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 "common/agent.h"
24 #include "common/rsp-low.h"
25 #include "common/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "common/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 "common/filestuff.h"
47 #include "tracepoint.h"
50 #include "common/common-inferior.h"
51 #include "nat/fork-inferior.h"
52 #include "common/environ.h"
53 #include "common/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
78 /* Some targets did not define these ptrace constants from the start,
79 so gdbserver defines them locally here. In the future, these may
80 be removed after they are added to asm/ptrace.h. */
81 #if !(defined(PT_TEXT_ADDR) \
82 || defined(PT_DATA_ADDR) \
83 || defined(PT_TEXT_END_ADDR))
84 #if defined(__mcoldfire__)
85 /* These are still undefined in 3.10 kernels. */
86 #define PT_TEXT_ADDR 49*4
87 #define PT_DATA_ADDR 50*4
88 #define PT_TEXT_END_ADDR 51*4
89 /* BFIN already defines these since at least 2.6.32 kernels. */
91 #define PT_TEXT_ADDR 220
92 #define PT_TEXT_END_ADDR 224
93 #define PT_DATA_ADDR 228
94 /* These are still undefined in 3.10 kernels. */
95 #elif defined(__TMS320C6X__)
96 #define PT_TEXT_ADDR (0x10000*4)
97 #define PT_DATA_ADDR (0x10004*4)
98 #define PT_TEXT_END_ADDR (0x10008*4)
102 #ifdef HAVE_LINUX_BTRACE
103 # include "nat/linux-btrace.h"
104 # include "common/btrace-common.h"
107 #ifndef HAVE_ELF32_AUXV_T
108 /* Copied from glibc's elf.h. */
111 uint32_t a_type
; /* Entry type */
114 uint32_t a_val
; /* Integer value */
115 /* We use to have pointer elements added here. We cannot do that,
116 though, since it does not work when using 32-bit definitions
117 on 64-bit platforms and vice versa. */
122 #ifndef HAVE_ELF64_AUXV_T
123 /* Copied from glibc's elf.h. */
126 uint64_t a_type
; /* Entry type */
129 uint64_t a_val
; /* Integer value */
130 /* We use to have pointer elements added here. We cannot do that,
131 though, since it does not work when using 32-bit definitions
132 on 64-bit platforms and vice versa. */
137 /* Does the current host support PTRACE_GETREGSET? */
138 int have_ptrace_getregset
= -1;
142 /* See nat/linux-nat.h. */
145 ptid_of_lwp (struct lwp_info
*lwp
)
147 return ptid_of (get_lwp_thread (lwp
));
150 /* See nat/linux-nat.h. */
153 lwp_set_arch_private_info (struct lwp_info
*lwp
,
154 struct arch_lwp_info
*info
)
156 lwp
->arch_private
= info
;
159 /* See nat/linux-nat.h. */
161 struct arch_lwp_info
*
162 lwp_arch_private_info (struct lwp_info
*lwp
)
164 return lwp
->arch_private
;
167 /* See nat/linux-nat.h. */
170 lwp_is_stopped (struct lwp_info
*lwp
)
175 /* See nat/linux-nat.h. */
177 enum target_stop_reason
178 lwp_stop_reason (struct lwp_info
*lwp
)
180 return lwp
->stop_reason
;
183 /* See nat/linux-nat.h. */
186 lwp_is_stepping (struct lwp_info
*lwp
)
188 return lwp
->stepping
;
191 /* A list of all unknown processes which receive stop signals. Some
192 other process will presumably claim each of these as forked
193 children momentarily. */
195 struct simple_pid_list
197 /* The process ID. */
200 /* The status as reported by waitpid. */
204 struct simple_pid_list
*next
;
206 struct simple_pid_list
*stopped_pids
;
208 /* Trivial list manipulation functions to keep track of a list of new
209 stopped processes. */
212 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
214 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
217 new_pid
->status
= status
;
218 new_pid
->next
= *listp
;
223 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
225 struct simple_pid_list
**p
;
227 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
228 if ((*p
)->pid
== pid
)
230 struct simple_pid_list
*next
= (*p
)->next
;
232 *statusp
= (*p
)->status
;
240 enum stopping_threads_kind
242 /* Not stopping threads presently. */
243 NOT_STOPPING_THREADS
,
245 /* Stopping threads. */
248 /* Stopping and suspending threads. */
249 STOPPING_AND_SUSPENDING_THREADS
252 /* This is set while stop_all_lwps is in effect. */
253 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
255 /* FIXME make into a target method? */
256 int using_threads
= 1;
258 /* True if we're presently stabilizing threads (moving them out of
260 static int stabilizing_threads
;
262 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
263 int step
, int signal
, siginfo_t
*info
);
264 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
265 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
266 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
267 static void unsuspend_all_lwps (struct lwp_info
*except
);
268 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
269 int *wstat
, int options
);
270 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
271 static struct lwp_info
*add_lwp (ptid_t ptid
);
272 static void linux_mourn (struct process_info
*process
);
273 static int linux_stopped_by_watchpoint (void);
274 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
275 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
276 static void proceed_all_lwps (void);
277 static int finish_step_over (struct lwp_info
*lwp
);
278 static int kill_lwp (unsigned long lwpid
, int signo
);
279 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
280 static void complete_ongoing_step_over (void);
281 static int linux_low_ptrace_options (int attached
);
282 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
283 static void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
285 /* When the event-loop is doing a step-over, this points at the thread
287 ptid_t step_over_bkpt
;
289 /* True if the low target can hardware single-step. */
292 can_hardware_single_step (void)
294 if (the_low_target
.supports_hardware_single_step
!= NULL
)
295 return the_low_target
.supports_hardware_single_step ();
300 /* True if the low target can software single-step. Such targets
301 implement the GET_NEXT_PCS callback. */
304 can_software_single_step (void)
306 return (the_low_target
.get_next_pcs
!= NULL
);
309 /* True if the low target supports memory breakpoints. If so, we'll
310 have a GET_PC implementation. */
313 supports_breakpoints (void)
315 return (the_low_target
.get_pc
!= NULL
);
318 /* Returns true if this target can support fast tracepoints. This
319 does not mean that the in-process agent has been loaded in the
323 supports_fast_tracepoints (void)
325 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
328 /* True if LWP is stopped in its stepping range. */
331 lwp_in_step_range (struct lwp_info
*lwp
)
333 CORE_ADDR pc
= lwp
->stop_pc
;
335 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
338 struct pending_signals
342 struct pending_signals
*prev
;
345 /* The read/write ends of the pipe registered as waitable file in the
347 static int linux_event_pipe
[2] = { -1, -1 };
349 /* True if we're currently in async mode. */
350 #define target_is_async_p() (linux_event_pipe[0] != -1)
352 static void send_sigstop (struct lwp_info
*lwp
);
353 static void wait_for_sigstop (void);
355 /* Return non-zero if HEADER is a 64-bit ELF file. */
358 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
360 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
361 && header
->e_ident
[EI_MAG1
] == ELFMAG1
362 && header
->e_ident
[EI_MAG2
] == ELFMAG2
363 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
365 *machine
= header
->e_machine
;
366 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
373 /* Return non-zero if FILE is a 64-bit ELF file,
374 zero if the file is not a 64-bit ELF file,
375 and -1 if the file is not accessible or doesn't exist. */
378 elf_64_file_p (const char *file
, unsigned int *machine
)
383 fd
= open (file
, O_RDONLY
);
387 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
394 return elf_64_header_p (&header
, machine
);
397 /* Accepts an integer PID; Returns true if the executable PID is
398 running is a 64-bit ELF file.. */
401 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
405 sprintf (file
, "/proc/%d/exe", pid
);
406 return elf_64_file_p (file
, machine
);
410 delete_lwp (struct lwp_info
*lwp
)
412 struct thread_info
*thr
= get_lwp_thread (lwp
);
415 debug_printf ("deleting %ld\n", lwpid_of (thr
));
419 if (the_low_target
.delete_thread
!= NULL
)
420 the_low_target
.delete_thread (lwp
->arch_private
);
422 gdb_assert (lwp
->arch_private
== NULL
);
427 /* Add a process to the common process list, and set its private
430 static struct process_info
*
431 linux_add_process (int pid
, int attached
)
433 struct process_info
*proc
;
435 proc
= add_process (pid
, attached
);
436 proc
->priv
= XCNEW (struct process_info_private
);
438 if (the_low_target
.new_process
!= NULL
)
439 proc
->priv
->arch_private
= the_low_target
.new_process ();
444 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
446 /* Call the target arch_setup function on the current thread. */
449 linux_arch_setup (void)
451 the_low_target
.arch_setup ();
454 /* Call the target arch_setup function on THREAD. */
457 linux_arch_setup_thread (struct thread_info
*thread
)
459 struct thread_info
*saved_thread
;
461 saved_thread
= current_thread
;
462 current_thread
= thread
;
466 current_thread
= saved_thread
;
469 /* Handle a GNU/Linux extended wait response. If we see a clone,
470 fork, or vfork event, we need to add the new LWP to our list
471 (and return 0 so as not to report the trap to higher layers).
472 If we see an exec event, we will modify ORIG_EVENT_LWP to point
473 to a new LWP representing the new program. */
476 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
478 client_state
&cs
= get_client_state ();
479 struct lwp_info
*event_lwp
= *orig_event_lwp
;
480 int event
= linux_ptrace_get_extended_event (wstat
);
481 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
482 struct lwp_info
*new_lwp
;
484 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
486 /* All extended events we currently use are mid-syscall. Only
487 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
488 you have to be using PTRACE_SEIZE to get that. */
489 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
491 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
492 || (event
== PTRACE_EVENT_CLONE
))
495 unsigned long new_pid
;
498 /* Get the pid of the new lwp. */
499 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
502 /* If we haven't already seen the new PID stop, wait for it now. */
503 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
505 /* The new child has a pending SIGSTOP. We can't affect it until it
506 hits the SIGSTOP, but we're already attached. */
508 ret
= my_waitpid (new_pid
, &status
, __WALL
);
511 perror_with_name ("waiting for new child");
512 else if (ret
!= new_pid
)
513 warning ("wait returned unexpected PID %d", ret
);
514 else if (!WIFSTOPPED (status
))
515 warning ("wait returned unexpected status 0x%x", status
);
518 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
520 struct process_info
*parent_proc
;
521 struct process_info
*child_proc
;
522 struct lwp_info
*child_lwp
;
523 struct thread_info
*child_thr
;
524 struct target_desc
*tdesc
;
526 ptid
= ptid_t (new_pid
, new_pid
, 0);
530 debug_printf ("HEW: Got fork event from LWP %ld, "
532 ptid_of (event_thr
).lwp (),
536 /* Add the new process to the tables and clone the breakpoint
537 lists of the parent. We need to do this even if the new process
538 will be detached, since we will need the process object and the
539 breakpoints to remove any breakpoints from memory when we
540 detach, and the client side will access registers. */
541 child_proc
= linux_add_process (new_pid
, 0);
542 gdb_assert (child_proc
!= NULL
);
543 child_lwp
= add_lwp (ptid
);
544 gdb_assert (child_lwp
!= NULL
);
545 child_lwp
->stopped
= 1;
546 child_lwp
->must_set_ptrace_flags
= 1;
547 child_lwp
->status_pending_p
= 0;
548 child_thr
= get_lwp_thread (child_lwp
);
549 child_thr
->last_resume_kind
= resume_stop
;
550 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
552 /* If we're suspending all threads, leave this one suspended
553 too. If the fork/clone parent is stepping over a breakpoint,
554 all other threads have been suspended already. Leave the
555 child suspended too. */
556 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
557 || event_lwp
->bp_reinsert
!= 0)
560 debug_printf ("HEW: leaving child suspended\n");
561 child_lwp
->suspended
= 1;
564 parent_proc
= get_thread_process (event_thr
);
565 child_proc
->attached
= parent_proc
->attached
;
567 if (event_lwp
->bp_reinsert
!= 0
568 && can_software_single_step ()
569 && event
== PTRACE_EVENT_VFORK
)
571 /* If we leave single-step breakpoints there, child will
572 hit it, so uninsert single-step breakpoints from parent
573 (and child). Once vfork child is done, reinsert
574 them back to parent. */
575 uninsert_single_step_breakpoints (event_thr
);
578 clone_all_breakpoints (child_thr
, event_thr
);
580 tdesc
= allocate_target_description ();
581 copy_target_description (tdesc
, parent_proc
->tdesc
);
582 child_proc
->tdesc
= tdesc
;
584 /* Clone arch-specific process data. */
585 if (the_low_target
.new_fork
!= NULL
)
586 the_low_target
.new_fork (parent_proc
, child_proc
);
588 /* Save fork info in the parent thread. */
589 if (event
== PTRACE_EVENT_FORK
)
590 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
591 else if (event
== PTRACE_EVENT_VFORK
)
592 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
594 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
596 /* The status_pending field contains bits denoting the
597 extended event, so when the pending event is handled,
598 the handler will look at lwp->waitstatus. */
599 event_lwp
->status_pending_p
= 1;
600 event_lwp
->status_pending
= wstat
;
602 /* Link the threads until the parent event is passed on to
604 event_lwp
->fork_relative
= child_lwp
;
605 child_lwp
->fork_relative
= event_lwp
;
607 /* If the parent thread is doing step-over with single-step
608 breakpoints, the list of single-step breakpoints are cloned
609 from the parent's. Remove them from the child process.
610 In case of vfork, we'll reinsert them back once vforked
612 if (event_lwp
->bp_reinsert
!= 0
613 && can_software_single_step ())
615 /* The child process is forked and stopped, so it is safe
616 to access its memory without stopping all other threads
617 from other processes. */
618 delete_single_step_breakpoints (child_thr
);
620 gdb_assert (has_single_step_breakpoints (event_thr
));
621 gdb_assert (!has_single_step_breakpoints (child_thr
));
624 /* Report the event. */
629 debug_printf ("HEW: Got clone event "
630 "from LWP %ld, new child is LWP %ld\n",
631 lwpid_of (event_thr
), new_pid
);
633 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
634 new_lwp
= add_lwp (ptid
);
636 /* Either we're going to immediately resume the new thread
637 or leave it stopped. linux_resume_one_lwp is a nop if it
638 thinks the thread is currently running, so set this first
639 before calling linux_resume_one_lwp. */
640 new_lwp
->stopped
= 1;
642 /* If we're suspending all threads, leave this one suspended
643 too. If the fork/clone parent is stepping over a breakpoint,
644 all other threads have been suspended already. Leave the
645 child suspended too. */
646 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
647 || event_lwp
->bp_reinsert
!= 0)
648 new_lwp
->suspended
= 1;
650 /* Normally we will get the pending SIGSTOP. But in some cases
651 we might get another signal delivered to the group first.
652 If we do get another signal, be sure not to lose it. */
653 if (WSTOPSIG (status
) != SIGSTOP
)
655 new_lwp
->stop_expected
= 1;
656 new_lwp
->status_pending_p
= 1;
657 new_lwp
->status_pending
= status
;
659 else if (cs
.report_thread_events
)
661 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
662 new_lwp
->status_pending_p
= 1;
663 new_lwp
->status_pending
= status
;
667 thread_db_notice_clone (event_thr
, ptid
);
670 /* Don't report the event. */
673 else if (event
== PTRACE_EVENT_VFORK_DONE
)
675 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
677 if (event_lwp
->bp_reinsert
!= 0 && can_software_single_step ())
679 reinsert_single_step_breakpoints (event_thr
);
681 gdb_assert (has_single_step_breakpoints (event_thr
));
684 /* Report the event. */
687 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
689 struct process_info
*proc
;
690 std::vector
<int> syscalls_to_catch
;
696 debug_printf ("HEW: Got exec event from LWP %ld\n",
697 lwpid_of (event_thr
));
700 /* Get the event ptid. */
701 event_ptid
= ptid_of (event_thr
);
702 event_pid
= event_ptid
.pid ();
704 /* Save the syscall list from the execing process. */
705 proc
= get_thread_process (event_thr
);
706 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
708 /* Delete the execing process and all its threads. */
710 current_thread
= NULL
;
712 /* Create a new process/lwp/thread. */
713 proc
= linux_add_process (event_pid
, 0);
714 event_lwp
= add_lwp (event_ptid
);
715 event_thr
= get_lwp_thread (event_lwp
);
716 gdb_assert (current_thread
== event_thr
);
717 linux_arch_setup_thread (event_thr
);
719 /* Set the event status. */
720 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
721 event_lwp
->waitstatus
.value
.execd_pathname
722 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
724 /* Mark the exec status as pending. */
725 event_lwp
->stopped
= 1;
726 event_lwp
->status_pending_p
= 1;
727 event_lwp
->status_pending
= wstat
;
728 event_thr
->last_resume_kind
= resume_continue
;
729 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
731 /* Update syscall state in the new lwp, effectively mid-syscall too. */
732 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
734 /* Restore the list to catch. Don't rely on the client, which is free
735 to avoid sending a new list when the architecture doesn't change.
736 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
737 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
739 /* Report the event. */
740 *orig_event_lwp
= event_lwp
;
744 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
747 /* Return the PC as read from the regcache of LWP, without any
751 get_pc (struct lwp_info
*lwp
)
753 struct thread_info
*saved_thread
;
754 struct regcache
*regcache
;
757 if (the_low_target
.get_pc
== NULL
)
760 saved_thread
= current_thread
;
761 current_thread
= get_lwp_thread (lwp
);
763 regcache
= get_thread_regcache (current_thread
, 1);
764 pc
= (*the_low_target
.get_pc
) (regcache
);
767 debug_printf ("pc is 0x%lx\n", (long) pc
);
769 current_thread
= saved_thread
;
773 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
774 Fill *SYSNO with the syscall nr trapped. */
777 get_syscall_trapinfo (struct lwp_info
*lwp
, int *sysno
)
779 struct thread_info
*saved_thread
;
780 struct regcache
*regcache
;
782 if (the_low_target
.get_syscall_trapinfo
== NULL
)
784 /* If we cannot get the syscall trapinfo, report an unknown
785 system call number. */
786 *sysno
= UNKNOWN_SYSCALL
;
790 saved_thread
= current_thread
;
791 current_thread
= get_lwp_thread (lwp
);
793 regcache
= get_thread_regcache (current_thread
, 1);
794 (*the_low_target
.get_syscall_trapinfo
) (regcache
, sysno
);
797 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
799 current_thread
= saved_thread
;
802 static int check_stopped_by_watchpoint (struct lwp_info
*child
);
804 /* Called when the LWP stopped for a signal/trap. If it stopped for a
805 trap check what caused it (breakpoint, watchpoint, trace, etc.),
806 and save the result in the LWP's stop_reason field. If it stopped
807 for a breakpoint, decrement the PC if necessary on the lwp's
808 architecture. Returns true if we now have the LWP's stop PC. */
811 save_stop_reason (struct lwp_info
*lwp
)
814 CORE_ADDR sw_breakpoint_pc
;
815 struct thread_info
*saved_thread
;
816 #if USE_SIGTRAP_SIGINFO
820 if (the_low_target
.get_pc
== NULL
)
824 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
826 /* breakpoint_at reads from the current thread. */
827 saved_thread
= current_thread
;
828 current_thread
= get_lwp_thread (lwp
);
830 #if USE_SIGTRAP_SIGINFO
831 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
832 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
834 if (siginfo
.si_signo
== SIGTRAP
)
836 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
837 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
839 /* The si_code is ambiguous on this arch -- check debug
841 if (!check_stopped_by_watchpoint (lwp
))
842 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
844 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
846 /* If we determine the LWP stopped for a SW breakpoint,
847 trust it. Particularly don't check watchpoint
848 registers, because at least on s390, we'd find
849 stopped-by-watchpoint as long as there's a watchpoint
851 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
853 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
855 /* This can indicate either a hardware breakpoint or
856 hardware watchpoint. Check debug registers. */
857 if (!check_stopped_by_watchpoint (lwp
))
858 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
860 else if (siginfo
.si_code
== TRAP_TRACE
)
862 /* We may have single stepped an instruction that
863 triggered a watchpoint. In that case, on some
864 architectures (such as x86), instead of TRAP_HWBKPT,
865 si_code indicates TRAP_TRACE, and we need to check
866 the debug registers separately. */
867 if (!check_stopped_by_watchpoint (lwp
))
868 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
873 /* We may have just stepped a breakpoint instruction. E.g., in
874 non-stop mode, GDB first tells the thread A to step a range, and
875 then the user inserts a breakpoint inside the range. In that
876 case we need to report the breakpoint PC. */
877 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
878 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
879 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
881 if (hardware_breakpoint_inserted_here (pc
))
882 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
884 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
885 check_stopped_by_watchpoint (lwp
);
888 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
892 struct thread_info
*thr
= get_lwp_thread (lwp
);
894 debug_printf ("CSBB: %s stopped by software breakpoint\n",
895 target_pid_to_str (ptid_of (thr
)));
898 /* Back up the PC if necessary. */
899 if (pc
!= sw_breakpoint_pc
)
901 struct regcache
*regcache
902 = get_thread_regcache (current_thread
, 1);
903 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
906 /* Update this so we record the correct stop PC below. */
907 pc
= sw_breakpoint_pc
;
909 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
913 struct thread_info
*thr
= get_lwp_thread (lwp
);
915 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
916 target_pid_to_str (ptid_of (thr
)));
919 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
923 struct thread_info
*thr
= get_lwp_thread (lwp
);
925 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
926 target_pid_to_str (ptid_of (thr
)));
929 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
933 struct thread_info
*thr
= get_lwp_thread (lwp
);
935 debug_printf ("CSBB: %s stopped by trace\n",
936 target_pid_to_str (ptid_of (thr
)));
941 current_thread
= saved_thread
;
945 static struct lwp_info
*
946 add_lwp (ptid_t ptid
)
948 struct lwp_info
*lwp
;
950 lwp
= XCNEW (struct lwp_info
);
952 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
954 lwp
->thread
= add_thread (ptid
, lwp
);
956 if (the_low_target
.new_thread
!= NULL
)
957 the_low_target
.new_thread (lwp
);
962 /* Callback to be used when calling fork_inferior, responsible for
963 actually initiating the tracing of the inferior. */
968 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
969 (PTRACE_TYPE_ARG4
) 0) < 0)
970 trace_start_error_with_name ("ptrace");
972 if (setpgid (0, 0) < 0)
973 trace_start_error_with_name ("setpgid");
975 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
976 stdout to stderr so that inferior i/o doesn't corrupt the connection.
977 Also, redirect stdin to /dev/null. */
978 if (remote_connection_is_stdio ())
981 trace_start_error_with_name ("close");
982 if (open ("/dev/null", O_RDONLY
) < 0)
983 trace_start_error_with_name ("open");
985 trace_start_error_with_name ("dup2");
986 if (write (2, "stdin/stdout redirected\n",
987 sizeof ("stdin/stdout redirected\n") - 1) < 0)
989 /* Errors ignored. */;
994 /* Start an inferior process and returns its pid.
995 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
996 are its arguments. */
999 linux_create_inferior (const char *program
,
1000 const std::vector
<char *> &program_args
)
1002 client_state
&cs
= get_client_state ();
1003 struct lwp_info
*new_lwp
;
1008 maybe_disable_address_space_randomization restore_personality
1009 (cs
.disable_randomization
);
1010 std::string str_program_args
= stringify_argv (program_args
);
1012 pid
= fork_inferior (program
,
1013 str_program_args
.c_str (),
1014 get_environ ()->envp (), linux_ptrace_fun
,
1015 NULL
, NULL
, NULL
, NULL
);
1018 linux_add_process (pid
, 0);
1020 ptid
= ptid_t (pid
, pid
, 0);
1021 new_lwp
= add_lwp (ptid
);
1022 new_lwp
->must_set_ptrace_flags
= 1;
1024 post_fork_inferior (pid
, program
);
1029 /* Implement the post_create_inferior target_ops method. */
1032 linux_post_create_inferior (void)
1034 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1036 linux_arch_setup ();
1038 if (lwp
->must_set_ptrace_flags
)
1040 struct process_info
*proc
= current_process ();
1041 int options
= linux_low_ptrace_options (proc
->attached
);
1043 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1044 lwp
->must_set_ptrace_flags
= 0;
1048 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1052 linux_attach_lwp (ptid_t ptid
)
1054 struct lwp_info
*new_lwp
;
1055 int lwpid
= ptid
.lwp ();
1057 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1061 new_lwp
= add_lwp (ptid
);
1063 /* We need to wait for SIGSTOP before being able to make the next
1064 ptrace call on this LWP. */
1065 new_lwp
->must_set_ptrace_flags
= 1;
1067 if (linux_proc_pid_is_stopped (lwpid
))
1070 debug_printf ("Attached to a stopped process\n");
1072 /* The process is definitely stopped. It is in a job control
1073 stop, unless the kernel predates the TASK_STOPPED /
1074 TASK_TRACED distinction, in which case it might be in a
1075 ptrace stop. Make sure it is in a ptrace stop; from there we
1076 can kill it, signal it, et cetera.
1078 First make sure there is a pending SIGSTOP. Since we are
1079 already attached, the process can not transition from stopped
1080 to running without a PTRACE_CONT; so we know this signal will
1081 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1082 probably already in the queue (unless this kernel is old
1083 enough to use TASK_STOPPED for ptrace stops); but since
1084 SIGSTOP is not an RT signal, it can only be queued once. */
1085 kill_lwp (lwpid
, SIGSTOP
);
1087 /* Finally, resume the stopped process. This will deliver the
1088 SIGSTOP (or a higher priority signal, just like normal
1089 PTRACE_ATTACH), which we'll catch later on. */
1090 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1093 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1094 brings it to a halt.
1096 There are several cases to consider here:
1098 1) gdbserver has already attached to the process and is being notified
1099 of a new thread that is being created.
1100 In this case we should ignore that SIGSTOP and resume the
1101 process. This is handled below by setting stop_expected = 1,
1102 and the fact that add_thread sets last_resume_kind ==
1105 2) This is the first thread (the process thread), and we're attaching
1106 to it via attach_inferior.
1107 In this case we want the process thread to stop.
1108 This is handled by having linux_attach set last_resume_kind ==
1109 resume_stop after we return.
1111 If the pid we are attaching to is also the tgid, we attach to and
1112 stop all the existing threads. Otherwise, we attach to pid and
1113 ignore any other threads in the same group as this pid.
1115 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1117 In this case we want the thread to stop.
1118 FIXME: This case is currently not properly handled.
1119 We should wait for the SIGSTOP but don't. Things work apparently
1120 because enough time passes between when we ptrace (ATTACH) and when
1121 gdb makes the next ptrace call on the thread.
1123 On the other hand, if we are currently trying to stop all threads, we
1124 should treat the new thread as if we had sent it a SIGSTOP. This works
1125 because we are guaranteed that the add_lwp call above added us to the
1126 end of the list, and so the new thread has not yet reached
1127 wait_for_sigstop (but will). */
1128 new_lwp
->stop_expected
= 1;
1133 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1134 already attached. Returns true if a new LWP is found, false
1138 attach_proc_task_lwp_callback (ptid_t ptid
)
1140 /* Is this a new thread? */
1141 if (find_thread_ptid (ptid
) == NULL
)
1143 int lwpid
= ptid
.lwp ();
1147 debug_printf ("Found new lwp %d\n", lwpid
);
1149 err
= linux_attach_lwp (ptid
);
1151 /* Be quiet if we simply raced with the thread exiting. EPERM
1152 is returned if the thread's task still exists, and is marked
1153 as exited or zombie, as well as other conditions, so in that
1154 case, confirm the status in /proc/PID/status. */
1156 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1160 debug_printf ("Cannot attach to lwp %d: "
1161 "thread is gone (%d: %s)\n",
1162 lwpid
, err
, strerror (err
));
1168 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1170 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1178 static void async_file_mark (void);
1180 /* Attach to PID. If PID is the tgid, attach to it and all
1184 linux_attach (unsigned long pid
)
1186 struct process_info
*proc
;
1187 struct thread_info
*initial_thread
;
1188 ptid_t ptid
= ptid_t (pid
, pid
, 0);
1191 /* Attach to PID. We will check for other threads
1193 err
= linux_attach_lwp (ptid
);
1196 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1198 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1201 proc
= linux_add_process (pid
, 1);
1203 /* Don't ignore the initial SIGSTOP if we just attached to this
1204 process. It will be collected by wait shortly. */
1205 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
, 0));
1206 initial_thread
->last_resume_kind
= resume_stop
;
1208 /* We must attach to every LWP. If /proc is mounted, use that to
1209 find them now. On the one hand, the inferior may be using raw
1210 clone instead of using pthreads. On the other hand, even if it
1211 is using pthreads, GDB may not be connected yet (thread_db needs
1212 to do symbol lookups, through qSymbol). Also, thread_db walks
1213 structures in the inferior's address space to find the list of
1214 threads/LWPs, and those structures may well be corrupted. Note
1215 that once thread_db is loaded, we'll still use it to list threads
1216 and associate pthread info with each LWP. */
1217 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1219 /* GDB will shortly read the xml target description for this
1220 process, to figure out the process' architecture. But the target
1221 description is only filled in when the first process/thread in
1222 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1223 that now, otherwise, if GDB is fast enough, it could read the
1224 target description _before_ that initial stop. */
1227 struct lwp_info
*lwp
;
1229 ptid_t pid_ptid
= ptid_t (pid
);
1231 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1233 gdb_assert (lwpid
> 0);
1235 lwp
= find_lwp_pid (ptid_t (lwpid
));
1237 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1239 lwp
->status_pending_p
= 1;
1240 lwp
->status_pending
= wstat
;
1243 initial_thread
->last_resume_kind
= resume_continue
;
1247 gdb_assert (proc
->tdesc
!= NULL
);
1254 last_thread_of_process_p (int pid
)
1256 bool seen_one
= false;
1258 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1262 /* This is the first thread of this process we see. */
1268 /* This is the second thread of this process we see. */
1273 return thread
== NULL
;
1279 linux_kill_one_lwp (struct lwp_info
*lwp
)
1281 struct thread_info
*thr
= get_lwp_thread (lwp
);
1282 int pid
= lwpid_of (thr
);
1284 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1285 there is no signal context, and ptrace(PTRACE_KILL) (or
1286 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1287 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1288 alternative is to kill with SIGKILL. We only need one SIGKILL
1289 per process, not one for each thread. But since we still support
1290 support debugging programs using raw clone without CLONE_THREAD,
1291 we send one for each thread. For years, we used PTRACE_KILL
1292 only, so we're being a bit paranoid about some old kernels where
1293 PTRACE_KILL might work better (dubious if there are any such, but
1294 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1295 second, and so we're fine everywhere. */
1298 kill_lwp (pid
, SIGKILL
);
1301 int save_errno
= errno
;
1303 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1304 target_pid_to_str (ptid_of (thr
)),
1305 save_errno
? strerror (save_errno
) : "OK");
1309 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1312 int save_errno
= errno
;
1314 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1315 target_pid_to_str (ptid_of (thr
)),
1316 save_errno
? strerror (save_errno
) : "OK");
1320 /* Kill LWP and wait for it to die. */
1323 kill_wait_lwp (struct lwp_info
*lwp
)
1325 struct thread_info
*thr
= get_lwp_thread (lwp
);
1326 int pid
= ptid_of (thr
).pid ();
1327 int lwpid
= ptid_of (thr
).lwp ();
1332 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1336 linux_kill_one_lwp (lwp
);
1338 /* Make sure it died. Notes:
1340 - The loop is most likely unnecessary.
1342 - We don't use linux_wait_for_event as that could delete lwps
1343 while we're iterating over them. We're not interested in
1344 any pending status at this point, only in making sure all
1345 wait status on the kernel side are collected until the
1348 - We don't use __WALL here as the __WALL emulation relies on
1349 SIGCHLD, and killing a stopped process doesn't generate
1350 one, nor an exit status.
1352 res
= my_waitpid (lwpid
, &wstat
, 0);
1353 if (res
== -1 && errno
== ECHILD
)
1354 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1355 } while (res
> 0 && WIFSTOPPED (wstat
));
1357 /* Even if it was stopped, the child may have already disappeared.
1358 E.g., if it was killed by SIGKILL. */
1359 if (res
< 0 && errno
!= ECHILD
)
1360 perror_with_name ("kill_wait_lwp");
1363 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1364 except the leader. */
1367 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1369 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1371 /* We avoid killing the first thread here, because of a Linux kernel (at
1372 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1373 the children get a chance to be reaped, it will remain a zombie
1376 if (lwpid_of (thread
) == pid
)
1379 debug_printf ("lkop: is last of process %s\n",
1380 target_pid_to_str (thread
->id
));
1384 kill_wait_lwp (lwp
);
1388 linux_kill (process_info
*process
)
1390 int pid
= process
->pid
;
1392 /* If we're killing a running inferior, make sure it is stopped
1393 first, as PTRACE_KILL will not work otherwise. */
1394 stop_all_lwps (0, NULL
);
1396 for_each_thread (pid
, [&] (thread_info
*thread
)
1398 kill_one_lwp_callback (thread
, pid
);
1401 /* See the comment in linux_kill_one_lwp. We did not kill the first
1402 thread in the list, so do so now. */
1403 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1408 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1412 kill_wait_lwp (lwp
);
1414 the_target
->mourn (process
);
1416 /* Since we presently can only stop all lwps of all processes, we
1417 need to unstop lwps of other processes. */
1418 unstop_all_lwps (0, NULL
);
1422 /* Get pending signal of THREAD, for detaching purposes. This is the
1423 signal the thread last stopped for, which we need to deliver to the
1424 thread when detaching, otherwise, it'd be suppressed/lost. */
1427 get_detach_signal (struct thread_info
*thread
)
1429 client_state
&cs
= get_client_state ();
1430 enum gdb_signal signo
= GDB_SIGNAL_0
;
1432 struct lwp_info
*lp
= get_thread_lwp (thread
);
1434 if (lp
->status_pending_p
)
1435 status
= lp
->status_pending
;
1438 /* If the thread had been suspended by gdbserver, and it stopped
1439 cleanly, then it'll have stopped with SIGSTOP. But we don't
1440 want to deliver that SIGSTOP. */
1441 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1442 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1445 /* Otherwise, we may need to deliver the signal we
1447 status
= lp
->last_status
;
1450 if (!WIFSTOPPED (status
))
1453 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1454 target_pid_to_str (ptid_of (thread
)));
1458 /* Extended wait statuses aren't real SIGTRAPs. */
1459 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1462 debug_printf ("GPS: lwp %s had stopped with extended "
1463 "status: no pending signal\n",
1464 target_pid_to_str (ptid_of (thread
)));
1468 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1470 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1473 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1474 target_pid_to_str (ptid_of (thread
)),
1475 gdb_signal_to_string (signo
));
1478 else if (!cs
.program_signals_p
1479 /* If we have no way to know which signals GDB does not
1480 want to have passed to the program, assume
1481 SIGTRAP/SIGINT, which is GDB's default. */
1482 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1485 debug_printf ("GPS: lwp %s had signal %s, "
1486 "but we don't know if we should pass it. "
1487 "Default to not.\n",
1488 target_pid_to_str (ptid_of (thread
)),
1489 gdb_signal_to_string (signo
));
1495 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1496 target_pid_to_str (ptid_of (thread
)),
1497 gdb_signal_to_string (signo
));
1499 return WSTOPSIG (status
);
1503 /* Detach from LWP. */
1506 linux_detach_one_lwp (struct lwp_info
*lwp
)
1508 struct thread_info
*thread
= get_lwp_thread (lwp
);
1512 /* If there is a pending SIGSTOP, get rid of it. */
1513 if (lwp
->stop_expected
)
1516 debug_printf ("Sending SIGCONT to %s\n",
1517 target_pid_to_str (ptid_of (thread
)));
1519 kill_lwp (lwpid_of (thread
), SIGCONT
);
1520 lwp
->stop_expected
= 0;
1523 /* Pass on any pending signal for this thread. */
1524 sig
= get_detach_signal (thread
);
1526 /* Preparing to resume may try to write registers, and fail if the
1527 lwp is zombie. If that happens, ignore the error. We'll handle
1528 it below, when detach fails with ESRCH. */
1531 /* Flush any pending changes to the process's registers. */
1532 regcache_invalidate_thread (thread
);
1534 /* Finally, let it resume. */
1535 if (the_low_target
.prepare_to_resume
!= NULL
)
1536 the_low_target
.prepare_to_resume (lwp
);
1538 CATCH (ex
, RETURN_MASK_ERROR
)
1540 if (!check_ptrace_stopped_lwp_gone (lwp
))
1541 throw_exception (ex
);
1545 lwpid
= lwpid_of (thread
);
1546 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1547 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1549 int save_errno
= errno
;
1551 /* We know the thread exists, so ESRCH must mean the lwp is
1552 zombie. This can happen if one of the already-detached
1553 threads exits the whole thread group. In that case we're
1554 still attached, and must reap the lwp. */
1555 if (save_errno
== ESRCH
)
1559 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1562 warning (_("Couldn't reap LWP %d while detaching: %s"),
1563 lwpid
, strerror (errno
));
1565 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1567 warning (_("Reaping LWP %d while detaching "
1568 "returned unexpected status 0x%x"),
1574 error (_("Can't detach %s: %s"),
1575 target_pid_to_str (ptid_of (thread
)),
1576 strerror (save_errno
));
1579 else if (debug_threads
)
1581 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1582 target_pid_to_str (ptid_of (thread
)),
1589 /* Callback for for_each_thread. Detaches from non-leader threads of a
1593 linux_detach_lwp_callback (thread_info
*thread
)
1595 /* We don't actually detach from the thread group leader just yet.
1596 If the thread group exits, we must reap the zombie clone lwps
1597 before we're able to reap the leader. */
1598 if (thread
->id
.pid () == thread
->id
.lwp ())
1601 lwp_info
*lwp
= get_thread_lwp (thread
);
1602 linux_detach_one_lwp (lwp
);
1606 linux_detach (process_info
*process
)
1608 struct lwp_info
*main_lwp
;
1610 /* As there's a step over already in progress, let it finish first,
1611 otherwise nesting a stabilize_threads operation on top gets real
1613 complete_ongoing_step_over ();
1615 /* Stop all threads before detaching. First, ptrace requires that
1616 the thread is stopped to sucessfully detach. Second, thread_db
1617 may need to uninstall thread event breakpoints from memory, which
1618 only works with a stopped process anyway. */
1619 stop_all_lwps (0, NULL
);
1621 #ifdef USE_THREAD_DB
1622 thread_db_detach (process
);
1625 /* Stabilize threads (move out of jump pads). */
1626 stabilize_threads ();
1628 /* Detach from the clone lwps first. If the thread group exits just
1629 while we're detaching, we must reap the clone lwps before we're
1630 able to reap the leader. */
1631 for_each_thread (process
->pid
, linux_detach_lwp_callback
);
1633 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1634 linux_detach_one_lwp (main_lwp
);
1636 the_target
->mourn (process
);
1638 /* Since we presently can only stop all lwps of all processes, we
1639 need to unstop lwps of other processes. */
1640 unstop_all_lwps (0, NULL
);
1644 /* Remove all LWPs that belong to process PROC from the lwp list. */
1647 linux_mourn (struct process_info
*process
)
1649 struct process_info_private
*priv
;
1651 #ifdef USE_THREAD_DB
1652 thread_db_mourn (process
);
1655 for_each_thread (process
->pid
, [] (thread_info
*thread
)
1657 delete_lwp (get_thread_lwp (thread
));
1660 /* Freeing all private data. */
1661 priv
= process
->priv
;
1662 if (the_low_target
.delete_process
!= NULL
)
1663 the_low_target
.delete_process (priv
->arch_private
);
1665 gdb_assert (priv
->arch_private
== NULL
);
1667 process
->priv
= NULL
;
1669 remove_process (process
);
1673 linux_join (int pid
)
1678 ret
= my_waitpid (pid
, &status
, 0);
1679 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1681 } while (ret
!= -1 || errno
!= ECHILD
);
1684 /* Return nonzero if the given thread is still alive. */
1686 linux_thread_alive (ptid_t ptid
)
1688 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1690 /* We assume we always know if a thread exits. If a whole process
1691 exited but we still haven't been able to report it to GDB, we'll
1692 hold on to the last lwp of the dead process. */
1694 return !lwp_is_marked_dead (lwp
);
1699 /* Return 1 if this lwp still has an interesting status pending. If
1700 not (e.g., it had stopped for a breakpoint that is gone), return
1704 thread_still_has_status_pending_p (struct thread_info
*thread
)
1706 struct lwp_info
*lp
= get_thread_lwp (thread
);
1708 if (!lp
->status_pending_p
)
1711 if (thread
->last_resume_kind
!= resume_stop
1712 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1713 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1715 struct thread_info
*saved_thread
;
1719 gdb_assert (lp
->last_status
!= 0);
1723 saved_thread
= current_thread
;
1724 current_thread
= thread
;
1726 if (pc
!= lp
->stop_pc
)
1729 debug_printf ("PC of %ld changed\n",
1734 #if !USE_SIGTRAP_SIGINFO
1735 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1736 && !(*the_low_target
.breakpoint_at
) (pc
))
1739 debug_printf ("previous SW breakpoint of %ld gone\n",
1743 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1744 && !hardware_breakpoint_inserted_here (pc
))
1747 debug_printf ("previous HW breakpoint of %ld gone\n",
1753 current_thread
= saved_thread
;
1758 debug_printf ("discarding pending breakpoint status\n");
1759 lp
->status_pending_p
= 0;
1767 /* Returns true if LWP is resumed from the client's perspective. */
1770 lwp_resumed (struct lwp_info
*lwp
)
1772 struct thread_info
*thread
= get_lwp_thread (lwp
);
1774 if (thread
->last_resume_kind
!= resume_stop
)
1777 /* Did gdb send us a `vCont;t', but we haven't reported the
1778 corresponding stop to gdb yet? If so, the thread is still
1779 resumed/running from gdb's perspective. */
1780 if (thread
->last_resume_kind
== resume_stop
1781 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1787 /* Return true if this lwp has an interesting status pending. */
1789 status_pending_p_callback (thread_info
*thread
, ptid_t ptid
)
1791 struct lwp_info
*lp
= get_thread_lwp (thread
);
1793 /* Check if we're only interested in events from a specific process
1794 or a specific LWP. */
1795 if (!thread
->id
.matches (ptid
))
1798 if (!lwp_resumed (lp
))
1801 if (lp
->status_pending_p
1802 && !thread_still_has_status_pending_p (thread
))
1804 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1808 return lp
->status_pending_p
;
1812 find_lwp_pid (ptid_t ptid
)
1814 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1816 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1817 return thr_arg
->id
.lwp () == lwp
;
1823 return get_thread_lwp (thread
);
1826 /* Return the number of known LWPs in the tgid given by PID. */
1833 for_each_thread (pid
, [&] (thread_info
*thread
)
1841 /* See nat/linux-nat.h. */
1844 iterate_over_lwps (ptid_t filter
,
1845 iterate_over_lwps_ftype callback
,
1848 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1850 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1852 return callback (lwp
, data
);
1858 return get_thread_lwp (thread
);
1861 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1862 their exits until all other threads in the group have exited. */
1865 check_zombie_leaders (void)
1867 for_each_process ([] (process_info
*proc
) {
1868 pid_t leader_pid
= pid_of (proc
);
1869 struct lwp_info
*leader_lp
;
1871 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1874 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1875 "num_lwps=%d, zombie=%d\n",
1876 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1877 linux_proc_pid_is_zombie (leader_pid
));
1879 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1880 /* Check if there are other threads in the group, as we may
1881 have raced with the inferior simply exiting. */
1882 && !last_thread_of_process_p (leader_pid
)
1883 && linux_proc_pid_is_zombie (leader_pid
))
1885 /* A leader zombie can mean one of two things:
1887 - It exited, and there's an exit status pending
1888 available, or only the leader exited (not the whole
1889 program). In the latter case, we can't waitpid the
1890 leader's exit status until all other threads are gone.
1892 - There are 3 or more threads in the group, and a thread
1893 other than the leader exec'd. On an exec, the Linux
1894 kernel destroys all other threads (except the execing
1895 one) in the thread group, and resets the execing thread's
1896 tid to the tgid. No exit notification is sent for the
1897 execing thread -- from the ptracer's perspective, it
1898 appears as though the execing thread just vanishes.
1899 Until we reap all other threads except the leader and the
1900 execing thread, the leader will be zombie, and the
1901 execing thread will be in `D (disc sleep)'. As soon as
1902 all other threads are reaped, the execing thread changes
1903 it's tid to the tgid, and the previous (zombie) leader
1904 vanishes, giving place to the "new" leader. We could try
1905 distinguishing the exit and exec cases, by waiting once
1906 more, and seeing if something comes out, but it doesn't
1907 sound useful. The previous leader _does_ go away, and
1908 we'll re-add the new one once we see the exec event
1909 (which is just the same as what would happen if the
1910 previous leader did exit voluntarily before some other
1914 debug_printf ("CZL: Thread group leader %d zombie "
1915 "(it exited, or another thread execd).\n",
1918 delete_lwp (leader_lp
);
1923 /* Callback for `find_thread'. Returns the first LWP that is not
1927 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1929 if (!thread
->id
.matches (filter
))
1932 lwp_info
*lwp
= get_thread_lwp (thread
);
1934 return !lwp
->stopped
;
1937 /* Increment LWP's suspend count. */
1940 lwp_suspended_inc (struct lwp_info
*lwp
)
1944 if (debug_threads
&& lwp
->suspended
> 4)
1946 struct thread_info
*thread
= get_lwp_thread (lwp
);
1948 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1949 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1953 /* Decrement LWP's suspend count. */
1956 lwp_suspended_decr (struct lwp_info
*lwp
)
1960 if (lwp
->suspended
< 0)
1962 struct thread_info
*thread
= get_lwp_thread (lwp
);
1964 internal_error (__FILE__
, __LINE__
,
1965 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1970 /* This function should only be called if the LWP got a SIGTRAP.
1972 Handle any tracepoint steps or hits. Return true if a tracepoint
1973 event was handled, 0 otherwise. */
1976 handle_tracepoints (struct lwp_info
*lwp
)
1978 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1979 int tpoint_related_event
= 0;
1981 gdb_assert (lwp
->suspended
== 0);
1983 /* If this tracepoint hit causes a tracing stop, we'll immediately
1984 uninsert tracepoints. To do this, we temporarily pause all
1985 threads, unpatch away, and then unpause threads. We need to make
1986 sure the unpausing doesn't resume LWP too. */
1987 lwp_suspended_inc (lwp
);
1989 /* And we need to be sure that any all-threads-stopping doesn't try
1990 to move threads out of the jump pads, as it could deadlock the
1991 inferior (LWP could be in the jump pad, maybe even holding the
1994 /* Do any necessary step collect actions. */
1995 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1997 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1999 /* See if we just hit a tracepoint and do its main collect
2001 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
2003 lwp_suspended_decr (lwp
);
2005 gdb_assert (lwp
->suspended
== 0);
2006 gdb_assert (!stabilizing_threads
2007 || (lwp
->collecting_fast_tracepoint
2008 != fast_tpoint_collect_result::not_collecting
));
2010 if (tpoint_related_event
)
2013 debug_printf ("got a tracepoint event\n");
2020 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2021 collection status. */
2023 static fast_tpoint_collect_result
2024 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
2025 struct fast_tpoint_collect_status
*status
)
2027 CORE_ADDR thread_area
;
2028 struct thread_info
*thread
= get_lwp_thread (lwp
);
2030 if (the_low_target
.get_thread_area
== NULL
)
2031 return fast_tpoint_collect_result::not_collecting
;
2033 /* Get the thread area address. This is used to recognize which
2034 thread is which when tracing with the in-process agent library.
2035 We don't read anything from the address, and treat it as opaque;
2036 it's the address itself that we assume is unique per-thread. */
2037 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
2038 return fast_tpoint_collect_result::not_collecting
;
2040 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
2043 /* The reason we resume in the caller, is because we want to be able
2044 to pass lwp->status_pending as WSTAT, and we need to clear
2045 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2046 refuses to resume. */
2049 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
2051 struct thread_info
*saved_thread
;
2053 saved_thread
= current_thread
;
2054 current_thread
= get_lwp_thread (lwp
);
2057 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
2058 && supports_fast_tracepoints ()
2059 && agent_loaded_p ())
2061 struct fast_tpoint_collect_status status
;
2064 debug_printf ("Checking whether LWP %ld needs to move out of the "
2066 lwpid_of (current_thread
));
2068 fast_tpoint_collect_result r
2069 = linux_fast_tracepoint_collecting (lwp
, &status
);
2072 || (WSTOPSIG (*wstat
) != SIGILL
2073 && WSTOPSIG (*wstat
) != SIGFPE
2074 && WSTOPSIG (*wstat
) != SIGSEGV
2075 && WSTOPSIG (*wstat
) != SIGBUS
))
2077 lwp
->collecting_fast_tracepoint
= r
;
2079 if (r
!= fast_tpoint_collect_result::not_collecting
)
2081 if (r
== fast_tpoint_collect_result::before_insn
2082 && lwp
->exit_jump_pad_bkpt
== NULL
)
2084 /* Haven't executed the original instruction yet.
2085 Set breakpoint there, and wait till it's hit,
2086 then single-step until exiting the jump pad. */
2087 lwp
->exit_jump_pad_bkpt
2088 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2092 debug_printf ("Checking whether LWP %ld needs to move out of "
2093 "the jump pad...it does\n",
2094 lwpid_of (current_thread
));
2095 current_thread
= saved_thread
;
2102 /* If we get a synchronous signal while collecting, *and*
2103 while executing the (relocated) original instruction,
2104 reset the PC to point at the tpoint address, before
2105 reporting to GDB. Otherwise, it's an IPA lib bug: just
2106 report the signal to GDB, and pray for the best. */
2108 lwp
->collecting_fast_tracepoint
2109 = fast_tpoint_collect_result::not_collecting
;
2111 if (r
!= fast_tpoint_collect_result::not_collecting
2112 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2113 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2116 struct regcache
*regcache
;
2118 /* The si_addr on a few signals references the address
2119 of the faulting instruction. Adjust that as
2121 if ((WSTOPSIG (*wstat
) == SIGILL
2122 || WSTOPSIG (*wstat
) == SIGFPE
2123 || WSTOPSIG (*wstat
) == SIGBUS
2124 || WSTOPSIG (*wstat
) == SIGSEGV
)
2125 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2126 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2127 /* Final check just to make sure we don't clobber
2128 the siginfo of non-kernel-sent signals. */
2129 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2131 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2132 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2133 (PTRACE_TYPE_ARG3
) 0, &info
);
2136 regcache
= get_thread_regcache (current_thread
, 1);
2137 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2138 lwp
->stop_pc
= status
.tpoint_addr
;
2140 /* Cancel any fast tracepoint lock this thread was
2142 force_unlock_trace_buffer ();
2145 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2148 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2149 "stopping all threads momentarily.\n");
2151 stop_all_lwps (1, lwp
);
2153 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2154 lwp
->exit_jump_pad_bkpt
= NULL
;
2156 unstop_all_lwps (1, lwp
);
2158 gdb_assert (lwp
->suspended
>= 0);
2164 debug_printf ("Checking whether LWP %ld needs to move out of the "
2166 lwpid_of (current_thread
));
2168 current_thread
= saved_thread
;
2172 /* Enqueue one signal in the "signals to report later when out of the
2176 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2178 struct pending_signals
*p_sig
;
2179 struct thread_info
*thread
= get_lwp_thread (lwp
);
2182 debug_printf ("Deferring signal %d for LWP %ld.\n",
2183 WSTOPSIG (*wstat
), lwpid_of (thread
));
2187 struct pending_signals
*sig
;
2189 for (sig
= lwp
->pending_signals_to_report
;
2192 debug_printf (" Already queued %d\n",
2195 debug_printf (" (no more currently queued signals)\n");
2198 /* Don't enqueue non-RT signals if they are already in the deferred
2199 queue. (SIGSTOP being the easiest signal to see ending up here
2201 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2203 struct pending_signals
*sig
;
2205 for (sig
= lwp
->pending_signals_to_report
;
2209 if (sig
->signal
== WSTOPSIG (*wstat
))
2212 debug_printf ("Not requeuing already queued non-RT signal %d"
2221 p_sig
= XCNEW (struct pending_signals
);
2222 p_sig
->prev
= lwp
->pending_signals_to_report
;
2223 p_sig
->signal
= WSTOPSIG (*wstat
);
2225 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2228 lwp
->pending_signals_to_report
= p_sig
;
2231 /* Dequeue one signal from the "signals to report later when out of
2232 the jump pad" list. */
2235 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2237 struct thread_info
*thread
= get_lwp_thread (lwp
);
2239 if (lwp
->pending_signals_to_report
!= NULL
)
2241 struct pending_signals
**p_sig
;
2243 p_sig
= &lwp
->pending_signals_to_report
;
2244 while ((*p_sig
)->prev
!= NULL
)
2245 p_sig
= &(*p_sig
)->prev
;
2247 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2248 if ((*p_sig
)->info
.si_signo
!= 0)
2249 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2255 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2256 WSTOPSIG (*wstat
), lwpid_of (thread
));
2260 struct pending_signals
*sig
;
2262 for (sig
= lwp
->pending_signals_to_report
;
2265 debug_printf (" Still queued %d\n",
2268 debug_printf (" (no more queued signals)\n");
2277 /* Fetch the possibly triggered data watchpoint info and store it in
2280 On some archs, like x86, that use debug registers to set
2281 watchpoints, it's possible that the way to know which watched
2282 address trapped, is to check the register that is used to select
2283 which address to watch. Problem is, between setting the watchpoint
2284 and reading back which data address trapped, the user may change
2285 the set of watchpoints, and, as a consequence, GDB changes the
2286 debug registers in the inferior. To avoid reading back a stale
2287 stopped-data-address when that happens, we cache in LP the fact
2288 that a watchpoint trapped, and the corresponding data address, as
2289 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2290 registers meanwhile, we have the cached data we can rely on. */
2293 check_stopped_by_watchpoint (struct lwp_info
*child
)
2295 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2297 struct thread_info
*saved_thread
;
2299 saved_thread
= current_thread
;
2300 current_thread
= get_lwp_thread (child
);
2302 if (the_low_target
.stopped_by_watchpoint ())
2304 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2306 if (the_low_target
.stopped_data_address
!= NULL
)
2307 child
->stopped_data_address
2308 = the_low_target
.stopped_data_address ();
2310 child
->stopped_data_address
= 0;
2313 current_thread
= saved_thread
;
2316 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2319 /* Return the ptrace options that we want to try to enable. */
2322 linux_low_ptrace_options (int attached
)
2324 client_state
&cs
= get_client_state ();
2328 options
|= PTRACE_O_EXITKILL
;
2330 if (cs
.report_fork_events
)
2331 options
|= PTRACE_O_TRACEFORK
;
2333 if (cs
.report_vfork_events
)
2334 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2336 if (cs
.report_exec_events
)
2337 options
|= PTRACE_O_TRACEEXEC
;
2339 options
|= PTRACE_O_TRACESYSGOOD
;
2344 /* Do low-level handling of the event, and check if we should go on
2345 and pass it to caller code. Return the affected lwp if we are, or
2348 static struct lwp_info
*
2349 linux_low_filter_event (int lwpid
, int wstat
)
2351 client_state
&cs
= get_client_state ();
2352 struct lwp_info
*child
;
2353 struct thread_info
*thread
;
2354 int have_stop_pc
= 0;
2356 child
= find_lwp_pid (ptid_t (lwpid
));
2358 /* Check for stop events reported by a process we didn't already
2359 know about - anything not already in our LWP list.
2361 If we're expecting to receive stopped processes after
2362 fork, vfork, and clone events, then we'll just add the
2363 new one to our list and go back to waiting for the event
2364 to be reported - the stopped process might be returned
2365 from waitpid before or after the event is.
2367 But note the case of a non-leader thread exec'ing after the
2368 leader having exited, and gone from our lists (because
2369 check_zombie_leaders deleted it). The non-leader thread
2370 changes its tid to the tgid. */
2372 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2373 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2377 /* A multi-thread exec after we had seen the leader exiting. */
2380 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2381 "after exec.\n", lwpid
);
2384 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2385 child
= add_lwp (child_ptid
);
2387 current_thread
= child
->thread
;
2390 /* If we didn't find a process, one of two things presumably happened:
2391 - A process we started and then detached from has exited. Ignore it.
2392 - A process we are controlling has forked and the new child's stop
2393 was reported to us by the kernel. Save its PID. */
2394 if (child
== NULL
&& WIFSTOPPED (wstat
))
2396 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2399 else if (child
== NULL
)
2402 thread
= get_lwp_thread (child
);
2406 child
->last_status
= wstat
;
2408 /* Check if the thread has exited. */
2409 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2412 debug_printf ("LLFE: %d exited.\n", lwpid
);
2414 if (finish_step_over (child
))
2416 /* Unsuspend all other LWPs, and set them back running again. */
2417 unsuspend_all_lwps (child
);
2420 /* If there is at least one more LWP, then the exit signal was
2421 not the end of the debugged application and should be
2422 ignored, unless GDB wants to hear about thread exits. */
2423 if (cs
.report_thread_events
2424 || last_thread_of_process_p (pid_of (thread
)))
2426 /* Since events are serialized to GDB core, and we can't
2427 report this one right now. Leave the status pending for
2428 the next time we're able to report it. */
2429 mark_lwp_dead (child
, wstat
);
2439 gdb_assert (WIFSTOPPED (wstat
));
2441 if (WIFSTOPPED (wstat
))
2443 struct process_info
*proc
;
2445 /* Architecture-specific setup after inferior is running. */
2446 proc
= find_process_pid (pid_of (thread
));
2447 if (proc
->tdesc
== NULL
)
2451 /* This needs to happen after we have attached to the
2452 inferior and it is stopped for the first time, but
2453 before we access any inferior registers. */
2454 linux_arch_setup_thread (thread
);
2458 /* The process is started, but GDBserver will do
2459 architecture-specific setup after the program stops at
2460 the first instruction. */
2461 child
->status_pending_p
= 1;
2462 child
->status_pending
= wstat
;
2468 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2470 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2471 int options
= linux_low_ptrace_options (proc
->attached
);
2473 linux_enable_event_reporting (lwpid
, options
);
2474 child
->must_set_ptrace_flags
= 0;
2477 /* Always update syscall_state, even if it will be filtered later. */
2478 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2480 child
->syscall_state
2481 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2482 ? TARGET_WAITKIND_SYSCALL_RETURN
2483 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2487 /* Almost all other ptrace-stops are known to be outside of system
2488 calls, with further exceptions in handle_extended_wait. */
2489 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2492 /* Be careful to not overwrite stop_pc until save_stop_reason is
2494 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2495 && linux_is_extended_waitstatus (wstat
))
2497 child
->stop_pc
= get_pc (child
);
2498 if (handle_extended_wait (&child
, wstat
))
2500 /* The event has been handled, so just return without
2506 if (linux_wstatus_maybe_breakpoint (wstat
))
2508 if (save_stop_reason (child
))
2513 child
->stop_pc
= get_pc (child
);
2515 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2516 && child
->stop_expected
)
2519 debug_printf ("Expected stop.\n");
2520 child
->stop_expected
= 0;
2522 if (thread
->last_resume_kind
== resume_stop
)
2524 /* We want to report the stop to the core. Treat the
2525 SIGSTOP as a normal event. */
2527 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2528 target_pid_to_str (ptid_of (thread
)));
2530 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2532 /* Stopping threads. We don't want this SIGSTOP to end up
2535 debug_printf ("LLW: SIGSTOP caught for %s "
2536 "while stopping threads.\n",
2537 target_pid_to_str (ptid_of (thread
)));
2542 /* This is a delayed SIGSTOP. Filter out the event. */
2544 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2545 child
->stepping
? "step" : "continue",
2546 target_pid_to_str (ptid_of (thread
)));
2548 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2553 child
->status_pending_p
= 1;
2554 child
->status_pending
= wstat
;
2558 /* Return true if THREAD is doing hardware single step. */
2561 maybe_hw_step (struct thread_info
*thread
)
2563 if (can_hardware_single_step ())
2567 /* GDBserver must insert single-step breakpoint for software
2569 gdb_assert (has_single_step_breakpoints (thread
));
2574 /* Resume LWPs that are currently stopped without any pending status
2575 to report, but are resumed from the core's perspective. */
2578 resume_stopped_resumed_lwps (thread_info
*thread
)
2580 struct lwp_info
*lp
= get_thread_lwp (thread
);
2584 && !lp
->status_pending_p
2585 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2589 if (thread
->last_resume_kind
== resume_step
)
2590 step
= maybe_hw_step (thread
);
2593 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2594 target_pid_to_str (ptid_of (thread
)),
2595 paddress (lp
->stop_pc
),
2598 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2602 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2603 match FILTER_PTID (leaving others pending). The PTIDs can be:
2604 minus_one_ptid, to specify any child; a pid PTID, specifying all
2605 lwps of a thread group; or a PTID representing a single lwp. Store
2606 the stop status through the status pointer WSTAT. OPTIONS is
2607 passed to the waitpid call. Return 0 if no event was found and
2608 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2609 was found. Return the PID of the stopped child otherwise. */
2612 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2613 int *wstatp
, int options
)
2615 struct thread_info
*event_thread
;
2616 struct lwp_info
*event_child
, *requested_child
;
2617 sigset_t block_mask
, prev_mask
;
2620 /* N.B. event_thread points to the thread_info struct that contains
2621 event_child. Keep them in sync. */
2622 event_thread
= NULL
;
2624 requested_child
= NULL
;
2626 /* Check for a lwp with a pending status. */
2628 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2630 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2632 return status_pending_p_callback (thread
, filter_ptid
);
2635 if (event_thread
!= NULL
)
2636 event_child
= get_thread_lwp (event_thread
);
2637 if (debug_threads
&& event_thread
)
2638 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2640 else if (filter_ptid
!= null_ptid
)
2642 requested_child
= find_lwp_pid (filter_ptid
);
2644 if (stopping_threads
== NOT_STOPPING_THREADS
2645 && requested_child
->status_pending_p
2646 && (requested_child
->collecting_fast_tracepoint
2647 != fast_tpoint_collect_result::not_collecting
))
2649 enqueue_one_deferred_signal (requested_child
,
2650 &requested_child
->status_pending
);
2651 requested_child
->status_pending_p
= 0;
2652 requested_child
->status_pending
= 0;
2653 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2656 if (requested_child
->suspended
2657 && requested_child
->status_pending_p
)
2659 internal_error (__FILE__
, __LINE__
,
2660 "requesting an event out of a"
2661 " suspended child?");
2664 if (requested_child
->status_pending_p
)
2666 event_child
= requested_child
;
2667 event_thread
= get_lwp_thread (event_child
);
2671 if (event_child
!= NULL
)
2674 debug_printf ("Got an event from pending child %ld (%04x)\n",
2675 lwpid_of (event_thread
), event_child
->status_pending
);
2676 *wstatp
= event_child
->status_pending
;
2677 event_child
->status_pending_p
= 0;
2678 event_child
->status_pending
= 0;
2679 current_thread
= event_thread
;
2680 return lwpid_of (event_thread
);
2683 /* But if we don't find a pending event, we'll have to wait.
2685 We only enter this loop if no process has a pending wait status.
2686 Thus any action taken in response to a wait status inside this
2687 loop is responding as soon as we detect the status, not after any
2690 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2691 all signals while here. */
2692 sigfillset (&block_mask
);
2693 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2695 /* Always pull all events out of the kernel. We'll randomly select
2696 an event LWP out of all that have events, to prevent
2698 while (event_child
== NULL
)
2702 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2705 - If the thread group leader exits while other threads in the
2706 thread group still exist, waitpid(TGID, ...) hangs. That
2707 waitpid won't return an exit status until the other threads
2708 in the group are reaped.
2710 - When a non-leader thread execs, that thread just vanishes
2711 without reporting an exit (so we'd hang if we waited for it
2712 explicitly in that case). The exec event is reported to
2715 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2718 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2719 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2725 debug_printf ("LLW: waitpid %ld received %s\n",
2726 (long) ret
, status_to_str (*wstatp
));
2729 /* Filter all events. IOW, leave all events pending. We'll
2730 randomly select an event LWP out of all that have events
2732 linux_low_filter_event (ret
, *wstatp
);
2733 /* Retry until nothing comes out of waitpid. A single
2734 SIGCHLD can indicate more than one child stopped. */
2738 /* Now that we've pulled all events out of the kernel, resume
2739 LWPs that don't have an interesting event to report. */
2740 if (stopping_threads
== NOT_STOPPING_THREADS
)
2741 for_each_thread (resume_stopped_resumed_lwps
);
2743 /* ... and find an LWP with a status to report to the core, if
2745 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2747 return status_pending_p_callback (thread
, filter_ptid
);
2750 if (event_thread
!= NULL
)
2752 event_child
= get_thread_lwp (event_thread
);
2753 *wstatp
= event_child
->status_pending
;
2754 event_child
->status_pending_p
= 0;
2755 event_child
->status_pending
= 0;
2759 /* Check for zombie thread group leaders. Those can't be reaped
2760 until all other threads in the thread group are. */
2761 check_zombie_leaders ();
2763 auto not_stopped
= [&] (thread_info
*thread
)
2765 return not_stopped_callback (thread
, wait_ptid
);
2768 /* If there are no resumed children left in the set of LWPs we
2769 want to wait for, bail. We can't just block in
2770 waitpid/sigsuspend, because lwps might have been left stopped
2771 in trace-stop state, and we'd be stuck forever waiting for
2772 their status to change (which would only happen if we resumed
2773 them). Even if WNOHANG is set, this return code is preferred
2774 over 0 (below), as it is more detailed. */
2775 if (find_thread (not_stopped
) == NULL
)
2778 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2779 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2783 /* No interesting event to report to the caller. */
2784 if ((options
& WNOHANG
))
2787 debug_printf ("WNOHANG set, no event found\n");
2789 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2793 /* Block until we get an event reported with SIGCHLD. */
2795 debug_printf ("sigsuspend'ing\n");
2797 sigsuspend (&prev_mask
);
2798 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2802 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2804 current_thread
= event_thread
;
2806 return lwpid_of (event_thread
);
2809 /* Wait for an event from child(ren) PTID. PTIDs can be:
2810 minus_one_ptid, to specify any child; a pid PTID, specifying all
2811 lwps of a thread group; or a PTID representing a single lwp. Store
2812 the stop status through the status pointer WSTAT. OPTIONS is
2813 passed to the waitpid call. Return 0 if no event was found and
2814 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2815 was found. Return the PID of the stopped child otherwise. */
2818 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2820 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2823 /* Select one LWP out of those that have events pending. */
2826 select_event_lwp (struct lwp_info
**orig_lp
)
2828 int random_selector
;
2829 struct thread_info
*event_thread
= NULL
;
2831 /* In all-stop, give preference to the LWP that is being
2832 single-stepped. There will be at most one, and it's the LWP that
2833 the core is most interested in. If we didn't do this, then we'd
2834 have to handle pending step SIGTRAPs somehow in case the core
2835 later continues the previously-stepped thread, otherwise we'd
2836 report the pending SIGTRAP, and the core, not having stepped the
2837 thread, wouldn't understand what the trap was for, and therefore
2838 would report it to the user as a random signal. */
2841 event_thread
= find_thread ([] (thread_info
*thread
)
2843 lwp_info
*lp
= get_thread_lwp (thread
);
2845 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2846 && thread
->last_resume_kind
== resume_step
2847 && lp
->status_pending_p
);
2850 if (event_thread
!= NULL
)
2853 debug_printf ("SEL: Select single-step %s\n",
2854 target_pid_to_str (ptid_of (event_thread
)));
2857 if (event_thread
== NULL
)
2859 /* No single-stepping LWP. Select one at random, out of those
2860 which have had events. */
2862 /* First see how many events we have. */
2864 for_each_thread ([&] (thread_info
*thread
)
2866 lwp_info
*lp
= get_thread_lwp (thread
);
2868 /* Count only resumed LWPs that have an event pending. */
2869 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2870 && lp
->status_pending_p
)
2873 gdb_assert (num_events
> 0);
2875 /* Now randomly pick a LWP out of those that have had
2877 random_selector
= (int)
2878 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2880 if (debug_threads
&& num_events
> 1)
2881 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2882 num_events
, random_selector
);
2884 event_thread
= find_thread ([&] (thread_info
*thread
)
2886 lwp_info
*lp
= get_thread_lwp (thread
);
2888 /* Select only resumed LWPs that have an event pending. */
2889 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2890 && lp
->status_pending_p
)
2891 if (random_selector
-- == 0)
2898 if (event_thread
!= NULL
)
2900 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2902 /* Switch the event LWP. */
2903 *orig_lp
= event_lp
;
2907 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2911 unsuspend_all_lwps (struct lwp_info
*except
)
2913 for_each_thread ([&] (thread_info
*thread
)
2915 lwp_info
*lwp
= get_thread_lwp (thread
);
2918 lwp_suspended_decr (lwp
);
2922 static void move_out_of_jump_pad_callback (thread_info
*thread
);
2923 static bool stuck_in_jump_pad_callback (thread_info
*thread
);
2924 static bool lwp_running (thread_info
*thread
);
2925 static ptid_t
linux_wait_1 (ptid_t ptid
,
2926 struct target_waitstatus
*ourstatus
,
2927 int target_options
);
2929 /* Stabilize threads (move out of jump pads).
2931 If a thread is midway collecting a fast tracepoint, we need to
2932 finish the collection and move it out of the jump pad before
2933 reporting the signal.
2935 This avoids recursion while collecting (when a signal arrives
2936 midway, and the signal handler itself collects), which would trash
2937 the trace buffer. In case the user set a breakpoint in a signal
2938 handler, this avoids the backtrace showing the jump pad, etc..
2939 Most importantly, there are certain things we can't do safely if
2940 threads are stopped in a jump pad (or in its callee's). For
2943 - starting a new trace run. A thread still collecting the
2944 previous run, could trash the trace buffer when resumed. The trace
2945 buffer control structures would have been reset but the thread had
2946 no way to tell. The thread could even midway memcpy'ing to the
2947 buffer, which would mean that when resumed, it would clobber the
2948 trace buffer that had been set for a new run.
2950 - we can't rewrite/reuse the jump pads for new tracepoints
2951 safely. Say you do tstart while a thread is stopped midway while
2952 collecting. When the thread is later resumed, it finishes the
2953 collection, and returns to the jump pad, to execute the original
2954 instruction that was under the tracepoint jump at the time the
2955 older run had been started. If the jump pad had been rewritten
2956 since for something else in the new run, the thread would now
2957 execute the wrong / random instructions. */
2960 linux_stabilize_threads (void)
2962 thread_info
*thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
2964 if (thread_stuck
!= NULL
)
2967 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2968 lwpid_of (thread_stuck
));
2972 thread_info
*saved_thread
= current_thread
;
2974 stabilizing_threads
= 1;
2977 for_each_thread (move_out_of_jump_pad_callback
);
2979 /* Loop until all are stopped out of the jump pads. */
2980 while (find_thread (lwp_running
) != NULL
)
2982 struct target_waitstatus ourstatus
;
2983 struct lwp_info
*lwp
;
2986 /* Note that we go through the full wait even loop. While
2987 moving threads out of jump pad, we need to be able to step
2988 over internal breakpoints and such. */
2989 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2991 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2993 lwp
= get_thread_lwp (current_thread
);
2996 lwp_suspended_inc (lwp
);
2998 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2999 || current_thread
->last_resume_kind
== resume_stop
)
3001 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
3002 enqueue_one_deferred_signal (lwp
, &wstat
);
3007 unsuspend_all_lwps (NULL
);
3009 stabilizing_threads
= 0;
3011 current_thread
= saved_thread
;
3015 thread_stuck
= find_thread (stuck_in_jump_pad_callback
);
3017 if (thread_stuck
!= NULL
)
3018 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3019 lwpid_of (thread_stuck
));
3023 /* Convenience function that is called when the kernel reports an
3024 event that is not passed out to GDB. */
3027 ignore_event (struct target_waitstatus
*ourstatus
)
3029 /* If we got an event, there may still be others, as a single
3030 SIGCHLD can indicate more than one child stopped. This forces
3031 another target_wait call. */
3034 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3038 /* Convenience function that is called when the kernel reports an exit
3039 event. This decides whether to report the event to GDB as a
3040 process exit event, a thread exit event, or to suppress the
3044 filter_exit_event (struct lwp_info
*event_child
,
3045 struct target_waitstatus
*ourstatus
)
3047 client_state
&cs
= get_client_state ();
3048 struct thread_info
*thread
= get_lwp_thread (event_child
);
3049 ptid_t ptid
= ptid_of (thread
);
3051 if (!last_thread_of_process_p (pid_of (thread
)))
3053 if (cs
.report_thread_events
)
3054 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
3056 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3058 delete_lwp (event_child
);
3063 /* Returns 1 if GDB is interested in any event_child syscalls. */
3066 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
3068 struct thread_info
*thread
= get_lwp_thread (event_child
);
3069 struct process_info
*proc
= get_thread_process (thread
);
3071 return !proc
->syscalls_to_catch
.empty ();
3074 /* Returns 1 if GDB is interested in the event_child syscall.
3075 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3078 gdb_catch_this_syscall_p (struct lwp_info
*event_child
)
3081 struct thread_info
*thread
= get_lwp_thread (event_child
);
3082 struct process_info
*proc
= get_thread_process (thread
);
3084 if (proc
->syscalls_to_catch
.empty ())
3087 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
3090 get_syscall_trapinfo (event_child
, &sysno
);
3092 for (int iter
: proc
->syscalls_to_catch
)
3099 /* Wait for process, returns status. */
3102 linux_wait_1 (ptid_t ptid
,
3103 struct target_waitstatus
*ourstatus
, int target_options
)
3105 client_state
&cs
= get_client_state ();
3107 struct lwp_info
*event_child
;
3110 int step_over_finished
;
3111 int bp_explains_trap
;
3112 int maybe_internal_trap
;
3121 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3124 /* Translate generic target options into linux options. */
3126 if (target_options
& TARGET_WNOHANG
)
3129 bp_explains_trap
= 0;
3132 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3134 auto status_pending_p_any
= [&] (thread_info
*thread
)
3136 return status_pending_p_callback (thread
, minus_one_ptid
);
3139 auto not_stopped
= [&] (thread_info
*thread
)
3141 return not_stopped_callback (thread
, minus_one_ptid
);
3144 /* Find a resumed LWP, if any. */
3145 if (find_thread (status_pending_p_any
) != NULL
)
3147 else if (find_thread (not_stopped
) != NULL
)
3152 if (step_over_bkpt
== null_ptid
)
3153 pid
= linux_wait_for_event (ptid
, &w
, options
);
3157 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3158 target_pid_to_str (step_over_bkpt
));
3159 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3162 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3164 gdb_assert (target_options
& TARGET_WNOHANG
);
3168 debug_printf ("linux_wait_1 ret = null_ptid, "
3169 "TARGET_WAITKIND_IGNORE\n");
3173 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3180 debug_printf ("linux_wait_1 ret = null_ptid, "
3181 "TARGET_WAITKIND_NO_RESUMED\n");
3185 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3189 event_child
= get_thread_lwp (current_thread
);
3191 /* linux_wait_for_event only returns an exit status for the last
3192 child of a process. Report it. */
3193 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3197 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3198 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3202 debug_printf ("linux_wait_1 ret = %s, exited with "
3204 target_pid_to_str (ptid_of (current_thread
)),
3211 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3212 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3216 debug_printf ("linux_wait_1 ret = %s, terminated with "
3218 target_pid_to_str (ptid_of (current_thread
)),
3224 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3225 return filter_exit_event (event_child
, ourstatus
);
3227 return ptid_of (current_thread
);
3230 /* If step-over executes a breakpoint instruction, in the case of a
3231 hardware single step it means a gdb/gdbserver breakpoint had been
3232 planted on top of a permanent breakpoint, in the case of a software
3233 single step it may just mean that gdbserver hit the reinsert breakpoint.
3234 The PC has been adjusted by save_stop_reason to point at
3235 the breakpoint address.
3236 So in the case of the hardware single step advance the PC manually
3237 past the breakpoint and in the case of software single step advance only
3238 if it's not the single_step_breakpoint we are hitting.
3239 This avoids that a program would keep trapping a permanent breakpoint
3241 if (step_over_bkpt
!= null_ptid
3242 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3243 && (event_child
->stepping
3244 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3246 int increment_pc
= 0;
3247 int breakpoint_kind
= 0;
3248 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3251 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3252 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3256 debug_printf ("step-over for %s executed software breakpoint\n",
3257 target_pid_to_str (ptid_of (current_thread
)));
3260 if (increment_pc
!= 0)
3262 struct regcache
*regcache
3263 = get_thread_regcache (current_thread
, 1);
3265 event_child
->stop_pc
+= increment_pc
;
3266 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3268 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3269 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3273 /* If this event was not handled before, and is not a SIGTRAP, we
3274 report it. SIGILL and SIGSEGV are also treated as traps in case
3275 a breakpoint is inserted at the current PC. If this target does
3276 not support internal breakpoints at all, we also report the
3277 SIGTRAP without further processing; it's of no concern to us. */
3279 = (supports_breakpoints ()
3280 && (WSTOPSIG (w
) == SIGTRAP
3281 || ((WSTOPSIG (w
) == SIGILL
3282 || WSTOPSIG (w
) == SIGSEGV
)
3283 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3285 if (maybe_internal_trap
)
3287 /* Handle anything that requires bookkeeping before deciding to
3288 report the event or continue waiting. */
3290 /* First check if we can explain the SIGTRAP with an internal
3291 breakpoint, or if we should possibly report the event to GDB.
3292 Do this before anything that may remove or insert a
3294 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3296 /* We have a SIGTRAP, possibly a step-over dance has just
3297 finished. If so, tweak the state machine accordingly,
3298 reinsert breakpoints and delete any single-step
3300 step_over_finished
= finish_step_over (event_child
);
3302 /* Now invoke the callbacks of any internal breakpoints there. */
3303 check_breakpoints (event_child
->stop_pc
);
3305 /* Handle tracepoint data collecting. This may overflow the
3306 trace buffer, and cause a tracing stop, removing
3308 trace_event
= handle_tracepoints (event_child
);
3310 if (bp_explains_trap
)
3313 debug_printf ("Hit a gdbserver breakpoint.\n");
3318 /* We have some other signal, possibly a step-over dance was in
3319 progress, and it should be cancelled too. */
3320 step_over_finished
= finish_step_over (event_child
);
3323 /* We have all the data we need. Either report the event to GDB, or
3324 resume threads and keep waiting for more. */
3326 /* If we're collecting a fast tracepoint, finish the collection and
3327 move out of the jump pad before delivering a signal. See
3328 linux_stabilize_threads. */
3331 && WSTOPSIG (w
) != SIGTRAP
3332 && supports_fast_tracepoints ()
3333 && agent_loaded_p ())
3336 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3337 "to defer or adjust it.\n",
3338 WSTOPSIG (w
), lwpid_of (current_thread
));
3340 /* Allow debugging the jump pad itself. */
3341 if (current_thread
->last_resume_kind
!= resume_step
3342 && maybe_move_out_of_jump_pad (event_child
, &w
))
3344 enqueue_one_deferred_signal (event_child
, &w
);
3347 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3348 WSTOPSIG (w
), lwpid_of (current_thread
));
3350 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3354 return ignore_event (ourstatus
);
3358 if (event_child
->collecting_fast_tracepoint
3359 != fast_tpoint_collect_result::not_collecting
)
3362 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3363 "Check if we're already there.\n",
3364 lwpid_of (current_thread
),
3365 (int) event_child
->collecting_fast_tracepoint
);
3369 event_child
->collecting_fast_tracepoint
3370 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3372 if (event_child
->collecting_fast_tracepoint
3373 != fast_tpoint_collect_result::before_insn
)
3375 /* No longer need this breakpoint. */
3376 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3379 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3380 "stopping all threads momentarily.\n");
3382 /* Other running threads could hit this breakpoint.
3383 We don't handle moribund locations like GDB does,
3384 instead we always pause all threads when removing
3385 breakpoints, so that any step-over or
3386 decr_pc_after_break adjustment is always taken
3387 care of while the breakpoint is still
3389 stop_all_lwps (1, event_child
);
3391 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3392 event_child
->exit_jump_pad_bkpt
= NULL
;
3394 unstop_all_lwps (1, event_child
);
3396 gdb_assert (event_child
->suspended
>= 0);
3400 if (event_child
->collecting_fast_tracepoint
3401 == fast_tpoint_collect_result::not_collecting
)
3404 debug_printf ("fast tracepoint finished "
3405 "collecting successfully.\n");
3407 /* We may have a deferred signal to report. */
3408 if (dequeue_one_deferred_signal (event_child
, &w
))
3411 debug_printf ("dequeued one signal.\n");
3416 debug_printf ("no deferred signals.\n");
3418 if (stabilizing_threads
)
3420 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3421 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3425 debug_printf ("linux_wait_1 ret = %s, stopped "
3426 "while stabilizing threads\n",
3427 target_pid_to_str (ptid_of (current_thread
)));
3431 return ptid_of (current_thread
);
3437 /* Check whether GDB would be interested in this event. */
3439 /* Check if GDB is interested in this syscall. */
3441 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3442 && !gdb_catch_this_syscall_p (event_child
))
3446 debug_printf ("Ignored syscall for LWP %ld.\n",
3447 lwpid_of (current_thread
));
3450 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3455 return ignore_event (ourstatus
);
3458 /* If GDB is not interested in this signal, don't stop other
3459 threads, and don't report it to GDB. Just resume the inferior
3460 right away. We do this for threading-related signals as well as
3461 any that GDB specifically requested we ignore. But never ignore
3462 SIGSTOP if we sent it ourselves, and do not ignore signals when
3463 stepping - they may require special handling to skip the signal
3464 handler. Also never ignore signals that could be caused by a
3467 && current_thread
->last_resume_kind
!= resume_step
3469 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3470 (current_process ()->priv
->thread_db
!= NULL
3471 && (WSTOPSIG (w
) == __SIGRTMIN
3472 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3475 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3476 && !(WSTOPSIG (w
) == SIGSTOP
3477 && current_thread
->last_resume_kind
== resume_stop
)
3478 && !linux_wstatus_maybe_breakpoint (w
))))
3480 siginfo_t info
, *info_p
;
3483 debug_printf ("Ignored signal %d for LWP %ld.\n",
3484 WSTOPSIG (w
), lwpid_of (current_thread
));
3486 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3487 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3492 if (step_over_finished
)
3494 /* We cancelled this thread's step-over above. We still
3495 need to unsuspend all other LWPs, and set them back
3496 running again while the signal handler runs. */
3497 unsuspend_all_lwps (event_child
);
3499 /* Enqueue the pending signal info so that proceed_all_lwps
3501 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3503 proceed_all_lwps ();
3507 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3508 WSTOPSIG (w
), info_p
);
3514 return ignore_event (ourstatus
);
3517 /* Note that all addresses are always "out of the step range" when
3518 there's no range to begin with. */
3519 in_step_range
= lwp_in_step_range (event_child
);
3521 /* If GDB wanted this thread to single step, and the thread is out
3522 of the step range, we always want to report the SIGTRAP, and let
3523 GDB handle it. Watchpoints should always be reported. So should
3524 signals we can't explain. A SIGTRAP we can't explain could be a
3525 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3526 do, we're be able to handle GDB breakpoints on top of internal
3527 breakpoints, by handling the internal breakpoint and still
3528 reporting the event to GDB. If we don't, we're out of luck, GDB
3529 won't see the breakpoint hit. If we see a single-step event but
3530 the thread should be continuing, don't pass the trap to gdb.
3531 That indicates that we had previously finished a single-step but
3532 left the single-step pending -- see
3533 complete_ongoing_step_over. */
3534 report_to_gdb
= (!maybe_internal_trap
3535 || (current_thread
->last_resume_kind
== resume_step
3537 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3539 && !bp_explains_trap
3541 && !step_over_finished
3542 && !(current_thread
->last_resume_kind
== resume_continue
3543 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3544 || (gdb_breakpoint_here (event_child
->stop_pc
)
3545 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3546 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3547 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3549 run_breakpoint_commands (event_child
->stop_pc
);
3551 /* We found no reason GDB would want us to stop. We either hit one
3552 of our own breakpoints, or finished an internal step GDB
3553 shouldn't know about. */
3558 if (bp_explains_trap
)
3559 debug_printf ("Hit a gdbserver breakpoint.\n");
3560 if (step_over_finished
)
3561 debug_printf ("Step-over finished.\n");
3563 debug_printf ("Tracepoint event.\n");
3564 if (lwp_in_step_range (event_child
))
3565 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3566 paddress (event_child
->stop_pc
),
3567 paddress (event_child
->step_range_start
),
3568 paddress (event_child
->step_range_end
));
3571 /* We're not reporting this breakpoint to GDB, so apply the
3572 decr_pc_after_break adjustment to the inferior's regcache
3575 if (the_low_target
.set_pc
!= NULL
)
3577 struct regcache
*regcache
3578 = get_thread_regcache (current_thread
, 1);
3579 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3582 if (step_over_finished
)
3584 /* If we have finished stepping over a breakpoint, we've
3585 stopped and suspended all LWPs momentarily except the
3586 stepping one. This is where we resume them all again.
3587 We're going to keep waiting, so use proceed, which
3588 handles stepping over the next breakpoint. */
3589 unsuspend_all_lwps (event_child
);
3593 /* Remove the single-step breakpoints if any. Note that
3594 there isn't single-step breakpoint if we finished stepping
3596 if (can_software_single_step ()
3597 && has_single_step_breakpoints (current_thread
))
3599 stop_all_lwps (0, event_child
);
3600 delete_single_step_breakpoints (current_thread
);
3601 unstop_all_lwps (0, event_child
);
3606 debug_printf ("proceeding all threads.\n");
3607 proceed_all_lwps ();
3612 return ignore_event (ourstatus
);
3617 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3620 = target_waitstatus_to_string (&event_child
->waitstatus
);
3622 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3623 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3625 if (current_thread
->last_resume_kind
== resume_step
)
3627 if (event_child
->step_range_start
== event_child
->step_range_end
)
3628 debug_printf ("GDB wanted to single-step, reporting event.\n");
3629 else if (!lwp_in_step_range (event_child
))
3630 debug_printf ("Out of step range, reporting event.\n");
3632 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3633 debug_printf ("Stopped by watchpoint.\n");
3634 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3635 debug_printf ("Stopped by GDB breakpoint.\n");
3637 debug_printf ("Hit a non-gdbserver trap event.\n");
3640 /* Alright, we're going to report a stop. */
3642 /* Remove single-step breakpoints. */
3643 if (can_software_single_step ())
3645 /* Remove single-step breakpoints or not. It it is true, stop all
3646 lwps, so that other threads won't hit the breakpoint in the
3648 int remove_single_step_breakpoints_p
= 0;
3652 remove_single_step_breakpoints_p
3653 = has_single_step_breakpoints (current_thread
);
3657 /* In all-stop, a stop reply cancels all previous resume
3658 requests. Delete all single-step breakpoints. */
3660 find_thread ([&] (thread_info
*thread
) {
3661 if (has_single_step_breakpoints (thread
))
3663 remove_single_step_breakpoints_p
= 1;
3671 if (remove_single_step_breakpoints_p
)
3673 /* If we remove single-step breakpoints from memory, stop all lwps,
3674 so that other threads won't hit the breakpoint in the staled
3676 stop_all_lwps (0, event_child
);
3680 gdb_assert (has_single_step_breakpoints (current_thread
));
3681 delete_single_step_breakpoints (current_thread
);
3685 for_each_thread ([] (thread_info
*thread
){
3686 if (has_single_step_breakpoints (thread
))
3687 delete_single_step_breakpoints (thread
);
3691 unstop_all_lwps (0, event_child
);
3695 if (!stabilizing_threads
)
3697 /* In all-stop, stop all threads. */
3699 stop_all_lwps (0, NULL
);
3701 if (step_over_finished
)
3705 /* If we were doing a step-over, all other threads but
3706 the stepping one had been paused in start_step_over,
3707 with their suspend counts incremented. We don't want
3708 to do a full unstop/unpause, because we're in
3709 all-stop mode (so we want threads stopped), but we
3710 still need to unsuspend the other threads, to
3711 decrement their `suspended' count back. */
3712 unsuspend_all_lwps (event_child
);
3716 /* If we just finished a step-over, then all threads had
3717 been momentarily paused. In all-stop, that's fine,
3718 we want threads stopped by now anyway. In non-stop,
3719 we need to re-resume threads that GDB wanted to be
3721 unstop_all_lwps (1, event_child
);
3725 /* If we're not waiting for a specific LWP, choose an event LWP
3726 from among those that have had events. Giving equal priority
3727 to all LWPs that have had events helps prevent
3729 if (ptid
== minus_one_ptid
)
3731 event_child
->status_pending_p
= 1;
3732 event_child
->status_pending
= w
;
3734 select_event_lwp (&event_child
);
3736 /* current_thread and event_child must stay in sync. */
3737 current_thread
= get_lwp_thread (event_child
);
3739 event_child
->status_pending_p
= 0;
3740 w
= event_child
->status_pending
;
3744 /* Stabilize threads (move out of jump pads). */
3746 stabilize_threads ();
3750 /* If we just finished a step-over, then all threads had been
3751 momentarily paused. In all-stop, that's fine, we want
3752 threads stopped by now anyway. In non-stop, we need to
3753 re-resume threads that GDB wanted to be running. */
3754 if (step_over_finished
)
3755 unstop_all_lwps (1, event_child
);
3758 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3760 /* If the reported event is an exit, fork, vfork or exec, let
3763 /* Break the unreported fork relationship chain. */
3764 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3765 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3767 event_child
->fork_relative
->fork_relative
= NULL
;
3768 event_child
->fork_relative
= NULL
;
3771 *ourstatus
= event_child
->waitstatus
;
3772 /* Clear the event lwp's waitstatus since we handled it already. */
3773 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3776 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3778 /* Now that we've selected our final event LWP, un-adjust its PC if
3779 it was a software breakpoint, and the client doesn't know we can
3780 adjust the breakpoint ourselves. */
3781 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3782 && !cs
.swbreak_feature
)
3784 int decr_pc
= the_low_target
.decr_pc_after_break
;
3788 struct regcache
*regcache
3789 = get_thread_regcache (current_thread
, 1);
3790 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3794 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3796 get_syscall_trapinfo (event_child
,
3797 &ourstatus
->value
.syscall_number
);
3798 ourstatus
->kind
= event_child
->syscall_state
;
3800 else if (current_thread
->last_resume_kind
== resume_stop
3801 && WSTOPSIG (w
) == SIGSTOP
)
3803 /* A thread that has been requested to stop by GDB with vCont;t,
3804 and it stopped cleanly, so report as SIG0. The use of
3805 SIGSTOP is an implementation detail. */
3806 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3808 else if (current_thread
->last_resume_kind
== resume_stop
3809 && WSTOPSIG (w
) != SIGSTOP
)
3811 /* A thread that has been requested to stop by GDB with vCont;t,
3812 but, it stopped for other reasons. */
3813 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3815 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3817 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3820 gdb_assert (step_over_bkpt
== null_ptid
);
3824 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3825 target_pid_to_str (ptid_of (current_thread
)),
3826 ourstatus
->kind
, ourstatus
->value
.sig
);
3830 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3831 return filter_exit_event (event_child
, ourstatus
);
3833 return ptid_of (current_thread
);
3836 /* Get rid of any pending event in the pipe. */
3838 async_file_flush (void)
3844 ret
= read (linux_event_pipe
[0], &buf
, 1);
3845 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3848 /* Put something in the pipe, so the event loop wakes up. */
3850 async_file_mark (void)
3854 async_file_flush ();
3857 ret
= write (linux_event_pipe
[1], "+", 1);
3858 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3860 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3861 be awakened anyway. */
3865 linux_wait (ptid_t ptid
,
3866 struct target_waitstatus
*ourstatus
, int target_options
)
3870 /* Flush the async file first. */
3871 if (target_is_async_p ())
3872 async_file_flush ();
3876 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3878 while ((target_options
& TARGET_WNOHANG
) == 0
3879 && event_ptid
== null_ptid
3880 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3882 /* If at least one stop was reported, there may be more. A single
3883 SIGCHLD can signal more than one child stop. */
3884 if (target_is_async_p ()
3885 && (target_options
& TARGET_WNOHANG
) != 0
3886 && event_ptid
!= null_ptid
)
3892 /* Send a signal to an LWP. */
3895 kill_lwp (unsigned long lwpid
, int signo
)
3900 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3901 if (errno
== ENOSYS
)
3903 /* If tkill fails, then we are not using nptl threads, a
3904 configuration we no longer support. */
3905 perror_with_name (("tkill"));
3911 linux_stop_lwp (struct lwp_info
*lwp
)
3917 send_sigstop (struct lwp_info
*lwp
)
3921 pid
= lwpid_of (get_lwp_thread (lwp
));
3923 /* If we already have a pending stop signal for this process, don't
3925 if (lwp
->stop_expected
)
3928 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3934 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3936 lwp
->stop_expected
= 1;
3937 kill_lwp (pid
, SIGSTOP
);
3941 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3943 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3945 /* Ignore EXCEPT. */
3955 /* Increment the suspend count of an LWP, and stop it, if not stopped
3958 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3960 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3962 /* Ignore EXCEPT. */
3966 lwp_suspended_inc (lwp
);
3968 send_sigstop (thread
, except
);
3972 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3974 /* Store the exit status for later. */
3975 lwp
->status_pending_p
= 1;
3976 lwp
->status_pending
= wstat
;
3978 /* Store in waitstatus as well, as there's nothing else to process
3980 if (WIFEXITED (wstat
))
3982 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3983 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3985 else if (WIFSIGNALED (wstat
))
3987 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3988 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3991 /* Prevent trying to stop it. */
3994 /* No further stops are expected from a dead lwp. */
3995 lwp
->stop_expected
= 0;
3998 /* Return true if LWP has exited already, and has a pending exit event
3999 to report to GDB. */
4002 lwp_is_marked_dead (struct lwp_info
*lwp
)
4004 return (lwp
->status_pending_p
4005 && (WIFEXITED (lwp
->status_pending
)
4006 || WIFSIGNALED (lwp
->status_pending
)));
4009 /* Wait for all children to stop for the SIGSTOPs we just queued. */
4012 wait_for_sigstop (void)
4014 struct thread_info
*saved_thread
;
4019 saved_thread
= current_thread
;
4020 if (saved_thread
!= NULL
)
4021 saved_tid
= saved_thread
->id
;
4023 saved_tid
= null_ptid
; /* avoid bogus unused warning */
4026 debug_printf ("wait_for_sigstop: pulling events\n");
4028 /* Passing NULL_PTID as filter indicates we want all events to be
4029 left pending. Eventually this returns when there are no
4030 unwaited-for children left. */
4031 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4033 gdb_assert (ret
== -1);
4035 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
4036 current_thread
= saved_thread
;
4040 debug_printf ("Previously current thread died.\n");
4042 /* We can't change the current inferior behind GDB's back,
4043 otherwise, a subsequent command may apply to the wrong
4045 current_thread
= NULL
;
4049 /* Returns true if THREAD is stopped in a jump pad, and we can't
4050 move it out, because we need to report the stop event to GDB. For
4051 example, if the user puts a breakpoint in the jump pad, it's
4052 because she wants to debug it. */
4055 stuck_in_jump_pad_callback (thread_info
*thread
)
4057 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4059 if (lwp
->suspended
!= 0)
4061 internal_error (__FILE__
, __LINE__
,
4062 "LWP %ld is suspended, suspended=%d\n",
4063 lwpid_of (thread
), lwp
->suspended
);
4065 gdb_assert (lwp
->stopped
);
4067 /* Allow debugging the jump pad, gdb_collect, etc.. */
4068 return (supports_fast_tracepoints ()
4069 && agent_loaded_p ()
4070 && (gdb_breakpoint_here (lwp
->stop_pc
)
4071 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
4072 || thread
->last_resume_kind
== resume_step
)
4073 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
4074 != fast_tpoint_collect_result::not_collecting
));
4078 move_out_of_jump_pad_callback (thread_info
*thread
)
4080 struct thread_info
*saved_thread
;
4081 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4084 if (lwp
->suspended
!= 0)
4086 internal_error (__FILE__
, __LINE__
,
4087 "LWP %ld is suspended, suspended=%d\n",
4088 lwpid_of (thread
), lwp
->suspended
);
4090 gdb_assert (lwp
->stopped
);
4092 /* For gdb_breakpoint_here. */
4093 saved_thread
= current_thread
;
4094 current_thread
= thread
;
4096 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
4098 /* Allow debugging the jump pad, gdb_collect, etc. */
4099 if (!gdb_breakpoint_here (lwp
->stop_pc
)
4100 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
4101 && thread
->last_resume_kind
!= resume_step
4102 && maybe_move_out_of_jump_pad (lwp
, wstat
))
4105 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4110 lwp
->status_pending_p
= 0;
4111 enqueue_one_deferred_signal (lwp
, wstat
);
4114 debug_printf ("Signal %d for LWP %ld deferred "
4116 WSTOPSIG (*wstat
), lwpid_of (thread
));
4119 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
4122 lwp_suspended_inc (lwp
);
4124 current_thread
= saved_thread
;
4128 lwp_running (thread_info
*thread
)
4130 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4132 if (lwp_is_marked_dead (lwp
))
4135 return !lwp
->stopped
;
4138 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4139 If SUSPEND, then also increase the suspend count of every LWP,
4143 stop_all_lwps (int suspend
, struct lwp_info
*except
)
4145 /* Should not be called recursively. */
4146 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
4151 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4152 suspend
? "stop-and-suspend" : "stop",
4154 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
4158 stopping_threads
= (suspend
4159 ? STOPPING_AND_SUSPENDING_THREADS
4160 : STOPPING_THREADS
);
4163 for_each_thread ([&] (thread_info
*thread
)
4165 suspend_and_send_sigstop (thread
, except
);
4168 for_each_thread ([&] (thread_info
*thread
)
4170 send_sigstop (thread
, except
);
4173 wait_for_sigstop ();
4174 stopping_threads
= NOT_STOPPING_THREADS
;
4178 debug_printf ("stop_all_lwps done, setting stopping_threads "
4179 "back to !stopping\n");
4184 /* Enqueue one signal in the chain of signals which need to be
4185 delivered to this process on next resume. */
4188 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4190 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4192 p_sig
->prev
= lwp
->pending_signals
;
4193 p_sig
->signal
= signal
;
4195 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4197 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4198 lwp
->pending_signals
= p_sig
;
4201 /* Install breakpoints for software single stepping. */
4204 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
4206 struct thread_info
*thread
= get_lwp_thread (lwp
);
4207 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4209 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4211 current_thread
= thread
;
4212 std::vector
<CORE_ADDR
> next_pcs
= the_low_target
.get_next_pcs (regcache
);
4214 for (CORE_ADDR pc
: next_pcs
)
4215 set_single_step_breakpoint (pc
, current_ptid
);
4218 /* Single step via hardware or software single step.
4219 Return 1 if hardware single stepping, 0 if software single stepping
4220 or can't single step. */
4223 single_step (struct lwp_info
* lwp
)
4227 if (can_hardware_single_step ())
4231 else if (can_software_single_step ())
4233 install_software_single_step_breakpoints (lwp
);
4239 debug_printf ("stepping is not implemented on this target");
4245 /* The signal can be delivered to the inferior if we are not trying to
4246 finish a fast tracepoint collect. Since signal can be delivered in
4247 the step-over, the program may go to signal handler and trap again
4248 after return from the signal handler. We can live with the spurious
4252 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4254 return (lwp
->collecting_fast_tracepoint
4255 == fast_tpoint_collect_result::not_collecting
);
4258 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4259 SIGNAL is nonzero, give it that signal. */
4262 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4263 int step
, int signal
, siginfo_t
*info
)
4265 struct thread_info
*thread
= get_lwp_thread (lwp
);
4266 struct thread_info
*saved_thread
;
4268 struct process_info
*proc
= get_thread_process (thread
);
4270 /* Note that target description may not be initialised
4271 (proc->tdesc == NULL) at this point because the program hasn't
4272 stopped at the first instruction yet. It means GDBserver skips
4273 the extra traps from the wrapper program (see option --wrapper).
4274 Code in this function that requires register access should be
4275 guarded by proc->tdesc == NULL or something else. */
4277 if (lwp
->stopped
== 0)
4280 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4282 fast_tpoint_collect_result fast_tp_collecting
4283 = lwp
->collecting_fast_tracepoint
;
4285 gdb_assert (!stabilizing_threads
4286 || (fast_tp_collecting
4287 != fast_tpoint_collect_result::not_collecting
));
4289 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4290 user used the "jump" command, or "set $pc = foo"). */
4291 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4293 /* Collecting 'while-stepping' actions doesn't make sense
4295 release_while_stepping_state_list (thread
);
4298 /* If we have pending signals or status, and a new signal, enqueue the
4299 signal. Also enqueue the signal if it can't be delivered to the
4300 inferior right now. */
4302 && (lwp
->status_pending_p
4303 || lwp
->pending_signals
!= NULL
4304 || !lwp_signal_can_be_delivered (lwp
)))
4306 enqueue_pending_signal (lwp
, signal
, info
);
4308 /* Postpone any pending signal. It was enqueued above. */
4312 if (lwp
->status_pending_p
)
4315 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4316 " has pending status\n",
4317 lwpid_of (thread
), step
? "step" : "continue",
4318 lwp
->stop_expected
? "expected" : "not expected");
4322 saved_thread
= current_thread
;
4323 current_thread
= thread
;
4325 /* This bit needs some thinking about. If we get a signal that
4326 we must report while a single-step reinsert is still pending,
4327 we often end up resuming the thread. It might be better to
4328 (ew) allow a stack of pending events; then we could be sure that
4329 the reinsert happened right away and not lose any signals.
4331 Making this stack would also shrink the window in which breakpoints are
4332 uninserted (see comment in linux_wait_for_lwp) but not enough for
4333 complete correctness, so it won't solve that problem. It may be
4334 worthwhile just to solve this one, however. */
4335 if (lwp
->bp_reinsert
!= 0)
4338 debug_printf (" pending reinsert at 0x%s\n",
4339 paddress (lwp
->bp_reinsert
));
4341 if (can_hardware_single_step ())
4343 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4346 warning ("BAD - reinserting but not stepping.");
4348 warning ("BAD - reinserting and suspended(%d).",
4353 step
= maybe_hw_step (thread
);
4356 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4359 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4360 " (exit-jump-pad-bkpt)\n",
4363 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4366 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4367 " single-stepping\n",
4370 if (can_hardware_single_step ())
4374 internal_error (__FILE__
, __LINE__
,
4375 "moving out of jump pad single-stepping"
4376 " not implemented on this target");
4380 /* If we have while-stepping actions in this thread set it stepping.
4381 If we have a signal to deliver, it may or may not be set to
4382 SIG_IGN, we don't know. Assume so, and allow collecting
4383 while-stepping into a signal handler. A possible smart thing to
4384 do would be to set an internal breakpoint at the signal return
4385 address, continue, and carry on catching this while-stepping
4386 action only when that breakpoint is hit. A future
4388 if (thread
->while_stepping
!= NULL
)
4391 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4394 step
= single_step (lwp
);
4397 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4399 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4401 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4405 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4406 (long) lwp
->stop_pc
);
4410 /* If we have pending signals, consume one if it can be delivered to
4412 if (lwp
->pending_signals
!= NULL
&& lwp_signal_can_be_delivered (lwp
))
4414 struct pending_signals
**p_sig
;
4416 p_sig
= &lwp
->pending_signals
;
4417 while ((*p_sig
)->prev
!= NULL
)
4418 p_sig
= &(*p_sig
)->prev
;
4420 signal
= (*p_sig
)->signal
;
4421 if ((*p_sig
)->info
.si_signo
!= 0)
4422 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4430 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4431 lwpid_of (thread
), step
? "step" : "continue", signal
,
4432 lwp
->stop_expected
? "expected" : "not expected");
4434 if (the_low_target
.prepare_to_resume
!= NULL
)
4435 the_low_target
.prepare_to_resume (lwp
);
4437 regcache_invalidate_thread (thread
);
4439 lwp
->stepping
= step
;
4441 ptrace_request
= PTRACE_SINGLESTEP
;
4442 else if (gdb_catching_syscalls_p (lwp
))
4443 ptrace_request
= PTRACE_SYSCALL
;
4445 ptrace_request
= PTRACE_CONT
;
4446 ptrace (ptrace_request
,
4448 (PTRACE_TYPE_ARG3
) 0,
4449 /* Coerce to a uintptr_t first to avoid potential gcc warning
4450 of coercing an 8 byte integer to a 4 byte pointer. */
4451 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4453 current_thread
= saved_thread
;
4455 perror_with_name ("resuming thread");
4457 /* Successfully resumed. Clear state that no longer makes sense,
4458 and mark the LWP as running. Must not do this before resuming
4459 otherwise if that fails other code will be confused. E.g., we'd
4460 later try to stop the LWP and hang forever waiting for a stop
4461 status. Note that we must not throw after this is cleared,
4462 otherwise handle_zombie_lwp_error would get confused. */
4464 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4467 /* Called when we try to resume a stopped LWP and that errors out. If
4468 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4469 or about to become), discard the error, clear any pending status
4470 the LWP may have, and return true (we'll collect the exit status
4471 soon enough). Otherwise, return false. */
4474 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4476 struct thread_info
*thread
= get_lwp_thread (lp
);
4478 /* If we get an error after resuming the LWP successfully, we'd
4479 confuse !T state for the LWP being gone. */
4480 gdb_assert (lp
->stopped
);
4482 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4483 because even if ptrace failed with ESRCH, the tracee may be "not
4484 yet fully dead", but already refusing ptrace requests. In that
4485 case the tracee has 'R (Running)' state for a little bit
4486 (observed in Linux 3.18). See also the note on ESRCH in the
4487 ptrace(2) man page. Instead, check whether the LWP has any state
4488 other than ptrace-stopped. */
4490 /* Don't assume anything if /proc/PID/status can't be read. */
4491 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4493 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4494 lp
->status_pending_p
= 0;
4500 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4501 disappears while we try to resume it. */
4504 linux_resume_one_lwp (struct lwp_info
*lwp
,
4505 int step
, int signal
, siginfo_t
*info
)
4509 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4511 CATCH (ex
, RETURN_MASK_ERROR
)
4513 if (!check_ptrace_stopped_lwp_gone (lwp
))
4514 throw_exception (ex
);
4519 /* This function is called once per thread via for_each_thread.
4520 We look up which resume request applies to THREAD and mark it with a
4521 pointer to the appropriate resume request.
4523 This algorithm is O(threads * resume elements), but resume elements
4524 is small (and will remain small at least until GDB supports thread
4528 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4530 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4532 for (int ndx
= 0; ndx
< n
; ndx
++)
4534 ptid_t ptid
= resume
[ndx
].thread
;
4535 if (ptid
== minus_one_ptid
4536 || ptid
== thread
->id
4537 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4539 || (ptid
.pid () == pid_of (thread
)
4541 || ptid
.lwp () == -1)))
4543 if (resume
[ndx
].kind
== resume_stop
4544 && thread
->last_resume_kind
== resume_stop
)
4547 debug_printf ("already %s LWP %ld at GDB's request\n",
4548 (thread
->last_status
.kind
4549 == TARGET_WAITKIND_STOPPED
)
4557 /* Ignore (wildcard) resume requests for already-resumed
4559 if (resume
[ndx
].kind
!= resume_stop
4560 && thread
->last_resume_kind
!= resume_stop
)
4563 debug_printf ("already %s LWP %ld at GDB's request\n",
4564 (thread
->last_resume_kind
4572 /* Don't let wildcard resumes resume fork children that GDB
4573 does not yet know are new fork children. */
4574 if (lwp
->fork_relative
!= NULL
)
4576 struct lwp_info
*rel
= lwp
->fork_relative
;
4578 if (rel
->status_pending_p
4579 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4580 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4583 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4589 /* If the thread has a pending event that has already been
4590 reported to GDBserver core, but GDB has not pulled the
4591 event out of the vStopped queue yet, likewise, ignore the
4592 (wildcard) resume request. */
4593 if (in_queued_stop_replies (thread
->id
))
4596 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4601 lwp
->resume
= &resume
[ndx
];
4602 thread
->last_resume_kind
= lwp
->resume
->kind
;
4604 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4605 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4607 /* If we had a deferred signal to report, dequeue one now.
4608 This can happen if LWP gets more than one signal while
4609 trying to get out of a jump pad. */
4611 && !lwp
->status_pending_p
4612 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4614 lwp
->status_pending_p
= 1;
4617 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4618 "leaving status pending.\n",
4619 WSTOPSIG (lwp
->status_pending
),
4627 /* No resume action for this thread. */
4631 /* find_thread callback for linux_resume. Return true if this lwp has an
4632 interesting status pending. */
4635 resume_status_pending_p (thread_info
*thread
)
4637 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4639 /* LWPs which will not be resumed are not interesting, because
4640 we might not wait for them next time through linux_wait. */
4641 if (lwp
->resume
== NULL
)
4644 return thread_still_has_status_pending_p (thread
);
4647 /* Return 1 if this lwp that GDB wants running is stopped at an
4648 internal breakpoint that we need to step over. It assumes that any
4649 required STOP_PC adjustment has already been propagated to the
4650 inferior's regcache. */
4653 need_step_over_p (thread_info
*thread
)
4655 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4656 struct thread_info
*saved_thread
;
4658 struct process_info
*proc
= get_thread_process (thread
);
4660 /* GDBserver is skipping the extra traps from the wrapper program,
4661 don't have to do step over. */
4662 if (proc
->tdesc
== NULL
)
4665 /* LWPs which will not be resumed are not interesting, because we
4666 might not wait for them next time through linux_wait. */
4671 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4676 if (thread
->last_resume_kind
== resume_stop
)
4679 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4685 gdb_assert (lwp
->suspended
>= 0);
4690 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4695 if (lwp
->status_pending_p
)
4698 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4704 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4708 /* If the PC has changed since we stopped, then don't do anything,
4709 and let the breakpoint/tracepoint be hit. This happens if, for
4710 instance, GDB handled the decr_pc_after_break subtraction itself,
4711 GDB is OOL stepping this thread, or the user has issued a "jump"
4712 command, or poked thread's registers herself. */
4713 if (pc
!= lwp
->stop_pc
)
4716 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4717 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4719 paddress (lwp
->stop_pc
), paddress (pc
));
4723 /* On software single step target, resume the inferior with signal
4724 rather than stepping over. */
4725 if (can_software_single_step ()
4726 && lwp
->pending_signals
!= NULL
4727 && lwp_signal_can_be_delivered (lwp
))
4730 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4737 saved_thread
= current_thread
;
4738 current_thread
= thread
;
4740 /* We can only step over breakpoints we know about. */
4741 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4743 /* Don't step over a breakpoint that GDB expects to hit
4744 though. If the condition is being evaluated on the target's side
4745 and it evaluate to false, step over this breakpoint as well. */
4746 if (gdb_breakpoint_here (pc
)
4747 && gdb_condition_true_at_breakpoint (pc
)
4748 && gdb_no_commands_at_breakpoint (pc
))
4751 debug_printf ("Need step over [LWP %ld]? yes, but found"
4752 " GDB breakpoint at 0x%s; skipping step over\n",
4753 lwpid_of (thread
), paddress (pc
));
4755 current_thread
= saved_thread
;
4761 debug_printf ("Need step over [LWP %ld]? yes, "
4762 "found breakpoint at 0x%s\n",
4763 lwpid_of (thread
), paddress (pc
));
4765 /* We've found an lwp that needs stepping over --- return 1 so
4766 that find_thread stops looking. */
4767 current_thread
= saved_thread
;
4773 current_thread
= saved_thread
;
4776 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4778 lwpid_of (thread
), paddress (pc
));
4783 /* Start a step-over operation on LWP. When LWP stopped at a
4784 breakpoint, to make progress, we need to remove the breakpoint out
4785 of the way. If we let other threads run while we do that, they may
4786 pass by the breakpoint location and miss hitting it. To avoid
4787 that, a step-over momentarily stops all threads while LWP is
4788 single-stepped by either hardware or software while the breakpoint
4789 is temporarily uninserted from the inferior. When the single-step
4790 finishes, we reinsert the breakpoint, and let all threads that are
4791 supposed to be running, run again. */
4794 start_step_over (struct lwp_info
*lwp
)
4796 struct thread_info
*thread
= get_lwp_thread (lwp
);
4797 struct thread_info
*saved_thread
;
4802 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4805 stop_all_lwps (1, lwp
);
4807 if (lwp
->suspended
!= 0)
4809 internal_error (__FILE__
, __LINE__
,
4810 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4815 debug_printf ("Done stopping all threads for step-over.\n");
4817 /* Note, we should always reach here with an already adjusted PC,
4818 either by GDB (if we're resuming due to GDB's request), or by our
4819 caller, if we just finished handling an internal breakpoint GDB
4820 shouldn't care about. */
4823 saved_thread
= current_thread
;
4824 current_thread
= thread
;
4826 lwp
->bp_reinsert
= pc
;
4827 uninsert_breakpoints_at (pc
);
4828 uninsert_fast_tracepoint_jumps_at (pc
);
4830 step
= single_step (lwp
);
4832 current_thread
= saved_thread
;
4834 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4836 /* Require next event from this LWP. */
4837 step_over_bkpt
= thread
->id
;
4841 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4842 start_step_over, if still there, and delete any single-step
4843 breakpoints we've set, on non hardware single-step targets. */
4846 finish_step_over (struct lwp_info
*lwp
)
4848 if (lwp
->bp_reinsert
!= 0)
4850 struct thread_info
*saved_thread
= current_thread
;
4853 debug_printf ("Finished step over.\n");
4855 current_thread
= get_lwp_thread (lwp
);
4857 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4858 may be no breakpoint to reinsert there by now. */
4859 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4860 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4862 lwp
->bp_reinsert
= 0;
4864 /* Delete any single-step breakpoints. No longer needed. We
4865 don't have to worry about other threads hitting this trap,
4866 and later not being able to explain it, because we were
4867 stepping over a breakpoint, and we hold all threads but
4868 LWP stopped while doing that. */
4869 if (!can_hardware_single_step ())
4871 gdb_assert (has_single_step_breakpoints (current_thread
));
4872 delete_single_step_breakpoints (current_thread
);
4875 step_over_bkpt
= null_ptid
;
4876 current_thread
= saved_thread
;
4883 /* If there's a step over in progress, wait until all threads stop
4884 (that is, until the stepping thread finishes its step), and
4885 unsuspend all lwps. The stepping thread ends with its status
4886 pending, which is processed later when we get back to processing
4890 complete_ongoing_step_over (void)
4892 if (step_over_bkpt
!= null_ptid
)
4894 struct lwp_info
*lwp
;
4899 debug_printf ("detach: step over in progress, finish it first\n");
4901 /* Passing NULL_PTID as filter indicates we want all events to
4902 be left pending. Eventually this returns when there are no
4903 unwaited-for children left. */
4904 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4906 gdb_assert (ret
== -1);
4908 lwp
= find_lwp_pid (step_over_bkpt
);
4910 finish_step_over (lwp
);
4911 step_over_bkpt
= null_ptid
;
4912 unsuspend_all_lwps (lwp
);
4916 /* This function is called once per thread. We check the thread's resume
4917 request, which will tell us whether to resume, step, or leave the thread
4918 stopped; and what signal, if any, it should be sent.
4920 For threads which we aren't explicitly told otherwise, we preserve
4921 the stepping flag; this is used for stepping over gdbserver-placed
4924 If pending_flags was set in any thread, we queue any needed
4925 signals, since we won't actually resume. We already have a pending
4926 event to report, so we don't need to preserve any step requests;
4927 they should be re-issued if necessary. */
4930 linux_resume_one_thread (thread_info
*thread
, bool leave_all_stopped
)
4932 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4935 if (lwp
->resume
== NULL
)
4938 if (lwp
->resume
->kind
== resume_stop
)
4941 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4946 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4948 /* Stop the thread, and wait for the event asynchronously,
4949 through the event loop. */
4955 debug_printf ("already stopped LWP %ld\n",
4958 /* The LWP may have been stopped in an internal event that
4959 was not meant to be notified back to GDB (e.g., gdbserver
4960 breakpoint), so we should be reporting a stop event in
4963 /* If the thread already has a pending SIGSTOP, this is a
4964 no-op. Otherwise, something later will presumably resume
4965 the thread and this will cause it to cancel any pending
4966 operation, due to last_resume_kind == resume_stop. If
4967 the thread already has a pending status to report, we
4968 will still report it the next time we wait - see
4969 status_pending_p_callback. */
4971 /* If we already have a pending signal to report, then
4972 there's no need to queue a SIGSTOP, as this means we're
4973 midway through moving the LWP out of the jumppad, and we
4974 will report the pending signal as soon as that is
4976 if (lwp
->pending_signals_to_report
== NULL
)
4980 /* For stop requests, we're done. */
4982 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4986 /* If this thread which is about to be resumed has a pending status,
4987 then don't resume it - we can just report the pending status.
4988 Likewise if it is suspended, because e.g., another thread is
4989 stepping past a breakpoint. Make sure to queue any signals that
4990 would otherwise be sent. In all-stop mode, we do this decision
4991 based on if *any* thread has a pending status. If there's a
4992 thread that needs the step-over-breakpoint dance, then don't
4993 resume any other thread but that particular one. */
4994 leave_pending
= (lwp
->suspended
4995 || lwp
->status_pending_p
4996 || leave_all_stopped
);
4998 /* If we have a new signal, enqueue the signal. */
4999 if (lwp
->resume
->sig
!= 0)
5001 siginfo_t info
, *info_p
;
5003 /* If this is the same signal we were previously stopped by,
5004 make sure to queue its siginfo. */
5005 if (WIFSTOPPED (lwp
->last_status
)
5006 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
5007 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
5008 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
5013 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
5019 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
5021 proceed_one_lwp (thread
, NULL
);
5026 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
5029 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
5034 linux_resume (struct thread_resume
*resume_info
, size_t n
)
5036 struct thread_info
*need_step_over
= NULL
;
5041 debug_printf ("linux_resume:\n");
5044 for_each_thread ([&] (thread_info
*thread
)
5046 linux_set_resume_request (thread
, resume_info
, n
);
5049 /* If there is a thread which would otherwise be resumed, which has
5050 a pending status, then don't resume any threads - we can just
5051 report the pending status. Make sure to queue any signals that
5052 would otherwise be sent. In non-stop mode, we'll apply this
5053 logic to each thread individually. We consume all pending events
5054 before considering to start a step-over (in all-stop). */
5055 bool any_pending
= false;
5057 any_pending
= find_thread (resume_status_pending_p
) != NULL
;
5059 /* If there is a thread which would otherwise be resumed, which is
5060 stopped at a breakpoint that needs stepping over, then don't
5061 resume any threads - have it step over the breakpoint with all
5062 other threads stopped, then resume all threads again. Make sure
5063 to queue any signals that would otherwise be delivered or
5065 if (!any_pending
&& supports_breakpoints ())
5066 need_step_over
= find_thread (need_step_over_p
);
5068 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
5072 if (need_step_over
!= NULL
)
5073 debug_printf ("Not resuming all, need step over\n");
5074 else if (any_pending
)
5075 debug_printf ("Not resuming, all-stop and found "
5076 "an LWP with pending status\n");
5078 debug_printf ("Resuming, no pending status or step over needed\n");
5081 /* Even if we're leaving threads stopped, queue all signals we'd
5082 otherwise deliver. */
5083 for_each_thread ([&] (thread_info
*thread
)
5085 linux_resume_one_thread (thread
, leave_all_stopped
);
5089 start_step_over (get_thread_lwp (need_step_over
));
5093 debug_printf ("linux_resume done\n");
5097 /* We may have events that were pending that can/should be sent to
5098 the client now. Trigger a linux_wait call. */
5099 if (target_is_async_p ())
5103 /* This function is called once per thread. We check the thread's
5104 last resume request, which will tell us whether to resume, step, or
5105 leave the thread stopped. Any signal the client requested to be
5106 delivered has already been enqueued at this point.
5108 If any thread that GDB wants running is stopped at an internal
5109 breakpoint that needs stepping over, we start a step-over operation
5110 on that particular thread, and leave all others stopped. */
5113 proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5115 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5122 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
5127 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
5131 if (thread
->last_resume_kind
== resume_stop
5132 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
5135 debug_printf (" client wants LWP to remain %ld stopped\n",
5140 if (lwp
->status_pending_p
)
5143 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5148 gdb_assert (lwp
->suspended
>= 0);
5153 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
5157 if (thread
->last_resume_kind
== resume_stop
5158 && lwp
->pending_signals_to_report
== NULL
5159 && (lwp
->collecting_fast_tracepoint
5160 == fast_tpoint_collect_result::not_collecting
))
5162 /* We haven't reported this LWP as stopped yet (otherwise, the
5163 last_status.kind check above would catch it, and we wouldn't
5164 reach here. This LWP may have been momentarily paused by a
5165 stop_all_lwps call while handling for example, another LWP's
5166 step-over. In that case, the pending expected SIGSTOP signal
5167 that was queued at vCont;t handling time will have already
5168 been consumed by wait_for_sigstop, and so we need to requeue
5169 another one here. Note that if the LWP already has a SIGSTOP
5170 pending, this is a no-op. */
5173 debug_printf ("Client wants LWP %ld to stop. "
5174 "Making sure it has a SIGSTOP pending\n",
5180 if (thread
->last_resume_kind
== resume_step
)
5183 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5186 /* If resume_step is requested by GDB, install single-step
5187 breakpoints when the thread is about to be actually resumed if
5188 the single-step breakpoints weren't removed. */
5189 if (can_software_single_step ()
5190 && !has_single_step_breakpoints (thread
))
5191 install_software_single_step_breakpoints (lwp
);
5193 step
= maybe_hw_step (thread
);
5195 else if (lwp
->bp_reinsert
!= 0)
5198 debug_printf (" stepping LWP %ld, reinsert set\n",
5201 step
= maybe_hw_step (thread
);
5206 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
5210 unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
5212 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5217 lwp_suspended_decr (lwp
);
5219 proceed_one_lwp (thread
, except
);
5222 /* When we finish a step-over, set threads running again. If there's
5223 another thread that may need a step-over, now's the time to start
5224 it. Eventually, we'll move all threads past their breakpoints. */
5227 proceed_all_lwps (void)
5229 struct thread_info
*need_step_over
;
5231 /* If there is a thread which would otherwise be resumed, which is
5232 stopped at a breakpoint that needs stepping over, then don't
5233 resume any threads - have it step over the breakpoint with all
5234 other threads stopped, then resume all threads again. */
5236 if (supports_breakpoints ())
5238 need_step_over
= find_thread (need_step_over_p
);
5240 if (need_step_over
!= NULL
)
5243 debug_printf ("proceed_all_lwps: found "
5244 "thread %ld needing a step-over\n",
5245 lwpid_of (need_step_over
));
5247 start_step_over (get_thread_lwp (need_step_over
));
5253 debug_printf ("Proceeding, no step-over needed\n");
5255 for_each_thread ([] (thread_info
*thread
)
5257 proceed_one_lwp (thread
, NULL
);
5261 /* Stopped LWPs that the client wanted to be running, that don't have
5262 pending statuses, are set to run again, except for EXCEPT, if not
5263 NULL. This undoes a stop_all_lwps call. */
5266 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5272 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5273 lwpid_of (get_lwp_thread (except
)));
5275 debug_printf ("unstopping all lwps\n");
5279 for_each_thread ([&] (thread_info
*thread
)
5281 unsuspend_and_proceed_one_lwp (thread
, except
);
5284 for_each_thread ([&] (thread_info
*thread
)
5286 proceed_one_lwp (thread
, except
);
5291 debug_printf ("unstop_all_lwps done\n");
5297 #ifdef HAVE_LINUX_REGSETS
5299 #define use_linux_regsets 1
5301 /* Returns true if REGSET has been disabled. */
5304 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5306 return (info
->disabled_regsets
!= NULL
5307 && info
->disabled_regsets
[regset
- info
->regsets
]);
5310 /* Disable REGSET. */
5313 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5317 dr_offset
= regset
- info
->regsets
;
5318 if (info
->disabled_regsets
== NULL
)
5319 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5320 info
->disabled_regsets
[dr_offset
] = 1;
5324 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5325 struct regcache
*regcache
)
5327 struct regset_info
*regset
;
5328 int saw_general_regs
= 0;
5332 pid
= lwpid_of (current_thread
);
5333 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5338 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5341 buf
= xmalloc (regset
->size
);
5343 nt_type
= regset
->nt_type
;
5347 iov
.iov_len
= regset
->size
;
5348 data
= (void *) &iov
;
5354 res
= ptrace (regset
->get_request
, pid
,
5355 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5357 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5363 /* If we get EIO on a regset, do not try it again for
5364 this process mode. */
5365 disable_regset (regsets_info
, regset
);
5367 else if (errno
== ENODATA
)
5369 /* ENODATA may be returned if the regset is currently
5370 not "active". This can happen in normal operation,
5371 so suppress the warning in this case. */
5373 else if (errno
== ESRCH
)
5375 /* At this point, ESRCH should mean the process is
5376 already gone, in which case we simply ignore attempts
5377 to read its registers. */
5382 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5389 if (regset
->type
== GENERAL_REGS
)
5390 saw_general_regs
= 1;
5391 regset
->store_function (regcache
, buf
);
5395 if (saw_general_regs
)
5402 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5403 struct regcache
*regcache
)
5405 struct regset_info
*regset
;
5406 int saw_general_regs
= 0;
5410 pid
= lwpid_of (current_thread
);
5411 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5416 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5417 || regset
->fill_function
== NULL
)
5420 buf
= xmalloc (regset
->size
);
5422 /* First fill the buffer with the current register set contents,
5423 in case there are any items in the kernel's regset that are
5424 not in gdbserver's regcache. */
5426 nt_type
= regset
->nt_type
;
5430 iov
.iov_len
= regset
->size
;
5431 data
= (void *) &iov
;
5437 res
= ptrace (regset
->get_request
, pid
,
5438 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5440 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5445 /* Then overlay our cached registers on that. */
5446 regset
->fill_function (regcache
, buf
);
5448 /* Only now do we write the register set. */
5450 res
= ptrace (regset
->set_request
, pid
,
5451 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5453 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5461 /* If we get EIO on a regset, do not try it again for
5462 this process mode. */
5463 disable_regset (regsets_info
, regset
);
5465 else if (errno
== ESRCH
)
5467 /* At this point, ESRCH should mean the process is
5468 already gone, in which case we simply ignore attempts
5469 to change its registers. See also the related
5470 comment in linux_resume_one_lwp. */
5476 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5479 else if (regset
->type
== GENERAL_REGS
)
5480 saw_general_regs
= 1;
5483 if (saw_general_regs
)
5489 #else /* !HAVE_LINUX_REGSETS */
5491 #define use_linux_regsets 0
5492 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5493 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5497 /* Return 1 if register REGNO is supported by one of the regset ptrace
5498 calls or 0 if it has to be transferred individually. */
5501 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5503 unsigned char mask
= 1 << (regno
% 8);
5504 size_t index
= regno
/ 8;
5506 return (use_linux_regsets
5507 && (regs_info
->regset_bitmap
== NULL
5508 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5511 #ifdef HAVE_LINUX_USRREGS
5514 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5518 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5519 error ("Invalid register number %d.", regnum
);
5521 addr
= usrregs
->regmap
[regnum
];
5526 /* Fetch one register. */
5528 fetch_register (const struct usrregs_info
*usrregs
,
5529 struct regcache
*regcache
, int regno
)
5536 if (regno
>= usrregs
->num_regs
)
5538 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5541 regaddr
= register_addr (usrregs
, regno
);
5545 size
= ((register_size (regcache
->tdesc
, regno
)
5546 + sizeof (PTRACE_XFER_TYPE
) - 1)
5547 & -sizeof (PTRACE_XFER_TYPE
));
5548 buf
= (char *) alloca (size
);
5550 pid
= lwpid_of (current_thread
);
5551 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5554 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5555 ptrace (PTRACE_PEEKUSER
, pid
,
5556 /* Coerce to a uintptr_t first to avoid potential gcc warning
5557 of coercing an 8 byte integer to a 4 byte pointer. */
5558 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5559 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5562 /* Mark register REGNO unavailable. */
5563 supply_register (regcache
, regno
, NULL
);
5568 if (the_low_target
.supply_ptrace_register
)
5569 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5571 supply_register (regcache
, regno
, buf
);
5574 /* Store one register. */
5576 store_register (const struct usrregs_info
*usrregs
,
5577 struct regcache
*regcache
, int regno
)
5584 if (regno
>= usrregs
->num_regs
)
5586 if ((*the_low_target
.cannot_store_register
) (regno
))
5589 regaddr
= register_addr (usrregs
, regno
);
5593 size
= ((register_size (regcache
->tdesc
, regno
)
5594 + sizeof (PTRACE_XFER_TYPE
) - 1)
5595 & -sizeof (PTRACE_XFER_TYPE
));
5596 buf
= (char *) alloca (size
);
5597 memset (buf
, 0, size
);
5599 if (the_low_target
.collect_ptrace_register
)
5600 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5602 collect_register (regcache
, regno
, buf
);
5604 pid
= lwpid_of (current_thread
);
5605 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5608 ptrace (PTRACE_POKEUSER
, pid
,
5609 /* Coerce to a uintptr_t first to avoid potential gcc warning
5610 about coercing an 8 byte integer to a 4 byte pointer. */
5611 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5612 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5615 /* At this point, ESRCH should mean the process is
5616 already gone, in which case we simply ignore attempts
5617 to change its registers. See also the related
5618 comment in linux_resume_one_lwp. */
5622 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5623 error ("writing register %d: %s", regno
, strerror (errno
));
5625 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5629 /* Fetch all registers, or just one, from the child process.
5630 If REGNO is -1, do this for all registers, skipping any that are
5631 assumed to have been retrieved by regsets_fetch_inferior_registers,
5632 unless ALL is non-zero.
5633 Otherwise, REGNO specifies which register (so we can save time). */
5635 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5636 struct regcache
*regcache
, int regno
, int all
)
5638 struct usrregs_info
*usr
= regs_info
->usrregs
;
5642 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5643 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5644 fetch_register (usr
, regcache
, regno
);
5647 fetch_register (usr
, regcache
, regno
);
5650 /* Store our register values back into the inferior.
5651 If REGNO is -1, do this for all registers, skipping any that are
5652 assumed to have been saved by regsets_store_inferior_registers,
5653 unless ALL is non-zero.
5654 Otherwise, REGNO specifies which register (so we can save time). */
5656 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5657 struct regcache
*regcache
, int regno
, int all
)
5659 struct usrregs_info
*usr
= regs_info
->usrregs
;
5663 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5664 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5665 store_register (usr
, regcache
, regno
);
5668 store_register (usr
, regcache
, regno
);
5671 #else /* !HAVE_LINUX_USRREGS */
5673 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5674 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5680 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5684 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5688 if (the_low_target
.fetch_register
!= NULL
5689 && regs_info
->usrregs
!= NULL
)
5690 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5691 (*the_low_target
.fetch_register
) (regcache
, regno
);
5693 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5694 if (regs_info
->usrregs
!= NULL
)
5695 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5699 if (the_low_target
.fetch_register
!= NULL
5700 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5703 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5705 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5707 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5708 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5713 linux_store_registers (struct regcache
*regcache
, int regno
)
5717 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5721 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5723 if (regs_info
->usrregs
!= NULL
)
5724 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5728 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5730 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5732 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5733 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5738 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5739 to debugger memory starting at MYADDR. */
5742 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5744 int pid
= lwpid_of (current_thread
);
5745 PTRACE_XFER_TYPE
*buffer
;
5753 /* Try using /proc. Don't bother for one word. */
5754 if (len
>= 3 * sizeof (long))
5758 /* We could keep this file open and cache it - possibly one per
5759 thread. That requires some juggling, but is even faster. */
5760 sprintf (filename
, "/proc/%d/mem", pid
);
5761 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5765 /* If pread64 is available, use it. It's faster if the kernel
5766 supports it (only one syscall), and it's 64-bit safe even on
5767 32-bit platforms (for instance, SPARC debugging a SPARC64
5770 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5773 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5774 bytes
= read (fd
, myaddr
, len
);
5781 /* Some data was read, we'll try to get the rest with ptrace. */
5791 /* Round starting address down to longword boundary. */
5792 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5793 /* Round ending address up; get number of longwords that makes. */
5794 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5795 / sizeof (PTRACE_XFER_TYPE
));
5796 /* Allocate buffer of that many longwords. */
5797 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5799 /* Read all the longwords */
5801 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5803 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5804 about coercing an 8 byte integer to a 4 byte pointer. */
5805 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5806 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5807 (PTRACE_TYPE_ARG4
) 0);
5813 /* Copy appropriate bytes out of the buffer. */
5816 i
*= sizeof (PTRACE_XFER_TYPE
);
5817 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5819 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5826 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5827 memory at MEMADDR. On failure (cannot write to the inferior)
5828 returns the value of errno. Always succeeds if LEN is zero. */
5831 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5834 /* Round starting address down to longword boundary. */
5835 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5836 /* Round ending address up; get number of longwords that makes. */
5838 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5839 / sizeof (PTRACE_XFER_TYPE
);
5841 /* Allocate buffer of that many longwords. */
5842 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5844 int pid
= lwpid_of (current_thread
);
5848 /* Zero length write always succeeds. */
5854 /* Dump up to four bytes. */
5855 char str
[4 * 2 + 1];
5857 int dump
= len
< 4 ? len
: 4;
5859 for (i
= 0; i
< dump
; i
++)
5861 sprintf (p
, "%02x", myaddr
[i
]);
5866 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5867 str
, (long) memaddr
, pid
);
5870 /* Fill start and end extra bytes of buffer with existing memory data. */
5873 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5874 about coercing an 8 byte integer to a 4 byte pointer. */
5875 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5876 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5877 (PTRACE_TYPE_ARG4
) 0);
5885 = ptrace (PTRACE_PEEKTEXT
, pid
,
5886 /* Coerce to a uintptr_t first to avoid potential gcc warning
5887 about coercing an 8 byte integer to a 4 byte pointer. */
5888 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5889 * sizeof (PTRACE_XFER_TYPE
)),
5890 (PTRACE_TYPE_ARG4
) 0);
5895 /* Copy data to be written over corresponding part of buffer. */
5897 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5900 /* Write the entire buffer. */
5902 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5905 ptrace (PTRACE_POKETEXT
, pid
,
5906 /* Coerce to a uintptr_t first to avoid potential gcc warning
5907 about coercing an 8 byte integer to a 4 byte pointer. */
5908 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5909 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5918 linux_look_up_symbols (void)
5920 #ifdef USE_THREAD_DB
5921 struct process_info
*proc
= current_process ();
5923 if (proc
->priv
->thread_db
!= NULL
)
5931 linux_request_interrupt (void)
5933 /* Send a SIGINT to the process group. This acts just like the user
5934 typed a ^C on the controlling terminal. */
5935 kill (-signal_pid
, SIGINT
);
5938 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5939 to debugger memory starting at MYADDR. */
5942 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5944 char filename
[PATH_MAX
];
5946 int pid
= lwpid_of (current_thread
);
5948 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5950 fd
= open (filename
, O_RDONLY
);
5954 if (offset
!= (CORE_ADDR
) 0
5955 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5958 n
= read (fd
, myaddr
, len
);
5965 /* These breakpoint and watchpoint related wrapper functions simply
5966 pass on the function call if the target has registered a
5967 corresponding function. */
5970 linux_supports_z_point_type (char z_type
)
5972 return (the_low_target
.supports_z_point_type
!= NULL
5973 && the_low_target
.supports_z_point_type (z_type
));
5977 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5978 int size
, struct raw_breakpoint
*bp
)
5980 if (type
== raw_bkpt_type_sw
)
5981 return insert_memory_breakpoint (bp
);
5982 else if (the_low_target
.insert_point
!= NULL
)
5983 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5985 /* Unsupported (see target.h). */
5990 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5991 int size
, struct raw_breakpoint
*bp
)
5993 if (type
== raw_bkpt_type_sw
)
5994 return remove_memory_breakpoint (bp
);
5995 else if (the_low_target
.remove_point
!= NULL
)
5996 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5998 /* Unsupported (see target.h). */
6002 /* Implement the to_stopped_by_sw_breakpoint target_ops
6006 linux_stopped_by_sw_breakpoint (void)
6008 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6010 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
6013 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6017 linux_supports_stopped_by_sw_breakpoint (void)
6019 return USE_SIGTRAP_SIGINFO
;
6022 /* Implement the to_stopped_by_hw_breakpoint target_ops
6026 linux_stopped_by_hw_breakpoint (void)
6028 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6030 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
6033 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6037 linux_supports_stopped_by_hw_breakpoint (void)
6039 return USE_SIGTRAP_SIGINFO
;
6042 /* Implement the supports_hardware_single_step target_ops method. */
6045 linux_supports_hardware_single_step (void)
6047 return can_hardware_single_step ();
6051 linux_supports_software_single_step (void)
6053 return can_software_single_step ();
6057 linux_stopped_by_watchpoint (void)
6059 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6061 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
6065 linux_stopped_data_address (void)
6067 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
6069 return lwp
->stopped_data_address
;
6072 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6073 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6074 && defined(PT_TEXT_END_ADDR)
6076 /* This is only used for targets that define PT_TEXT_ADDR,
6077 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6078 the target has different ways of acquiring this information, like
6081 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6082 to tell gdb about. */
6085 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
6087 unsigned long text
, text_end
, data
;
6088 int pid
= lwpid_of (current_thread
);
6092 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
6093 (PTRACE_TYPE_ARG4
) 0);
6094 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
6095 (PTRACE_TYPE_ARG4
) 0);
6096 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
6097 (PTRACE_TYPE_ARG4
) 0);
6101 /* Both text and data offsets produced at compile-time (and so
6102 used by gdb) are relative to the beginning of the program,
6103 with the data segment immediately following the text segment.
6104 However, the actual runtime layout in memory may put the data
6105 somewhere else, so when we send gdb a data base-address, we
6106 use the real data base address and subtract the compile-time
6107 data base-address from it (which is just the length of the
6108 text segment). BSS immediately follows data in both
6111 *data_p
= data
- (text_end
- text
);
6120 linux_qxfer_osdata (const char *annex
,
6121 unsigned char *readbuf
, unsigned const char *writebuf
,
6122 CORE_ADDR offset
, int len
)
6124 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
6127 /* Convert a native/host siginfo object, into/from the siginfo in the
6128 layout of the inferiors' architecture. */
6131 siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
, int direction
)
6135 if (the_low_target
.siginfo_fixup
!= NULL
)
6136 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
6138 /* If there was no callback, or the callback didn't do anything,
6139 then just do a straight memcpy. */
6143 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
6145 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
6150 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
6151 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
6155 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6157 if (current_thread
== NULL
)
6160 pid
= lwpid_of (current_thread
);
6163 debug_printf ("%s siginfo for lwp %d.\n",
6164 readbuf
!= NULL
? "Reading" : "Writing",
6167 if (offset
>= sizeof (siginfo
))
6170 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6173 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6174 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6175 inferior with a 64-bit GDBSERVER should look the same as debugging it
6176 with a 32-bit GDBSERVER, we need to convert it. */
6177 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6179 if (offset
+ len
> sizeof (siginfo
))
6180 len
= sizeof (siginfo
) - offset
;
6182 if (readbuf
!= NULL
)
6183 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6186 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6188 /* Convert back to ptrace layout before flushing it out. */
6189 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6191 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6198 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6199 so we notice when children change state; as the handler for the
6200 sigsuspend in my_waitpid. */
6203 sigchld_handler (int signo
)
6205 int old_errno
= errno
;
6211 /* fprintf is not async-signal-safe, so call write
6213 if (write (2, "sigchld_handler\n",
6214 sizeof ("sigchld_handler\n") - 1) < 0)
6215 break; /* just ignore */
6219 if (target_is_async_p ())
6220 async_file_mark (); /* trigger a linux_wait */
6226 linux_supports_non_stop (void)
6232 linux_async (int enable
)
6234 int previous
= target_is_async_p ();
6237 debug_printf ("linux_async (%d), previous=%d\n",
6240 if (previous
!= enable
)
6243 sigemptyset (&mask
);
6244 sigaddset (&mask
, SIGCHLD
);
6246 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
6250 if (pipe (linux_event_pipe
) == -1)
6252 linux_event_pipe
[0] = -1;
6253 linux_event_pipe
[1] = -1;
6254 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6256 warning ("creating event pipe failed.");
6260 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6261 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6263 /* Register the event loop handler. */
6264 add_file_handler (linux_event_pipe
[0],
6265 handle_target_event
, NULL
);
6267 /* Always trigger a linux_wait. */
6272 delete_file_handler (linux_event_pipe
[0]);
6274 close (linux_event_pipe
[0]);
6275 close (linux_event_pipe
[1]);
6276 linux_event_pipe
[0] = -1;
6277 linux_event_pipe
[1] = -1;
6280 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6287 linux_start_non_stop (int nonstop
)
6289 /* Register or unregister from event-loop accordingly. */
6290 linux_async (nonstop
);
6292 if (target_is_async_p () != (nonstop
!= 0))
6299 linux_supports_multi_process (void)
6304 /* Check if fork events are supported. */
6307 linux_supports_fork_events (void)
6309 return linux_supports_tracefork ();
6312 /* Check if vfork events are supported. */
6315 linux_supports_vfork_events (void)
6317 return linux_supports_tracefork ();
6320 /* Check if exec events are supported. */
6323 linux_supports_exec_events (void)
6325 return linux_supports_traceexec ();
6328 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6329 ptrace flags for all inferiors. This is in case the new GDB connection
6330 doesn't support the same set of events that the previous one did. */
6333 linux_handle_new_gdb_connection (void)
6335 /* Request that all the lwps reset their ptrace options. */
6336 for_each_thread ([] (thread_info
*thread
)
6338 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6342 /* Stop the lwp so we can modify its ptrace options. */
6343 lwp
->must_set_ptrace_flags
= 1;
6344 linux_stop_lwp (lwp
);
6348 /* Already stopped; go ahead and set the ptrace options. */
6349 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6350 int options
= linux_low_ptrace_options (proc
->attached
);
6352 linux_enable_event_reporting (lwpid_of (thread
), options
);
6353 lwp
->must_set_ptrace_flags
= 0;
6359 linux_supports_disable_randomization (void)
6361 #ifdef HAVE_PERSONALITY
6369 linux_supports_agent (void)
6375 linux_supports_range_stepping (void)
6377 if (can_software_single_step ())
6379 if (*the_low_target
.supports_range_stepping
== NULL
)
6382 return (*the_low_target
.supports_range_stepping
) ();
6385 /* Enumerate spufs IDs for process PID. */
6387 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6393 struct dirent
*entry
;
6395 sprintf (path
, "/proc/%ld/fd", pid
);
6396 dir
= opendir (path
);
6401 while ((entry
= readdir (dir
)) != NULL
)
6407 fd
= atoi (entry
->d_name
);
6411 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6412 if (stat (path
, &st
) != 0)
6414 if (!S_ISDIR (st
.st_mode
))
6417 if (statfs (path
, &stfs
) != 0)
6419 if (stfs
.f_type
!= SPUFS_MAGIC
)
6422 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6424 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6434 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6435 object type, using the /proc file system. */
6437 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6438 unsigned const char *writebuf
,
6439 CORE_ADDR offset
, int len
)
6441 long pid
= lwpid_of (current_thread
);
6446 if (!writebuf
&& !readbuf
)
6454 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6457 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6458 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6463 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6470 ret
= write (fd
, writebuf
, (size_t) len
);
6472 ret
= read (fd
, readbuf
, (size_t) len
);
6478 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6479 struct target_loadseg
6481 /* Core address to which the segment is mapped. */
6483 /* VMA recorded in the program header. */
6485 /* Size of this segment in memory. */
6489 # if defined PT_GETDSBT
6490 struct target_loadmap
6492 /* Protocol version number, must be zero. */
6494 /* Pointer to the DSBT table, its size, and the DSBT index. */
6495 unsigned *dsbt_table
;
6496 unsigned dsbt_size
, dsbt_index
;
6497 /* Number of segments in this map. */
6499 /* The actual memory map. */
6500 struct target_loadseg segs
[/*nsegs*/];
6502 # define LINUX_LOADMAP PT_GETDSBT
6503 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6504 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6506 struct target_loadmap
6508 /* Protocol version number, must be zero. */
6510 /* Number of segments in this map. */
6512 /* The actual memory map. */
6513 struct target_loadseg segs
[/*nsegs*/];
6515 # define LINUX_LOADMAP PTRACE_GETFDPIC
6516 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6517 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6521 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6522 unsigned char *myaddr
, unsigned int len
)
6524 int pid
= lwpid_of (current_thread
);
6526 struct target_loadmap
*data
= NULL
;
6527 unsigned int actual_length
, copy_length
;
6529 if (strcmp (annex
, "exec") == 0)
6530 addr
= (int) LINUX_LOADMAP_EXEC
;
6531 else if (strcmp (annex
, "interp") == 0)
6532 addr
= (int) LINUX_LOADMAP_INTERP
;
6536 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6542 actual_length
= sizeof (struct target_loadmap
)
6543 + sizeof (struct target_loadseg
) * data
->nsegs
;
6545 if (offset
< 0 || offset
> actual_length
)
6548 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6549 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6553 # define linux_read_loadmap NULL
6554 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6557 linux_process_qsupported (char **features
, int count
)
6559 if (the_low_target
.process_qsupported
!= NULL
)
6560 the_low_target
.process_qsupported (features
, count
);
6564 linux_supports_catch_syscall (void)
6566 return (the_low_target
.get_syscall_trapinfo
!= NULL
6567 && linux_supports_tracesysgood ());
6571 linux_get_ipa_tdesc_idx (void)
6573 if (the_low_target
.get_ipa_tdesc_idx
== NULL
)
6576 return (*the_low_target
.get_ipa_tdesc_idx
) ();
6580 linux_supports_tracepoints (void)
6582 if (*the_low_target
.supports_tracepoints
== NULL
)
6585 return (*the_low_target
.supports_tracepoints
) ();
6589 linux_read_pc (struct regcache
*regcache
)
6591 if (the_low_target
.get_pc
== NULL
)
6594 return (*the_low_target
.get_pc
) (regcache
);
6598 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6600 gdb_assert (the_low_target
.set_pc
!= NULL
);
6602 (*the_low_target
.set_pc
) (regcache
, pc
);
6606 linux_thread_stopped (struct thread_info
*thread
)
6608 return get_thread_lwp (thread
)->stopped
;
6611 /* This exposes stop-all-threads functionality to other modules. */
6614 linux_pause_all (int freeze
)
6616 stop_all_lwps (freeze
, NULL
);
6619 /* This exposes unstop-all-threads functionality to other gdbserver
6623 linux_unpause_all (int unfreeze
)
6625 unstop_all_lwps (unfreeze
, NULL
);
6629 linux_prepare_to_access_memory (void)
6631 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6634 linux_pause_all (1);
6639 linux_done_accessing_memory (void)
6641 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6644 linux_unpause_all (1);
6648 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6649 CORE_ADDR collector
,
6652 CORE_ADDR
*jump_entry
,
6653 CORE_ADDR
*trampoline
,
6654 ULONGEST
*trampoline_size
,
6655 unsigned char *jjump_pad_insn
,
6656 ULONGEST
*jjump_pad_insn_size
,
6657 CORE_ADDR
*adjusted_insn_addr
,
6658 CORE_ADDR
*adjusted_insn_addr_end
,
6661 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6662 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6663 jump_entry
, trampoline
, trampoline_size
,
6664 jjump_pad_insn
, jjump_pad_insn_size
,
6665 adjusted_insn_addr
, adjusted_insn_addr_end
,
6669 static struct emit_ops
*
6670 linux_emit_ops (void)
6672 if (the_low_target
.emit_ops
!= NULL
)
6673 return (*the_low_target
.emit_ops
) ();
6679 linux_get_min_fast_tracepoint_insn_len (void)
6681 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6684 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6687 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6688 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6690 char filename
[PATH_MAX
];
6692 const int auxv_size
= is_elf64
6693 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6694 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6696 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6698 fd
= open (filename
, O_RDONLY
);
6704 while (read (fd
, buf
, auxv_size
) == auxv_size
6705 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6709 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6711 switch (aux
->a_type
)
6714 *phdr_memaddr
= aux
->a_un
.a_val
;
6717 *num_phdr
= aux
->a_un
.a_val
;
6723 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6725 switch (aux
->a_type
)
6728 *phdr_memaddr
= aux
->a_un
.a_val
;
6731 *num_phdr
= aux
->a_un
.a_val
;
6739 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6741 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6742 "phdr_memaddr = %ld, phdr_num = %d",
6743 (long) *phdr_memaddr
, *num_phdr
);
6750 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6753 get_dynamic (const int pid
, const int is_elf64
)
6755 CORE_ADDR phdr_memaddr
, relocation
;
6757 unsigned char *phdr_buf
;
6758 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6760 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6763 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6764 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6766 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6769 /* Compute relocation: it is expected to be 0 for "regular" executables,
6770 non-zero for PIE ones. */
6772 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6775 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6777 if (p
->p_type
== PT_PHDR
)
6778 relocation
= phdr_memaddr
- p
->p_vaddr
;
6782 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6784 if (p
->p_type
== PT_PHDR
)
6785 relocation
= phdr_memaddr
- p
->p_vaddr
;
6788 if (relocation
== -1)
6790 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6791 any real world executables, including PIE executables, have always
6792 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6793 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6794 or present DT_DEBUG anyway (fpc binaries are statically linked).
6796 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6798 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6803 for (i
= 0; i
< num_phdr
; i
++)
6807 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6809 if (p
->p_type
== PT_DYNAMIC
)
6810 return p
->p_vaddr
+ relocation
;
6814 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6816 if (p
->p_type
== PT_DYNAMIC
)
6817 return p
->p_vaddr
+ relocation
;
6824 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6825 can be 0 if the inferior does not yet have the library list initialized.
6826 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6827 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6830 get_r_debug (const int pid
, const int is_elf64
)
6832 CORE_ADDR dynamic_memaddr
;
6833 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6834 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6837 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6838 if (dynamic_memaddr
== 0)
6841 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6845 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6846 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6850 unsigned char buf
[sizeof (Elf64_Xword
)];
6854 #ifdef DT_MIPS_RLD_MAP
6855 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6857 if (linux_read_memory (dyn
->d_un
.d_val
,
6858 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6863 #endif /* DT_MIPS_RLD_MAP */
6864 #ifdef DT_MIPS_RLD_MAP_REL
6865 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6867 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6868 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6873 #endif /* DT_MIPS_RLD_MAP_REL */
6875 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6876 map
= dyn
->d_un
.d_val
;
6878 if (dyn
->d_tag
== DT_NULL
)
6883 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6884 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6888 unsigned char buf
[sizeof (Elf32_Word
)];
6892 #ifdef DT_MIPS_RLD_MAP
6893 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6895 if (linux_read_memory (dyn
->d_un
.d_val
,
6896 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6901 #endif /* DT_MIPS_RLD_MAP */
6902 #ifdef DT_MIPS_RLD_MAP_REL
6903 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6905 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6906 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6911 #endif /* DT_MIPS_RLD_MAP_REL */
6913 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6914 map
= dyn
->d_un
.d_val
;
6916 if (dyn
->d_tag
== DT_NULL
)
6920 dynamic_memaddr
+= dyn_size
;
6926 /* Read one pointer from MEMADDR in the inferior. */
6929 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6933 /* Go through a union so this works on either big or little endian
6934 hosts, when the inferior's pointer size is smaller than the size
6935 of CORE_ADDR. It is assumed the inferior's endianness is the
6936 same of the superior's. */
6939 CORE_ADDR core_addr
;
6944 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6947 if (ptr_size
== sizeof (CORE_ADDR
))
6948 *ptr
= addr
.core_addr
;
6949 else if (ptr_size
== sizeof (unsigned int))
6952 gdb_assert_not_reached ("unhandled pointer size");
6957 struct link_map_offsets
6959 /* Offset and size of r_debug.r_version. */
6960 int r_version_offset
;
6962 /* Offset and size of r_debug.r_map. */
6965 /* Offset to l_addr field in struct link_map. */
6968 /* Offset to l_name field in struct link_map. */
6971 /* Offset to l_ld field in struct link_map. */
6974 /* Offset to l_next field in struct link_map. */
6977 /* Offset to l_prev field in struct link_map. */
6981 /* Construct qXfer:libraries-svr4:read reply. */
6984 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6985 unsigned const char *writebuf
,
6986 CORE_ADDR offset
, int len
)
6988 struct process_info_private
*const priv
= current_process ()->priv
;
6989 char filename
[PATH_MAX
];
6992 static const struct link_map_offsets lmo_32bit_offsets
=
6994 0, /* r_version offset. */
6995 4, /* r_debug.r_map offset. */
6996 0, /* l_addr offset in link_map. */
6997 4, /* l_name offset in link_map. */
6998 8, /* l_ld offset in link_map. */
6999 12, /* l_next offset in link_map. */
7000 16 /* l_prev offset in link_map. */
7003 static const struct link_map_offsets lmo_64bit_offsets
=
7005 0, /* r_version offset. */
7006 8, /* r_debug.r_map offset. */
7007 0, /* l_addr offset in link_map. */
7008 8, /* l_name offset in link_map. */
7009 16, /* l_ld offset in link_map. */
7010 24, /* l_next offset in link_map. */
7011 32 /* l_prev offset in link_map. */
7013 const struct link_map_offsets
*lmo
;
7014 unsigned int machine
;
7016 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
7017 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
7018 int header_done
= 0;
7020 if (writebuf
!= NULL
)
7022 if (readbuf
== NULL
)
7025 pid
= lwpid_of (current_thread
);
7026 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
7027 is_elf64
= elf_64_file_p (filename
, &machine
);
7028 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
7029 ptr_size
= is_elf64
? 8 : 4;
7031 while (annex
[0] != '\0')
7037 sep
= strchr (annex
, '=');
7041 name_len
= sep
- annex
;
7042 if (name_len
== 5 && startswith (annex
, "start"))
7044 else if (name_len
== 4 && startswith (annex
, "prev"))
7048 annex
= strchr (sep
, ';');
7055 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
7062 if (priv
->r_debug
== 0)
7063 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
7065 /* We failed to find DT_DEBUG. Such situation will not change
7066 for this inferior - do not retry it. Report it to GDB as
7067 E01, see for the reasons at the GDB solib-svr4.c side. */
7068 if (priv
->r_debug
== (CORE_ADDR
) -1)
7071 if (priv
->r_debug
!= 0)
7073 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
7074 (unsigned char *) &r_version
,
7075 sizeof (r_version
)) != 0
7078 warning ("unexpected r_debug version %d", r_version
);
7080 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
7081 &lm_addr
, ptr_size
) != 0)
7083 warning ("unable to read r_map from 0x%lx",
7084 (long) priv
->r_debug
+ lmo
->r_map_offset
);
7089 std::string document
= "<library-list-svr4 version=\"1.0\"";
7092 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
7093 &l_name
, ptr_size
) == 0
7094 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
7095 &l_addr
, ptr_size
) == 0
7096 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
7097 &l_ld
, ptr_size
) == 0
7098 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
7099 &l_prev
, ptr_size
) == 0
7100 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
7101 &l_next
, ptr_size
) == 0)
7103 unsigned char libname
[PATH_MAX
];
7105 if (lm_prev
!= l_prev
)
7107 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7108 (long) lm_prev
, (long) l_prev
);
7112 /* Ignore the first entry even if it has valid name as the first entry
7113 corresponds to the main executable. The first entry should not be
7114 skipped if the dynamic loader was loaded late by a static executable
7115 (see solib-svr4.c parameter ignore_first). But in such case the main
7116 executable does not have PT_DYNAMIC present and this function already
7117 exited above due to failed get_r_debug. */
7119 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
7122 /* Not checking for error because reading may stop before
7123 we've got PATH_MAX worth of characters. */
7125 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
7126 libname
[sizeof (libname
) - 1] = '\0';
7127 if (libname
[0] != '\0')
7131 /* Terminate `<library-list-svr4'. */
7136 string_appendf (document
, "<library name=\"");
7137 xml_escape_text_append (&document
, (char *) libname
);
7138 string_appendf (document
, "\" lm=\"0x%lx\" "
7139 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7140 (unsigned long) lm_addr
, (unsigned long) l_addr
,
7141 (unsigned long) l_ld
);
7151 /* Empty list; terminate `<library-list-svr4'. */
7155 document
+= "</library-list-svr4>";
7157 int document_len
= document
.length ();
7158 if (offset
< document_len
)
7159 document_len
-= offset
;
7162 if (len
> document_len
)
7165 memcpy (readbuf
, document
.data () + offset
, len
);
7170 #ifdef HAVE_LINUX_BTRACE
7172 /* See to_disable_btrace target method. */
7175 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
7177 enum btrace_error err
;
7179 err
= linux_disable_btrace (tinfo
);
7180 return (err
== BTRACE_ERR_NONE
? 0 : -1);
7183 /* Encode an Intel Processor Trace configuration. */
7186 linux_low_encode_pt_config (struct buffer
*buffer
,
7187 const struct btrace_data_pt_config
*config
)
7189 buffer_grow_str (buffer
, "<pt-config>\n");
7191 switch (config
->cpu
.vendor
)
7194 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7195 "model=\"%u\" stepping=\"%u\"/>\n",
7196 config
->cpu
.family
, config
->cpu
.model
,
7197 config
->cpu
.stepping
);
7204 buffer_grow_str (buffer
, "</pt-config>\n");
7207 /* Encode a raw buffer. */
7210 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
7216 /* We use hex encoding - see common/rsp-low.h. */
7217 buffer_grow_str (buffer
, "<raw>\n");
7223 elem
[0] = tohex ((*data
>> 4) & 0xf);
7224 elem
[1] = tohex (*data
++ & 0xf);
7226 buffer_grow (buffer
, elem
, 2);
7229 buffer_grow_str (buffer
, "</raw>\n");
7232 /* See to_read_btrace target method. */
7235 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
7236 enum btrace_read_type type
)
7238 struct btrace_data btrace
;
7239 struct btrace_block
*block
;
7240 enum btrace_error err
;
7243 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7244 if (err
!= BTRACE_ERR_NONE
)
7246 if (err
== BTRACE_ERR_OVERFLOW
)
7247 buffer_grow_str0 (buffer
, "E.Overflow.");
7249 buffer_grow_str0 (buffer
, "E.Generic Error.");
7254 switch (btrace
.format
)
7256 case BTRACE_FORMAT_NONE
:
7257 buffer_grow_str0 (buffer
, "E.No Trace.");
7260 case BTRACE_FORMAT_BTS
:
7261 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7262 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7265 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7267 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7268 paddress (block
->begin
), paddress (block
->end
));
7270 buffer_grow_str0 (buffer
, "</btrace>\n");
7273 case BTRACE_FORMAT_PT
:
7274 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7275 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7276 buffer_grow_str (buffer
, "<pt>\n");
7278 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7280 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7281 btrace
.variant
.pt
.size
);
7283 buffer_grow_str (buffer
, "</pt>\n");
7284 buffer_grow_str0 (buffer
, "</btrace>\n");
7288 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7295 /* See to_btrace_conf target method. */
7298 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7299 struct buffer
*buffer
)
7301 const struct btrace_config
*conf
;
7303 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7304 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7306 conf
= linux_btrace_conf (tinfo
);
7309 switch (conf
->format
)
7311 case BTRACE_FORMAT_NONE
:
7314 case BTRACE_FORMAT_BTS
:
7315 buffer_xml_printf (buffer
, "<bts");
7316 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7317 buffer_xml_printf (buffer
, " />\n");
7320 case BTRACE_FORMAT_PT
:
7321 buffer_xml_printf (buffer
, "<pt");
7322 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7323 buffer_xml_printf (buffer
, "/>\n");
7328 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7331 #endif /* HAVE_LINUX_BTRACE */
7333 /* See nat/linux-nat.h. */
7336 current_lwp_ptid (void)
7338 return ptid_of (current_thread
);
7341 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7344 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7346 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7347 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7349 return default_breakpoint_kind_from_pc (pcptr
);
7352 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7354 static const gdb_byte
*
7355 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7357 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7359 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7362 /* Implementation of the target_ops method
7363 "breakpoint_kind_from_current_state". */
7366 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7368 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7369 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7371 return linux_breakpoint_kind_from_pc (pcptr
);
7374 /* Default implementation of linux_target_ops method "set_pc" for
7375 32-bit pc register which is literally named "pc". */
7378 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7380 uint32_t newpc
= pc
;
7382 supply_register_by_name (regcache
, "pc", &newpc
);
7385 /* Default implementation of linux_target_ops method "get_pc" for
7386 32-bit pc register which is literally named "pc". */
7389 linux_get_pc_32bit (struct regcache
*regcache
)
7393 collect_register_by_name (regcache
, "pc", &pc
);
7395 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7399 /* Default implementation of linux_target_ops method "set_pc" for
7400 64-bit pc register which is literally named "pc". */
7403 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7405 uint64_t newpc
= pc
;
7407 supply_register_by_name (regcache
, "pc", &newpc
);
7410 /* Default implementation of linux_target_ops method "get_pc" for
7411 64-bit pc register which is literally named "pc". */
7414 linux_get_pc_64bit (struct regcache
*regcache
)
7418 collect_register_by_name (regcache
, "pc", &pc
);
7420 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7425 static struct target_ops linux_target_ops
= {
7426 linux_create_inferior
,
7427 linux_post_create_inferior
,
7436 linux_fetch_registers
,
7437 linux_store_registers
,
7438 linux_prepare_to_access_memory
,
7439 linux_done_accessing_memory
,
7442 linux_look_up_symbols
,
7443 linux_request_interrupt
,
7445 linux_supports_z_point_type
,
7448 linux_stopped_by_sw_breakpoint
,
7449 linux_supports_stopped_by_sw_breakpoint
,
7450 linux_stopped_by_hw_breakpoint
,
7451 linux_supports_stopped_by_hw_breakpoint
,
7452 linux_supports_hardware_single_step
,
7453 linux_stopped_by_watchpoint
,
7454 linux_stopped_data_address
,
7455 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7456 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7457 && defined(PT_TEXT_END_ADDR)
7462 #ifdef USE_THREAD_DB
7463 thread_db_get_tls_address
,
7468 hostio_last_error_from_errno
,
7471 linux_supports_non_stop
,
7473 linux_start_non_stop
,
7474 linux_supports_multi_process
,
7475 linux_supports_fork_events
,
7476 linux_supports_vfork_events
,
7477 linux_supports_exec_events
,
7478 linux_handle_new_gdb_connection
,
7479 #ifdef USE_THREAD_DB
7480 thread_db_handle_monitor_command
,
7484 linux_common_core_of_thread
,
7486 linux_process_qsupported
,
7487 linux_supports_tracepoints
,
7490 linux_thread_stopped
,
7494 linux_stabilize_threads
,
7495 linux_install_fast_tracepoint_jump_pad
,
7497 linux_supports_disable_randomization
,
7498 linux_get_min_fast_tracepoint_insn_len
,
7499 linux_qxfer_libraries_svr4
,
7500 linux_supports_agent
,
7501 #ifdef HAVE_LINUX_BTRACE
7502 linux_enable_btrace
,
7503 linux_low_disable_btrace
,
7504 linux_low_read_btrace
,
7505 linux_low_btrace_conf
,
7512 linux_supports_range_stepping
,
7513 linux_proc_pid_to_exec_file
,
7514 linux_mntns_open_cloexec
,
7516 linux_mntns_readlink
,
7517 linux_breakpoint_kind_from_pc
,
7518 linux_sw_breakpoint_from_kind
,
7519 linux_proc_tid_get_name
,
7520 linux_breakpoint_kind_from_current_state
,
7521 linux_supports_software_single_step
,
7522 linux_supports_catch_syscall
,
7523 linux_get_ipa_tdesc_idx
,
7525 thread_db_thread_handle
,
7531 #ifdef HAVE_LINUX_REGSETS
7533 initialize_regsets_info (struct regsets_info
*info
)
7535 for (info
->num_regsets
= 0;
7536 info
->regsets
[info
->num_regsets
].size
>= 0;
7537 info
->num_regsets
++)
7543 initialize_low (void)
7545 struct sigaction sigchld_action
;
7547 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7548 set_target_ops (&linux_target_ops
);
7550 linux_ptrace_init_warnings ();
7551 linux_proc_init_warnings ();
7553 sigchld_action
.sa_handler
= sigchld_handler
;
7554 sigemptyset (&sigchld_action
.sa_mask
);
7555 sigchld_action
.sa_flags
= SA_RESTART
;
7556 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7558 initialize_low_arch ();
7560 linux_check_ptrace_features ();