step, or
5080 leave the thread stopped. Any signal the client requested to be
5081 delivered has already been enqueued at this point.
5083 If any thread that GDB wants running is stopped at an internal
5084 breakpoint that needs stepping over, we start a step-over operation
5085 on that particular thread, and leave all others stopped. */
5088 proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5090 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5097 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5102 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5106 if (thread
->last_resume_kind
== resume_stop
5107 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5110 debug_printf (" client wants LWP to remain %ld stopped\n",
5115 if (lwp
->status_pending_p
)
5118 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5123 gdb_assert (lwp
->suspended
>= 0);
5128 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5132 if (thread
->last_resume_kind
== resume_stop
5133 && lwp
->pending_signals_to_report
== NULL
5134 && (lwp
->collecting_fast_tracepoint
5135 == fast_tpoint_collect_result::not_collecting
))
5137 /* We haven't reported this LWP as stopped yet (otherwise, the
5138 last_status.kind check above would catch it, and we wouldn't
5139 reach here. This LWP may have been momentarily paused by a
5140 stop_all_lwps call while handling for example, another LWP's
5141 step-over. In that case, the pending expected SIGSTOP signal
5142 that was queued at vCont;t handling time will have already
5143 been consumed by wait_for_sigstop, and so we need to requeue
5144 another one here. Note that if the LWP already has a SIGSTOP
5145 pending, this is a no-op. */
5148 debug_printf ("Client wants LWP %ld to stop. "
5149 "Making sure it has a SIGSTOP pending\n",
5155 if (thread
->last_resume_kind
== resume_step
)
5158 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5161 /* If resume_step is requested by GDB, install single-step
5162 breakpoints when the thread is about to be actually resumed if
5163 the single-step breakpoints weren't removed. */
5164 if (can_software_single_step ()
5165 && !has_single_step_breakpoints (thread
))
5166 install_software_single_step_breakpoints (lwp
);
5168 step
= maybe_hw_step (thread
);
5170 else if (lwp
->bp_reinsert
!= 0)
5173 debug_printf (" stepping LWP %ld, reinsert set\n",
5176 step
= maybe_hw_step (thread
);
5181 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5185 unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5187 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5192 lwp_suspended_decr (lwp
);
5194 proceed_one_lwp (thread
, except
);
5197 /* When we finish a step-over, set threads running again. If there's
5198 another thread that may need a step-over, now's the time to start
5199 it. Eventually, we'll move all threads past their breakpoints. */
5202 proceed_all_lwps (void)
5204 struct thread_info
*need_step_over
;
5206 /* If there is a thread which would otherwise be resumed, which is
5207 stopped at a breakpoint that needs stepping over, then don't
5208 resume any threads - have it step over the breakpoint with all
5209 other threads stopped, then resume all threads again. */
5211 if (supports_breakpoints ())
5213 need_step_over
= find_thread (need_step_over_p
);
5215 if (need_step_over
!= NULL
)
5218 debug_printf ("proceed_all_lwps: found "
5219 "thread %ld needing a step-over\n",
5220 lwpid_of (need_step_over
));
5222 start_step_over (get_thread_lwp (need_step_over
));
5228 debug_printf ("Proceeding, no step-over needed\n");
5230 for_each_thread ([] (thread_info
*thread
)
5232 proceed_one_lwp (thread
, NULL
);
5236 /* Stopped LWPs that the client wanted to be running, that don't have
5237 pending statuses, are set to run again, except for EXCEPT, if not
5238 NULL. This undoes a stop_all_lwps call. */
5241 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5247 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5248 lwpid_of (get_lwp_thread (except
)));
5250 debug_printf ("unstopping all lwps\n");
5254 for_each_thread ([&] (thread_info
*thread
)
5256 unsuspend_and_proceed_one_lwp (thread
, except
);
5259 for_each_thread ([&] (thread_info
*thread
)
5261 proceed_one_lwp (thread
, except
);
5266 debug_printf ("unstop_all_lwps done\n");
5272 #ifdef HAVE_LINUX_REGSETS
5274 #define use_linux_regsets 1
5276 /* Returns true if REGSET has been disabled. */
5279 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5281 return (info
->disabled_regsets
!= NULL
5282 && info
->disabled_regsets
[regset
- info
->regsets
]);
5285 /* Disable REGSET. */
5288 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5292 dr_offset
= regset
- info
->regsets
;
5293 if (info
->disabled_regsets
== NULL
)
5294 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5295 info
->disabled_regsets
[dr_offset
] = 1;
5299 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5300 struct regcache
*regcache
)
5302 struct regset_info
*regset
;
5303 int saw_general_regs
= 0;
5307 pid
= lwpid_of (current_thread
);
5308 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5313 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5316 buf
= xmalloc (regset
->size
);
5318 nt_type
= regset
->nt_type
;
5322 iov
.iov_len
= regset
->size
;
5323 data
= (void *) &iov
;
5329 res
= ptrace (regset
->get_request
, pid
,
5330 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5332 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5337 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5339 /* If we get EIO on a regset, or an EINVAL and the regset is
5340 optional, do not try it again for this process mode. */
5341 disable_regset (regsets_info
, regset
);
5343 else if (errno
== ENODATA
)
5345 /* ENODATA may be returned if the regset is currently
5346 not "active". This can happen in normal operation,
5347 so suppress the warning in this case. */
5349 else if (errno
== ESRCH
)
5351 /* At this point, ESRCH should mean the process is
5352 already gone, in which case we simply ignore attempts
5353 to read its registers. */
5358 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5365 if (regset
->type
== GENERAL_REGS
)
5366 saw_general_regs
= 1;
5367 regset
->store_function (regcache
, buf
);
5371 if (saw_general_regs
)
5378 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5379 struct regcache
*regcache
)
5381 struct regset_info
*regset
;
5382 int saw_general_regs
= 0;
5386 pid
= lwpid_of (current_thread
);
5387 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5392 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5393 || regset
->fill_function
== NULL
)
5396 buf
= xmalloc (regset
->size
);
5398 /* First fill the buffer with the current register set contents,
5399 in case there are any items in the kernel's regset that are
5400 not in gdbserver's regcache. */
5402 nt_type
= regset
->nt_type
;
5406 iov
.iov_len
= regset
->size
;
5407 data
= (void *) &iov
;
5413 res
= ptrace (regset
->get_request
, pid
,
5414 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5416 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5421 /* Then overlay our cached registers on that. */
5422 regset
->fill_function (regcache
, buf
);
5424 /* Only now do we write the register set. */
5426 res
= ptrace (regset
->set_request
, pid
,
5427 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5429 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5436 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5438 /* If we get EIO on a regset, or an EINVAL and the regset is
5439 optional, do not try it again for this process mode. */
5440 disable_regset (regsets_info
, regset
);
5442 else if (errno
== ESRCH
)
5444 /* At this point, ESRCH should mean the process is
5445 already gone, in which case we simply ignore attempts
5446 to change its registers. See also the related
5447 comment in linux_resume_one_lwp. */
5453 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5456 else if (regset
->type
== GENERAL_REGS
)
5457 saw_general_regs
= 1;
5460 if (saw_general_regs
)
5466 #else /* !HAVE_LINUX_REGSETS */
5468 #define use_linux_regsets 0
5469 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5470 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5474 /* Return 1 if register REGNO is supported by one of the regset ptrace
5475 calls or 0 if it has to be transferred individually. */
5478 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5480 unsigned char mask
= 1 << (regno
% 8);
5481 size_t index
= regno
/ 8;
5483 return (use_linux_regsets
5484 && (regs_info
->regset_bitmap
== NULL
5485 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5488 #ifdef HAVE_LINUX_USRREGS
5491 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5495 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5496 error ("Invalid register number %d.", regnum
);
5498 addr
= usrregs
->regmap
[regnum
];
5503 /* Fetch one register. */
5505 fetch_register (const struct usrregs_info
*usrregs
,
5506 struct regcache
*regcache
, int regno
)
5513 if (regno
>= usrregs
->num_regs
)
5515 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5518 regaddr
= register_addr (usrregs
, regno
);
5522 size
= ((register_size (regcache
->tdesc
, regno
)
5523 + sizeof (PTRACE_XFER_TYPE
) - 1)
5524 & -sizeof (PTRACE_XFER_TYPE
));
5525 buf
= (char *) alloca (size
);
5527 pid
= lwpid_of (current_thread
);
5528 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5531 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5532 ptrace (PTRACE_PEEKUSER
, pid
,
5533 /* Coerce to a uintptr_t first to avoid potential gcc warning
5534 of coercing an 8 byte integer to a 4 byte pointer. */
5535 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5536 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5539 /* Mark register REGNO unavailable. */
5540 supply_register (regcache
, regno
, NULL
);
5545 if (the_low_target
.supply_ptrace_register
)
5546 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5548 supply_register (regcache
, regno
, buf
);
5551 /* Store one register. */
5553 store_register (const struct usrregs_info
*usrregs
,
5554 struct regcache
*regcache
, int regno
)
5561 if (regno
>= usrregs
->num_regs
)
5563 if ((*the_low_target
.cannot_store_register
) (regno
))
5566 regaddr
= register_addr (usrregs
, regno
);
5570 size
= ((register_size (regcache
->tdesc
, regno
)
5571 + sizeof (PTRACE_XFER_TYPE
) - 1)
5572 & -sizeof (PTRACE_XFER_TYPE
));
5573 buf
= (char *) alloca (size
);
5574 memset (buf
, 0, size
);
5576 if (the_low_target
.collect_ptrace_register
)
5577 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5579 collect_register (regcache
, regno
, buf
);
5581 pid
= lwpid_of (current_thread
);
5582 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5585 ptrace (PTRACE_POKEUSER
, pid
,
5586 /* Coerce to a uintptr_t first to avoid potential gcc warning
5587 about coercing an 8 byte integer to a 4 byte pointer. */
5588 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5589 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5592 /* At this point, ESRCH should mean the process is
5593 already gone, in which case we simply ignore attempts
5594 to change its registers. See also the related
5595 comment in linux_resume_one_lwp. */
5599 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5600 error ("writing register %d: %s", regno
, strerror (errno
));
5602 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5606 /* Fetch all registers, or just one, from the child process.
5607 If REGNO is -1, do this for all registers, skipping any that are
5608 assumed to have been retrieved by regsets_fetch_inferior_registers,
5609 unless ALL is non-zero.
5610 Otherwise, REGNO specifies which register (so we can save time). */
5612 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5613 struct regcache
*regcache
, int regno
, int all
)
5615 struct usrregs_info
*usr
= regs_info
->usrregs
;
5619 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5620 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5621 fetch_register (usr
, regcache
, regno
);
5624 fetch_register (usr
, regcache
, regno
);
5627 /* Store our register values back into the inferior.
5628 If REGNO is -1, do this for all registers, skipping any that are
5629 assumed to have been saved by regsets_store_inferior_registers,
5630 unless ALL is non-zero.
5631 Otherwise, REGNO specifies which register (so we can save time). */
5633 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5634 struct regcache
*regcache
, int regno
, int all
)
5636 struct usrregs_info
*usr
= regs_info
->usrregs
;
5640 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5641 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5642 store_register (usr
, regcache
, regno
);
5645 store_register (usr
, regcache
, regno
);
5648 #else /* !HAVE_LINUX_USRREGS */
5650 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5651 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5657 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5661 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5665 if (the_low_target
.fetch_register
!= NULL
5666 && regs_info
->usrregs
!= NULL
)
5667 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5668 (*the_low_target
.fetch_register
) (regcache
, regno
);
5670 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5671 if (regs_info
->usrregs
!= NULL
)
5672 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5676 if (the_low_target
.fetch_register
!= NULL
5677 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5680 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5682 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5684 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5685 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5690 linux_store_registers (struct regcache
*regcache
, int regno
)
5694 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5698 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5700 if (regs_info
->usrregs
!= NULL
)
5701 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5705 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5707 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5709 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5710 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5715 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5716 to debugger memory starting at MYADDR. */
5719 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5721 int pid
= lwpid_of (current_thread
);
5722 PTRACE_XFER_TYPE
*buffer
;
5730 /* Try using /proc. Don't bother for one word. */
5731 if (len
>= 3 * sizeof (long))
5735 /* We could keep this file open and cache it - possibly one per
5736 thread. That requires some juggling, but is even faster. */
5737 sprintf (filename
, "/proc/%d/mem", pid
);
5738 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5742 /* If pread64 is available, use it. It's faster if the kernel
5743 supports it (only one syscall), and it's 64-bit safe even on
5744 32-bit platforms (for instance, SPARC debugging a SPARC64
5747 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5750 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5751 bytes
= read (fd
, myaddr
, len
);
5758 /* Some data was read, we'll try to get the rest with ptrace. */
5768 /* Round starting address down to longword boundary. */
5769 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5770 /* Round ending address up; get number of longwords that makes. */
5771 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5772 / sizeof (PTRACE_XFER_TYPE
));
5773 /* Allocate buffer of that many longwords. */
5774 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5776 /* Read all the longwords */
5778 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5780 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5781 about coercing an 8 byte integer to a 4 byte pointer. */
5782 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5783 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5784 (PTRACE_TYPE_ARG4
) 0);
5790 /* Copy appropriate bytes out of the buffer. */
5793 i
*= sizeof (PTRACE_XFER_TYPE
);
5794 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5796 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5803 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5804 memory at MEMADDR. On failure (cannot write to the inferior)
5805 returns the value of errno. Always succeeds if LEN is zero. */
5808 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5811 /* Round starting address down to longword boundary. */
5812 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5813 /* Round ending address up; get number of longwords that makes. */
5815 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5816 / sizeof (PTRACE_XFER_TYPE
);
5818 /* Allocate buffer of that many longwords. */
5819 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5821 int pid
= lwpid_of (current_thread
);
5825 /* Zero length write always succeeds. */
5831 /* Dump up to four bytes. */
5832 char str
[4 * 2 + 1];
5834 int dump
= len
< 4 ? len
: 4;
5836 for (i
= 0; i
< dump
; i
++)
5838 sprintf (p
, "%02x", myaddr
[i
]);
5843 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5844 str
, (long) memaddr
, pid
);
5847 /* Fill start and end extra bytes of buffer with existing memory data. */
5850 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5851 about coercing an 8 byte integer to a 4 byte pointer. */
5852 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5853 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5854 (PTRACE_TYPE_ARG4
) 0);
5862 = ptrace (PTRACE_PEEKTEXT
, pid
,
5863 /* Coerce to a uintptr_t first to avoid potential gcc warning
5864 about coercing an 8 byte integer to a 4 byte pointer. */
5865 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5866 * sizeof (PTRACE_XFER_TYPE
)),
5867 (PTRACE_TYPE_ARG4
) 0);
5872 /* Copy data to be written over corresponding part of buffer. */
5874 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5877 /* Write the entire buffer. */
5879 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5882 ptrace (PTRACE_POKETEXT
, pid
,
5883 /* Coerce to a uintptr_t first to avoid potential gcc warning
5884 about coercing an 8 byte integer to a 4 byte pointer. */
5885 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5886 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5895 linux_look_up_symbols (void)
5897 #ifdef USE_THREAD_DB
5898 struct process_info
*proc
= current_process ();
5900 if (proc
->priv
->thread_db
!= NULL
)
5908 linux_request_interrupt (void)
5910 /* Send a SIGINT to the process group. This acts just like the user
5911 typed a ^C on the controlling terminal. */
5912 kill (-signal_pid
, SIGINT
);
5915 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5916 to debugger memory starting at MYADDR. */
5919 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5921 char filename
[PATH_MAX
];
5923 int pid
= lwpid_of (current_thread
);
5925 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5927 fd
= open (filename
, O_RDONLY
);
5931 if (offset
!= (CORE_ADDR
) 0
5932 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5935 n
= read (fd
, myaddr
, len
);
5942 /* These breakpoint and watchpoint related wrapper functions simply
5943 pass on the function call if the target has registered a
5944 corresponding function. */
5947 linux_supports_z_point_type (char z_type
)
5949 return (the_low_target
.supports_z_point_type
!= NULL
5950 && the_low_target
.supports_z_point_type (z_type
));
5954 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5955 int size
, struct raw_breakpoint
*bp
)
5957 if (type
== raw_bkpt_type_sw
)
5958 return insert_memory_breakpoint (bp
);
5959 else if (the_low_target
.insert_point
!= NULL
)
5960 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5962 /* Unsupported (see target.h). */
5967 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5968 int size
, struct raw_breakpoint
*bp
)
5970 if (type
== raw_bkpt_type_sw
)
5971 return remove_memory_breakpoint (bp
);
5972 else if (the_low_target
.remove_point
!= NULL
)
5973 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5975 /* Unsupported (see target.h). */
5979 /* Implement the to_stopped_by_sw_breakpoint target_ops
5983 linux_stopped_by_sw_breakpoint (void)
5985 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5987 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5990 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5994 linux_supports_stopped_by_sw_breakpoint (void)
5996 return USE_SIGTRAP_SIGINFO
;
5999 /* Implement the to_stopped_by_hw_breakpoint target_ops
6003 linux_stopped_by_hw_breakpoint (void)
6005 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6007 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
6010 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6014 linux_supports_stopped_by_hw_breakpoint (void)
6016 return USE_SIGTRAP_SIGINFO
;
6019 /* Implement the supports_hardware_single_step target_ops method. */
6022 linux_supports_hardware_single_step (void)
6024 return can_hardware_single_step ();
6028 linux_supports_software_single_step (void)
6030 return can_software_single_step ();
6034 linux_stopped_by_watchpoint (void)
6036 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6038 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
6042 linux_stopped_data_address (void)
6044 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6046 return lwp
->stopped_data_address
;
6049 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6050 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6051 && defined(PT_TEXT_END_ADDR)
6053 /* This is only used for targets that define PT_TEXT_ADDR,
6054 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6055 the target has different ways of acquiring this information, like
6058 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6059 to tell gdb about. */
6062 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
6064 unsigned long text
, text_end
, data
;
6065 int pid
= lwpid_of (current_thread
);
6069 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
6070 (PTRACE_TYPE_ARG4
) 0);
6071 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
6072 (PTRACE_TYPE_ARG4
) 0);
6073 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
6074 (PTRACE_TYPE_ARG4
) 0);
6078 /* Both text and data offsets produced at compile-time (and so
6079 used by gdb) are relative to the beginning of the program,
6080 with the data segment immediately following the text segment.
6081 However, the actual runtime layout in memory may put the data
6082 somewhere else, so when we send gdb a data base-address, we
6083 use the real data base address and subtract the compile-time
6084 data base-address from it (which is just the length of the
6085 text segment). BSS immediately follows data in both
6088 *data_p
= data
- (text_end
- text
);
6097 linux_qxfer_osdata (const char *annex
,
6098 unsigned char *readbuf
, unsigned const char *writebuf
,
6099 CORE_ADDR offset
, int len
)
6101 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
6104 /* Convert a native/host siginfo object, into/from the siginfo in the
6105 layout of the inferiors' architecture. */
6108 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
6112 if (the_low_target
.siginfo_fixup
!= NULL
)
6113 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
6115 /* If there was no callback, or the callback didn't do anything,
6116 then just do a straight memcpy. */
6120 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6122 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6127 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6128 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6132 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6134 if (current_thread
== NULL
)
6137 pid
= lwpid_of (current_thread
);
6140 debug_printf ("%s siginfo for lwp %d.\n",
6141 readbuf
!= NULL
? "Reading" : "Writing",
6144 if (offset
>= sizeof (siginfo
))
6147 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6150 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6151 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6152 inferior with a 64-bit GDBSERVER should look the same as debugging it
6153 with a 32-bit GDBSERVER, we need to convert it. */
6154 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6156 if (offset
+ len
> sizeof (siginfo
))
6157 len
= sizeof (siginfo
) - offset
;
6159 if (readbuf
!= NULL
)
6160 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6163 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6165 /* Convert back to ptrace layout before flushing it out. */
6166 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6168 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6175 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6176 so we notice when children change state; as the handler for the
6177 sigsuspend in my_waitpid. */
6180 sigchld_handler (int signo
)
6182 int old_errno
= errno
;
6188 /* Use the async signal safe debug function. */
6189 if (debug_write ("sigchld_handler\n",
6190 sizeof ("sigchld_handler\n") - 1) < 0)
6191 break; /* just ignore */
6195 if (target_is_async_p ())
6196 async_file_mark (); /* trigger a linux_wait */
6202 linux_supports_non_stop (void)
6208 linux_async (int enable
)
6210 int previous
= target_is_async_p ();
6213 debug_printf ("linux_async (%d), previous=%d\n",
6216 if (previous
!= enable
)
6219 sigemptyset (&mask
);
6220 sigaddset (&mask
, SIGCHLD
);
6222 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6226 if (pipe (linux_event_pipe
) == -1)
6228 linux_event_pipe
[0] = -1;
6229 linux_event_pipe
[1] = -1;
6230 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6232 warning ("creating event pipe failed.");
6236 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6237 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6239 /* Register the event loop handler. */
6240 add_file_handler (linux_event_pipe
[0],
6241 handle_target_event
, NULL
);
6243 /* Always trigger a linux_wait. */
6248 delete_file_handler (linux_event_pipe
[0]);
6250 close (linux_event_pipe
[0]);
6251 close (linux_event_pipe
[1]);
6252 linux_event_pipe
[0] = -1;
6253 linux_event_pipe
[1] = -1;
6256 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6263 linux_start_non_stop (int nonstop
)
6265 /* Register or unregister from event-loop accordingly. */
6266 linux_async (nonstop
);
6268 if (target_is_async_p () != (nonstop
!= 0))
6275 linux_supports_multi_process (void)
6280 /* Check if fork events are supported. */
6283 linux_supports_fork_events (void)
6285 return linux_supports_tracefork ();
6288 /* Check if vfork events are supported. */
6291 linux_supports_vfork_events (void)
6293 return linux_supports_tracefork ();
6296 /* Check if exec events are supported. */
6299 linux_supports_exec_events (void)
6301 return linux_supports_traceexec ();
6304 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6305 ptrace flags for all inferiors. This is in case the new GDB connection
6306 doesn't support the same set of events that the previous one did. */
6309 linux_handle_new_gdb_connection (void)
6311 /* Request that all the lwps reset their ptrace options. */
6312 for_each_thread ([] (thread_info
*thread
)
6314 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6318 /* Stop the lwp so we can modify its ptrace options. */
6319 lwp
->must_set_ptrace_flags
= 1;
6320 linux_stop_lwp (lwp
);
6324 /* Already stopped; go ahead and set the ptrace options. */
6325 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6326 int options
= linux_low_ptrace_options (proc
->attached
);
6328 linux_enable_event_reporting (lwpid_of (thread
), options
);
6329 lwp
->must_set_ptrace_flags
= 0;
6335 linux_supports_disable_randomization (void)
6337 #ifdef HAVE_PERSONALITY
6345 linux_supports_agent (void)
6351 linux_supports_range_stepping (void)
6353 if (can_software_single_step ())
6355 if (*the_low_target
.supports_range_stepping
== NULL
)
6358 return (*the_low_target
.supports_range_stepping
) ();
6361 /* Enumerate spufs IDs for process PID. */
6363 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6369 struct dirent
*entry
;
6371 sprintf (path
, "/proc/%ld/fd", pid
);
6372 dir
= opendir (path
);
6377 while ((entry
= readdir (dir
)) != NULL
)
6383 fd
= atoi (entry
->d_name
);
6387 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6388 if (stat (path
, &st
) != 0)
6390 if (!S_ISDIR (st
.st_mode
))
6393 if (statfs (path
, &stfs
) != 0)
6395 if (stfs
.f_type
!= SPUFS_MAGIC
)
6398 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6400 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6410 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6411 object type, using the /proc file system. */
6413 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6414 unsigned const char *writebuf
,
6415 CORE_ADDR offset
, int len
)
6417 long pid
= lwpid_of (current_thread
);
6422 if (!writebuf
&& !readbuf
)
6430 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6433 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6434 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6439 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6446 ret
= write (fd
, writebuf
, (size_t) len
);
6448 ret
= read (fd
, readbuf
, (size_t) len
);
6454 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6455 struct target_loadseg
6457 /* Core address to which the segment is mapped. */
6459 /* VMA recorded in the program header. */
6461 /* Size of this segment in memory. */
6465 # if defined PT_GETDSBT
6466 struct target_loadmap
6468 /* Protocol version number, must be zero. */
6470 /* Pointer to the DSBT table, its size, and the DSBT index. */
6471 unsigned *dsbt_table
;
6472 unsigned dsbt_size
, dsbt_index
;
6473 /* Number of segments in this map. */
6475 /* The actual memory map. */
6476 struct target_loadseg segs
[/*nsegs*/];
6478 # define LINUX_LOADMAP PT_GETDSBT
6479 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6480 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6482 struct target_loadmap
6484 /* Protocol version number, must be zero. */
6486 /* Number of segments in this map. */
6488 /* The actual memory map. */
6489 struct target_loadseg segs
[/*nsegs*/];
6491 # define LINUX_LOADMAP PTRACE_GETFDPIC
6492 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6493 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6497 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6498 unsigned char *myaddr
, unsigned int len
)
6500 int pid
= lwpid_of (current_thread
);
6502 struct target_loadmap
*data
= NULL
;
6503 unsigned int actual_length
, copy_length
;
6505 if (strcmp (annex
, "exec") == 0)
6506 addr
= (int) LINUX_LOADMAP_EXEC
;
6507 else if (strcmp (annex
, "interp") == 0)
6508 addr
= (int) LINUX_LOADMAP_INTERP
;
6512 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6518 actual_length
= sizeof (struct target_loadmap
)
6519 + sizeof (struct target_loadseg
) * data
->nsegs
;
6521 if (offset
< 0 || offset
> actual_length
)
6524 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6525 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6529 # define linux_read_loadmap NULL
6530 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6533 linux_process_qsupported (char **features
, int count
)
6535 if (the_low_target
.process_qsupported
!= NULL
)
6536 the_low_target
.process_qsupported (features
, count
);
6540 linux_supports_catch_syscall (void)
6542 return (the_low_target
.get_syscall_trapinfo
!= NULL
6543 && linux_supports_tracesysgood ());
6547 linux_get_ipa_tdesc_idx (void)
6549 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6552 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6556 linux_supports_tracepoints (void)
6558 if (*the_low_target
.supports_tracepoints
== NULL
)
6561 return (*the_low_target
.supports_tracepoints
) ();
6565 linux_read_pc (struct regcache
*regcache
)
6567 if (the_low_target
.get_pc
== NULL
)
6570 return (*the_low_target
.get_pc
) (regcache
);
6574 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6576 gdb_assert (the_low_target
.set_pc
!= NULL
);
6578 (*the_low_target
.set_pc
) (regcache
, pc
);
6582 linux_thread_stopped (struct thread_info
*thread
)
6584 return get_thread_lwp (thread
)->stopped
;
6587 /* This exposes stop-all-threads functionality to other modules. */
6590 linux_pause_all (int freeze
)
6592 stop_all_lwps (freeze
, NULL
);
6595 /* This exposes unstop-all-threads functionality to other gdbserver
6599 linux_unpause_all (int unfreeze
)
6601 unstop_all_lwps (unfreeze
, NULL
);
6605 linux_prepare_to_access_memory (void)
6607 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6610 linux_pause_all (1);
6615 linux_done_accessing_memory (void)
6617 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6620 linux_unpause_all (1);
6624 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6625 CORE_ADDR collector
,
6628 CORE_ADDR
*jump_entry
,
6629 CORE_ADDR
*trampoline
,
6630 ULONGEST
*trampoline_size
,
6631 unsigned char *jjump_pad_insn
,
6632 ULONGEST
*jjump_pad_insn_size
,
6633 CORE_ADDR
*adjusted_insn_addr
,
6634 CORE_ADDR
*adjusted_insn_addr_end
,
6637 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6638 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6639 jump_entry
, trampoline
, trampoline_size
,
6640 jjump_pad_insn
, jjump_pad_insn_size
,
6641 adjusted_insn_addr
, adjusted_insn_addr_end
,
6645 static struct emit_ops
*
6646 linux_emit_ops (void)
6648 if (the_low_target
.emit_ops
!= NULL
)
6649 return (*the_low_target
.emit_ops
) ();
6655 linux_get_min_fast_tracepoint_insn_len (void)
6657 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6660 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6663 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6664 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6666 char filename
[PATH_MAX
];
6668 const int auxv_size
= is_elf64
6669 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6670 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6672 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6674 fd
= open (filename
, O_RDONLY
);
6680 while (read (fd
, buf
, auxv_size
) == auxv_size
6681 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6685 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6687 switch (aux
->a_type
)
6690 *phdr_memaddr
= aux
->a_un
.a_val
;
6693 *num_phdr
= aux
->a_un
.a_val
;
6699 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6701 switch (aux
->a_type
)
6704 *phdr_memaddr
= aux
->a_un
.a_val
;
6707 *num_phdr
= aux
->a_un
.a_val
;
6715 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6717 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6718 "phdr_memaddr = %ld, phdr_num = %d",
6719 (long) *phdr_memaddr
, *num_phdr
);
6726 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6729 get_dynamic (const int pid
, const int is_elf64
)
6731 CORE_ADDR phdr_memaddr
, relocation
;
6733 unsigned char *phdr_buf
;
6734 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6736 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6739 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6740 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6742 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6745 /* Compute relocation: it is expected to be 0 for "regular" executables,
6746 non-zero for PIE ones. */
6748 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6751 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6753 if (p
->p_type
== PT_PHDR
)
6754 relocation
= phdr_memaddr
- p
->p_vaddr
;
6758 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6760 if (p
->p_type
== PT_PHDR
)
6761 relocation
= phdr_memaddr
- p
->p_vaddr
;
6764 if (relocation
== -1)
6766 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6767 any real world executables, including PIE executables, have always
6768 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6769 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6770 or present DT_DEBUG anyway (fpc binaries are statically linked).
6772 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6774 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6779 for (i
= 0; i
< num_phdr
; i
++)
6783 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6785 if (p
->p_type
== PT_DYNAMIC
)
6786 return p
->p_vaddr
+ relocation
;
6790 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6792 if (p
->p_type
== PT_DYNAMIC
)
6793 return p
->p_vaddr
+ relocation
;
6800 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6801 can be 0 if the inferior does not yet have the library list initialized.
6802 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6803 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6806 get_r_debug (const int pid
, const int is_elf64
)
6808 CORE_ADDR dynamic_memaddr
;
6809 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6810 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6813 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6814 if (dynamic_memaddr
== 0)
6817 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6821 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6822 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6826 unsigned char buf
[sizeof (Elf64_Xword
)];
6830 #ifdef DT_MIPS_RLD_MAP
6831 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6833 if (linux_read_memory (dyn
->d_un
.d_val
,
6834 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6839 #endif /* DT_MIPS_RLD_MAP */
6840 #ifdef DT_MIPS_RLD_MAP_REL
6841 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6843 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6844 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6849 #endif /* DT_MIPS_RLD_MAP_REL */
6851 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6852 map
= dyn
->d_un
.d_val
;
6854 if (dyn
->d_tag
== DT_NULL
)
6859 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6860 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6864 unsigned char buf
[sizeof (Elf32_Word
)];
6868 #ifdef DT_MIPS_RLD_MAP
6869 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6871 if (linux_read_memory (dyn
->d_un
.d_val
,
6872 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6877 #endif /* DT_MIPS_RLD_MAP */
6878 #ifdef DT_MIPS_RLD_MAP_REL
6879 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6881 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6882 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6887 #endif /* DT_MIPS_RLD_MAP_REL */
6889 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6890 map
= dyn
->d_un
.d_val
;
6892 if (dyn
->d_tag
== DT_NULL
)
6896 dynamic_memaddr
+= dyn_size
;
6902 /* Read one pointer from MEMADDR in the inferior. */
6905 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6909 /* Go through a union so this works on either big or little endian
6910 hosts, when the inferior's pointer size is smaller than the size
6911 of CORE_ADDR. It is assumed the inferior's endianness is the
6912 same of the superior's. */
6915 CORE_ADDR core_addr
;
6920 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6923 if (ptr_size
== sizeof (CORE_ADDR
))
6924 *ptr
= addr
.core_addr
;
6925 else if (ptr_size
== sizeof (unsigned int))
6928 gdb_assert_not_reached ("unhandled pointer size");
6933 struct link_map_offsets
6935 /* Offset and size of r_debug.r_version. */
6936 int r_version_offset
;
6938 /* Offset and size of r_debug.r_map. */
6941 /* Offset to l_addr field in struct link_map. */
6944 /* Offset to l_name field in struct link_map. */
6947 /* Offset to l_ld field in struct link_map. */
6950 /* Offset to l_next field in struct link_map. */
6953 /* Offset to l_prev field in struct link_map. */
6957 /* Construct qXfer:libraries-svr4:read reply. */
6960 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6961 unsigned const char *writebuf
,
6962 CORE_ADDR offset
, int len
)
6964 struct process_info_private
*const priv
= current_process ()->priv
;
6965 char filename
[PATH_MAX
];
6968 static const struct link_map_offsets lmo_32bit_offsets
=
6970 0, /* r_version offset. */
6971 4, /* r_debug.r_map offset. */
6972 0, /* l_addr offset in link_map. */
6973 4, /* l_name offset in link_map. */
6974 8, /* l_ld offset in link_map. */
6975 12, /* l_next offset in link_map. */
6976 16 /* l_prev offset in link_map. */
6979 static const struct link_map_offsets lmo_64bit_offsets
=
6981 0, /* r_version offset. */
6982 8, /* r_debug.r_map offset. */
6983 0, /* l_addr offset in link_map. */
6984 8, /* l_name offset in link_map. */
6985 16, /* l_ld offset in link_map. */
6986 24, /* l_next offset in link_map. */
6987 32 /* l_prev offset in link_map. */
6989 const struct link_map_offsets
*lmo
;
6990 unsigned int machine
;
6992 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6993 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6994 int header_done
= 0;
6996 if (writebuf
!= NULL
)
6998 if (readbuf
== NULL
)
7001 pid
= lwpid_of (current_thread
);
7002 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
7003 is_elf64
= elf_64_file_p (filename
, &machine
);
7004 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
7005 ptr_size
= is_elf64
? 8 : 4;
7007 while (annex
[0] != '\0')
7013 sep
= strchr (annex
, '=');
7017 name_len
= sep
- annex
;
7018 if (name_len
== 5 && startswith (annex
, "start"))
7020 else if (name_len
== 4 && startswith (annex
, "prev"))
7024 annex
= strchr (sep
, ';');
7031 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
7038 if (priv
->r_debug
== 0)
7039 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
7041 /* We failed to find DT_DEBUG. Such situation will not change
7042 for this inferior - do not retry it. Report it to GDB as
7043 E01, see for the reasons at the GDB solib-svr4.c side. */
7044 if (priv
->r_debug
== (CORE_ADDR
) -1)
7047 if (priv
->r_debug
!= 0)
7049 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
7050 (unsigned char *) &r_version
,
7051 sizeof (r_version
)) != 0
7054 warning ("unexpected r_debug version %d", r_version
);
7056 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
7057 &lm_addr
, ptr_size
) != 0)
7059 warning ("unable to read r_map from 0x%lx",
7060 (long) priv
->r_debug
+ lmo
->r_map_offset
);
7065 std::string document
= "<library-list-svr4 version=\"1.0\"";
7068 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
7069 &l_name
, ptr_size
) == 0
7070 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
7071 &l_addr
, ptr_size
) == 0
7072 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
7073 &l_ld
, ptr_size
) == 0
7074 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
7075 &l_prev
, ptr_size
) == 0
7076 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
7077 &l_next
, ptr_size
) == 0)
7079 unsigned char libname
[PATH_MAX
];
7081 if (lm_prev
!= l_prev
)
7083 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7084 (long) lm_prev
, (long) l_prev
);
7088 /* Ignore the first entry even if it has valid name as the first entry
7089 corresponds to the main executable. The first entry should not be
7090 skipped if the dynamic loader was loaded late by a static executable
7091 (see solib-svr4.c parameter ignore_first). But in such case the main
7092 executable does not have PT_DYNAMIC present and this function already
7093 exited above due to failed get_r_debug. */
7095 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7098 /* Not checking for error because reading may stop before
7099 we've got PATH_MAX worth of characters. */
7101 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7102 libname
[sizeof (libname
) - 1] = '\0';
7103 if (libname
[0] != '\0')
7107 /* Terminate `<library-list-svr4'. */
7112 string_appendf (document
, "<library name=\"");
7113 xml_escape_text_append (&document
, (char *) libname
);
7114 string_appendf (document
, "\" lm=\"0x%lx\" "
7115 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7116 (unsigned long) lm_addr
, (unsigned long) l_addr
,
7117 (unsigned long) l_ld
);
7127 /* Empty list; terminate `<library-list-svr4'. */
7131 document
+= "</library-list-svr4>";
7133 int document_len
= document
.length ();
7134 if (offset
< document_len
)
7135 document_len
-= offset
;
7138 if (len
> document_len
)
7141 memcpy (readbuf
, document
.data () + offset
, len
);
7146 #ifdef HAVE_LINUX_BTRACE
7148 /* See to_disable_btrace target method. */
7151 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7153 enum btrace_error err
;
7155 err
= linux_disable_btrace (tinfo
);
7156 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7159 /* Encode an Intel Processor Trace configuration. */
7162 linux_low_encode_pt_config (struct buffer
*buffer
,
7163 const struct btrace_data_pt_config
*config
)
7165 buffer_grow_str (buffer
, "<pt-config>\n");
7167 switch (config
->cpu
.vendor
)
7170 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7171 "model=\"%u\" stepping=\"%u\"/>\n",
7172 config
->cpu
.family
, config
->cpu
.model
,
7173 config
->cpu
.stepping
);
7180 buffer_grow_str (buffer
, "</pt-config>\n");
7183 /* Encode a raw buffer. */
7186 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7192 /* We use hex encoding - see gdbsupport/rsp-low.h. */
7193 buffer_grow_str (buffer
, "<raw>\n");
7199 elem
[0] = tohex ((*data
>> 4) & 0xf);
7200 elem
[1] = tohex (*data
++ & 0xf);
7202 buffer_grow (buffer
, elem
, 2);
7205 buffer_grow_str (buffer
, "</raw>\n");
7208 /* See to_read_btrace target method. */
7211 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7212 enum btrace_read_type type
)
7214 struct btrace_data btrace
;
7215 struct btrace_block
*block
;
7216 enum btrace_error err
;
7219 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7220 if (err
!= BTRACE_ERR_NONE
)
7222 if (err
== BTRACE_ERR_OVERFLOW
)
7223 buffer_grow_str0 (buffer
, "E.Overflow.");
7225 buffer_grow_str0 (buffer
, "E.Generic Error.");
7230 switch (btrace
.format
)
7232 case BTRACE_FORMAT_NONE
:
7233 buffer_grow_str0 (buffer
, "E.No Trace.");
7236 case BTRACE_FORMAT_BTS
:
7237 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7238 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7241 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7243 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7244 paddress (block
->begin
), paddress (block
->end
));
7246 buffer_grow_str0 (buffer
, "</btrace>\n");
7249 case BTRACE_FORMAT_PT
:
7250 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7251 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7252 buffer_grow_str (buffer
, "<pt>\n");
7254 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7256 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7257 btrace
.variant
.pt
.size
);
7259 buffer_grow_str (buffer
, "</pt>\n");
7260 buffer_grow_str0 (buffer
, "</btrace>\n");
7264 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7271 /* See to_btrace_conf target method. */
7274 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7275 struct buffer
*buffer
)
7277 const struct btrace_config
*conf
;
7279 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7280 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7282 conf
= linux_btrace_conf (tinfo
);
7285 switch (conf
->format
)
7287 case BTRACE_FORMAT_NONE
:
7290 case BTRACE_FORMAT_BTS
:
7291 buffer_xml_printf (buffer
, "<bts");
7292 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7293 buffer_xml_printf (buffer
, " />\n");
7296 case BTRACE_FORMAT_PT
:
7297 buffer_xml_printf (buffer
, "<pt");
7298 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7299 buffer_xml_printf (buffer
, "/>\n");
7304 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7307 #endif /* HAVE_LINUX_BTRACE */
7309 /* See nat/linux-nat.h. */
7312 current_lwp_ptid (void)
7314 return ptid_of (current_thread
);
7317 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7320 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7322 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7323 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7325 return default_breakpoint_kind_from_pc (pcptr
);
7328 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7330 static const gdb_byte
*
7331 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7333 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7335 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7338 /* Implementation of the target_ops method
7339 "breakpoint_kind_from_current_state". */
7342 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7344 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7345 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7347 return linux_breakpoint_kind_from_pc (pcptr
);
7350 /* Default implementation of linux_target_ops method "set_pc" for
7351 32-bit pc register which is literally named "pc". */
7354 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7356 uint32_t newpc
= pc
;
7358 supply_register_by_name (regcache
, "pc", &newpc
);
7361 /* Default implementation of linux_target_ops method "get_pc" for
7362 32-bit pc register which is literally named "pc". */
7365 linux_get_pc_32bit (struct regcache
*regcache
)
7369 collect_register_by_name (regcache
, "pc", &pc
);
7371 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7375 /* Default implementation of linux_target_ops method "set_pc" for
7376 64-bit pc register which is literally named "pc". */
7379 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7381 uint64_t newpc
= pc
;
7383 supply_register_by_name (regcache
, "pc", &newpc
);
7386 /* Default implementation of linux_target_ops method "get_pc" for
7387 64-bit pc register which is literally named "pc". */
7390 linux_get_pc_64bit (struct regcache
*regcache
)
7394 collect_register_by_name (regcache
, "pc", &pc
);
7396 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7400 /* See linux-low.h. */
7403 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
7405 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
7408 gdb_assert (wordsize
== 4 || wordsize
== 8);
7410 while ((*the_target
->read_auxv
) (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
7414 uint32_t *data_p
= (uint32_t *) data
;
7415 if (data_p
[0] == match
)
7423 uint64_t *data_p
= (uint64_t *) data
;
7424 if (data_p
[0] == match
)
7431 offset
+= 2 * wordsize
;
7437 /* See linux-low.h. */
7440 linux_get_hwcap (int wordsize
)
7442 CORE_ADDR hwcap
= 0;
7443 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7447 /* See linux-low.h. */
7450 linux_get_hwcap2 (int wordsize
)
7452 CORE_ADDR hwcap2
= 0;
7453 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7457 static struct target_ops linux_target_ops
= {
7458 linux_create_inferior
,
7459 linux_post_create_inferior
,
7468 linux_fetch_registers
,
7469 linux_store_registers
,
7470 linux_prepare_to_access_memory
,
7471 linux_done_accessing_memory
,
7474 linux_look_up_symbols
,
7475 linux_request_interrupt
,
7477 linux_supports_z_point_type
,
7480 linux_stopped_by_sw_breakpoint
,
7481 linux_supports_stopped_by_sw_breakpoint
,
7482 linux_stopped_by_hw_breakpoint
,
7483 linux_supports_stopped_by_hw_breakpoint
,
7484 linux_supports_hardware_single_step
,
7485 linux_stopped_by_watchpoint
,
7486 linux_stopped_data_address
,
7487 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7488 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7489 && defined(PT_TEXT_END_ADDR)
7494 #ifdef USE_THREAD_DB
7495 thread_db_get_tls_address
,
7500 hostio_last_error_from_errno
,
7503 linux_supports_non_stop
,
7505 linux_start_non_stop
,
7506 linux_supports_multi_process
,
7507 linux_supports_fork_events
,
7508 linux_supports_vfork_events
,
7509 linux_supports_exec_events
,
7510 linux_handle_new_gdb_connection
,
7511 #ifdef USE_THREAD_DB
7512 thread_db_handle_monitor_command
,
7516 linux_common_core_of_thread
,
7518 linux_process_qsupported
,
7519 linux_supports_tracepoints
,
7522 linux_thread_stopped
,
7526 linux_stabilize_threads
,
7527 linux_install_fast_tracepoint_jump_pad
,
7529 linux_supports_disable_randomization
,
7530 linux_get_min_fast_tracepoint_insn_len
,
7531 linux_qxfer_libraries_svr4
,
7532 linux_supports_agent
,
7533 #ifdef HAVE_LINUX_BTRACE
7534 linux_enable_btrace
,
7535 linux_low_disable_btrace
,
7536 linux_low_read_btrace
,
7537 linux_low_btrace_conf
,
7544 linux_supports_range_stepping
,
7545 linux_proc_pid_to_exec_file
,
7546 linux_mntns_open_cloexec
,
7548 linux_mntns_readlink
,
7549 linux_breakpoint_kind_from_pc
,
7550 linux_sw_breakpoint_from_kind
,
7551 linux_proc_tid_get_name
,
7552 linux_breakpoint_kind_from_current_state
,
7553 linux_supports_software_single_step
,
7554 linux_supports_catch_syscall
,
7555 linux_get_ipa_tdesc_idx
,
7557 thread_db_thread_handle
,
7563 #ifdef HAVE_LINUX_REGSETS
7565 initialize_regsets_info (struct regsets_info
*info
)
7567 for (info
->num_regsets
= 0;
7568 info
->regsets
[info
->num_regsets
].size
>= 0;
7569 info
->num_regsets
++)
7575 initialize_low (void)
7577 struct sigaction sigchld_action
;
7579 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7580 set_target_ops (&linux_target_ops
);
7582 linux_ptrace_init_warnings ();
7583 linux_proc_init_warnings ();
7585 sigchld_action
.sa_handler
= sigchld_handler
;
7586 sigemptyset (&sigchld_action
.sa_mask
);
7587 sigchld_action
.sa_flags
= SA_RESTART
;
7588 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7590 initialize_low_arch ();
7592 linux_check_ptrace_features ();