2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
5 * Pentium III FXSR, SSE support
6 * Gareth Hughes <gareth@valinux.com>, May 2000
10 * Handle hardware traps and faults.
12 #include <linux/interrupt.h>
13 #include <linux/kallsyms.h>
14 #include <linux/spinlock.h>
15 #include <linux/kprobes.h>
16 #include <linux/uaccess.h>
17 #include <linux/utsname.h>
18 #include <linux/kdebug.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/ptrace.h>
22 #include <linux/string.h>
23 #include <linux/unwind.h>
24 #include <linux/delay.h>
25 #include <linux/errno.h>
26 #include <linux/kexec.h>
27 #include <linux/sched.h>
28 #include <linux/timer.h>
29 #include <linux/init.h>
30 #include <linux/bug.h>
31 #include <linux/nmi.h>
33 #include <linux/smp.h>
37 #include <linux/ioport.h>
38 #include <linux/eisa.h>
42 #include <linux/mca.h>
45 #if defined(CONFIG_EDAC)
46 #include <linux/edac.h>
49 #include <asm/stacktrace.h>
50 #include <asm/processor.h>
51 #include <asm/debugreg.h>
52 #include <asm/atomic.h>
53 #include <asm/system.h>
54 #include <asm/unwind.h>
55 #include <asm/traps.h>
59 #include <mach_traps.h>
62 #include <asm/pgalloc.h>
63 #include <asm/proto.h>
66 #include <asm/processor-flags.h>
67 #include <asm/arch_hooks.h>
72 #include "cpu/mcheck/mce.h"
74 DECLARE_BITMAP(used_vectors
, NR_VECTORS
);
75 EXPORT_SYMBOL_GPL(used_vectors
);
77 asmlinkage
int system_call(void);
79 /* Do we ignore FPU interrupts ? */
83 * The IDT has to be page-aligned to simplify the Pentium
84 * F0 0F bug workaround.. We have a special link segment
87 gate_desc idt_table
[256]
88 __attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
91 static int ignore_nmis
;
93 static inline void conditional_sti(struct pt_regs
*regs
)
95 if (regs
->flags
& X86_EFLAGS_IF
)
99 static inline void preempt_conditional_sti(struct pt_regs
*regs
)
102 if (regs
->flags
& X86_EFLAGS_IF
)
106 static inline void preempt_conditional_cli(struct pt_regs
*regs
)
108 if (regs
->flags
& X86_EFLAGS_IF
)
115 die_if_kernel(const char *str
, struct pt_regs
*regs
, long err
)
117 if (!user_mode_vm(regs
))
122 * Perform the lazy TSS's I/O bitmap copy. If the TSS has an
123 * invalid offset set (the LAZY one) and the faulting thread has
124 * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS,
125 * we set the offset field correctly and return 1.
127 static int lazy_iobitmap_copy(void)
129 struct thread_struct
*thread
;
130 struct tss_struct
*tss
;
134 tss
= &per_cpu(init_tss
, cpu
);
135 thread
= ¤t
->thread
;
137 if (tss
->x86_tss
.io_bitmap_base
== INVALID_IO_BITMAP_OFFSET_LAZY
&&
138 thread
->io_bitmap_ptr
) {
139 memcpy(tss
->io_bitmap
, thread
->io_bitmap_ptr
,
140 thread
->io_bitmap_max
);
142 * If the previously set map was extending to higher ports
143 * than the current one, pad extra space with 0xff (no access).
145 if (thread
->io_bitmap_max
< tss
->io_bitmap_max
) {
146 memset((char *) tss
->io_bitmap
+
147 thread
->io_bitmap_max
, 0xff,
148 tss
->io_bitmap_max
- thread
->io_bitmap_max
);
150 tss
->io_bitmap_max
= thread
->io_bitmap_max
;
151 tss
->x86_tss
.io_bitmap_base
= IO_BITMAP_OFFSET
;
152 tss
->io_bitmap_owner
= thread
;
163 static void __kprobes
164 do_trap(int trapnr
, int signr
, char *str
, struct pt_regs
*regs
,
165 long error_code
, siginfo_t
*info
)
167 struct task_struct
*tsk
= current
;
170 if (regs
->flags
& X86_VM_MASK
) {
172 * traps 0, 1, 3, 4, and 5 should be forwarded to vm86.
173 * On nmi (interrupt 2), do_trap should not be called.
181 if (!user_mode(regs
))
188 * We want error_code and trap_no set for userspace faults and
189 * kernelspace faults which result in die(), but not
190 * kernelspace faults which are fixed up. die() gives the
191 * process no chance to handle the signal and notice the
192 * kernel fault information, so that won't result in polluting
193 * the information about previously queued, but not yet
194 * delivered, faults. See also do_general_protection below.
196 tsk
->thread
.error_code
= error_code
;
197 tsk
->thread
.trap_no
= trapnr
;
200 if (show_unhandled_signals
&& unhandled_signal(tsk
, signr
) &&
201 printk_ratelimit()) {
203 "%s[%d] trap %s ip:%lx sp:%lx error:%lx",
204 tsk
->comm
, tsk
->pid
, str
,
205 regs
->ip
, regs
->sp
, error_code
);
206 print_vma_addr(" in ", regs
->ip
);
212 force_sig_info(signr
, info
, tsk
);
214 force_sig(signr
, tsk
);
218 if (!fixup_exception(regs
)) {
219 tsk
->thread
.error_code
= error_code
;
220 tsk
->thread
.trap_no
= trapnr
;
221 die(str
, regs
, error_code
);
227 if (handle_vm86_trap((struct kernel_vm86_regs
*) regs
,
234 #define DO_ERROR(trapnr, signr, str, name) \
235 dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
237 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
240 conditional_sti(regs); \
241 do_trap(trapnr, signr, str, regs, error_code, NULL); \
244 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
245 dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
248 info.si_signo = signr; \
250 info.si_code = sicode; \
251 info.si_addr = (void __user *)siaddr; \
252 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
255 conditional_sti(regs); \
256 do_trap(trapnr, signr, str, regs, error_code, &info); \
259 DO_ERROR_INFO(0, SIGFPE
, "divide error", divide_error
, FPE_INTDIV
, regs
->ip
)
260 DO_ERROR(4, SIGSEGV
, "overflow", overflow
)
261 DO_ERROR(5, SIGSEGV
, "bounds", bounds
)
262 DO_ERROR_INFO(6, SIGILL
, "invalid opcode", invalid_op
, ILL_ILLOPN
, regs
->ip
)
263 DO_ERROR(9, SIGFPE
, "coprocessor segment overrun", coprocessor_segment_overrun
)
264 DO_ERROR(10, SIGSEGV
, "invalid TSS", invalid_TSS
)
265 DO_ERROR(11, SIGBUS
, "segment not present", segment_not_present
)
267 DO_ERROR(12, SIGBUS
, "stack segment", stack_segment
)
269 DO_ERROR_INFO(17, SIGBUS
, "alignment check", alignment_check
, BUS_ADRALN
, 0)
272 /* Runs on IST stack */
273 dotraplinkage
void do_stack_segment(struct pt_regs
*regs
, long error_code
)
275 if (notify_die(DIE_TRAP
, "stack segment", regs
, error_code
,
276 12, SIGBUS
) == NOTIFY_STOP
)
278 preempt_conditional_sti(regs
);
279 do_trap(12, SIGBUS
, "stack segment", regs
, error_code
, NULL
);
280 preempt_conditional_cli(regs
);
283 dotraplinkage
void do_double_fault(struct pt_regs
*regs
, long error_code
)
285 static const char str
[] = "double fault";
286 struct task_struct
*tsk
= current
;
288 /* Return not checked because double check cannot be ignored */
289 notify_die(DIE_TRAP
, str
, regs
, error_code
, 8, SIGSEGV
);
291 tsk
->thread
.error_code
= error_code
;
292 tsk
->thread
.trap_no
= 8;
294 /* This is always a kernel trap and never fixable (and thus must
297 die(str
, regs
, error_code
);
301 dotraplinkage
void __kprobes
302 do_general_protection(struct pt_regs
*regs
, long error_code
)
304 struct task_struct
*tsk
;
306 conditional_sti(regs
);
309 if (lazy_iobitmap_copy()) {
310 /* restart the faulting instruction */
314 if (regs
->flags
& X86_VM_MASK
)
319 if (!user_mode(regs
))
322 tsk
->thread
.error_code
= error_code
;
323 tsk
->thread
.trap_no
= 13;
325 if (show_unhandled_signals
&& unhandled_signal(tsk
, SIGSEGV
) &&
326 printk_ratelimit()) {
328 "%s[%d] general protection ip:%lx sp:%lx error:%lx",
329 tsk
->comm
, task_pid_nr(tsk
),
330 regs
->ip
, regs
->sp
, error_code
);
331 print_vma_addr(" in ", regs
->ip
);
335 force_sig(SIGSEGV
, tsk
);
341 handle_vm86_fault((struct kernel_vm86_regs
*) regs
, error_code
);
346 if (fixup_exception(regs
))
349 tsk
->thread
.error_code
= error_code
;
350 tsk
->thread
.trap_no
= 13;
351 if (notify_die(DIE_GPF
, "general protection fault", regs
,
352 error_code
, 13, SIGSEGV
) == NOTIFY_STOP
)
354 die("general protection fault", regs
, error_code
);
357 static notrace __kprobes
void
358 mem_parity_error(unsigned char reason
, struct pt_regs
*regs
)
361 "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
362 reason
, smp_processor_id());
365 "You have some hardware problem, likely on the PCI bus.\n");
367 #if defined(CONFIG_EDAC)
368 if (edac_handler_set()) {
369 edac_atomic_assert_error();
374 if (panic_on_unrecovered_nmi
)
375 panic("NMI: Not continuing");
377 printk(KERN_EMERG
"Dazed and confused, but trying to continue\n");
379 /* Clear and disable the memory parity error line. */
380 reason
= (reason
& 0xf) | 4;
384 static notrace __kprobes
void
385 io_check_error(unsigned char reason
, struct pt_regs
*regs
)
389 printk(KERN_EMERG
"NMI: IOCK error (debug interrupt?)\n");
390 show_registers(regs
);
392 /* Re-enable the IOCK line, wait for a few seconds */
393 reason
= (reason
& 0xf) | 8;
404 static notrace __kprobes
void
405 unknown_nmi_error(unsigned char reason
, struct pt_regs
*regs
)
407 if (notify_die(DIE_NMIUNKNOWN
, "nmi", regs
, reason
, 2, SIGINT
) ==
412 * Might actually be able to figure out what the guilty party
421 "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
422 reason
, smp_processor_id());
424 printk(KERN_EMERG
"Do you have a strange power saving mode enabled?\n");
425 if (panic_on_unrecovered_nmi
)
426 panic("NMI: Not continuing");
428 printk(KERN_EMERG
"Dazed and confused, but trying to continue\n");
432 static DEFINE_SPINLOCK(nmi_print_lock
);
434 void notrace __kprobes
die_nmi(char *str
, struct pt_regs
*regs
, int do_panic
)
436 if (notify_die(DIE_NMIWATCHDOG
, str
, regs
, 0, 2, SIGINT
) == NOTIFY_STOP
)
439 spin_lock(&nmi_print_lock
);
441 * We are in trouble anyway, lets at least try
442 * to get a message out:
445 printk(KERN_EMERG
"%s", str
);
446 printk(" on CPU%d, ip %08lx, registers:\n",
447 smp_processor_id(), regs
->ip
);
448 show_registers(regs
);
450 panic("Non maskable interrupt");
452 spin_unlock(&nmi_print_lock
);
456 * If we are in kernel we are probably nested up pretty bad
457 * and might aswell get out now while we still can:
459 if (!user_mode_vm(regs
)) {
460 current
->thread
.trap_no
= 2;
468 static notrace __kprobes
void default_do_nmi(struct pt_regs
*regs
)
470 unsigned char reason
= 0;
473 cpu
= smp_processor_id();
475 /* Only the BSP gets external NMIs from the system. */
477 reason
= get_nmi_reason();
479 if (!(reason
& 0xc0)) {
480 if (notify_die(DIE_NMI_IPI
, "nmi_ipi", regs
, reason
, 2, SIGINT
)
483 #ifdef CONFIG_X86_LOCAL_APIC
485 * Ok, so this is none of the documented NMI sources,
486 * so it must be the NMI watchdog.
488 if (nmi_watchdog_tick(regs
, reason
))
490 if (!do_nmi_callback(regs
, cpu
))
491 unknown_nmi_error(reason
, regs
);
493 unknown_nmi_error(reason
, regs
);
498 if (notify_die(DIE_NMI
, "nmi", regs
, reason
, 2, SIGINT
) == NOTIFY_STOP
)
501 /* AK: following checks seem to be broken on modern chipsets. FIXME */
503 mem_parity_error(reason
, regs
);
505 io_check_error(reason
, regs
);
508 * Reassert NMI in case it became active meanwhile
509 * as it's edge-triggered:
515 dotraplinkage notrace __kprobes
void
516 do_nmi(struct pt_regs
*regs
, long error_code
)
521 { int cpu
; cpu
= smp_processor_id(); ++nmi_count(cpu
); }
523 add_pda(__nmi_count
, 1);
527 default_do_nmi(regs
);
538 void restart_nmi(void)
544 /* May run on IST stack. */
545 dotraplinkage
void __kprobes
do_int3(struct pt_regs
*regs
, long error_code
)
547 #ifdef CONFIG_KPROBES
548 if (notify_die(DIE_INT3
, "int3", regs
, error_code
, 3, SIGTRAP
)
552 if (notify_die(DIE_TRAP
, "int3", regs
, error_code
, 3, SIGTRAP
)
557 preempt_conditional_sti(regs
);
558 do_trap(3, SIGTRAP
, "int3", regs
, error_code
, NULL
);
559 preempt_conditional_cli(regs
);
563 /* Help handler running on IST stack to switch back to user stack
564 for scheduling or signal handling. The actual stack switch is done in
566 asmlinkage __kprobes
struct pt_regs
*sync_regs(struct pt_regs
*eregs
)
568 struct pt_regs
*regs
= eregs
;
569 /* Did already sync */
570 if (eregs
== (struct pt_regs
*)eregs
->sp
)
572 /* Exception from user space */
573 else if (user_mode(eregs
))
574 regs
= task_pt_regs(current
);
575 /* Exception from kernel and interrupts are enabled. Move to
576 kernel process stack. */
577 else if (eregs
->flags
& X86_EFLAGS_IF
)
578 regs
= (struct pt_regs
*)(eregs
->sp
-= sizeof(struct pt_regs
));
586 * Our handling of the processor debug registers is non-trivial.
587 * We do not clear them on entry and exit from the kernel. Therefore
588 * it is possible to get a watchpoint trap here from inside the kernel.
589 * However, the code in ./ptrace.c has ensured that the user can
590 * only set watchpoints on userspace addresses. Therefore the in-kernel
591 * watchpoint trap can only occur in code which is reading/writing
592 * from user space. Such code must not hold kernel locks (since it
593 * can equally take a page fault), therefore it is safe to call
594 * force_sig_info even though that claims and releases locks.
596 * Code in ./signal.c ensures that the debug control register
597 * is restored before we deliver any signal, and therefore that
598 * user code runs with the correct debug control register even though
601 * Being careful here means that we don't have to be as careful in a
602 * lot of more complicated places (task switching can be a bit lazy
603 * about restoring all the debug state, and ptrace doesn't have to
604 * find every occurrence of the TF bit that could be saved away even
607 * May run on IST stack.
609 dotraplinkage
void __kprobes
do_debug(struct pt_regs
*regs
, long error_code
)
611 struct task_struct
*tsk
= current
;
612 unsigned long condition
;
615 get_debugreg(condition
, 6);
618 * The processor cleared BTF, so don't mark that we need it set.
620 clear_tsk_thread_flag(tsk
, TIF_DEBUGCTLMSR
);
621 tsk
->thread
.debugctlmsr
= 0;
623 if (notify_die(DIE_DEBUG
, "debug", regs
, condition
, error_code
,
624 SIGTRAP
) == NOTIFY_STOP
)
627 /* It's safe to allow irq's after DR6 has been saved */
628 preempt_conditional_sti(regs
);
630 /* Mask out spurious debug traps due to lazy DR7 setting */
631 if (condition
& (DR_TRAP0
|DR_TRAP1
|DR_TRAP2
|DR_TRAP3
)) {
632 if (!tsk
->thread
.debugreg7
)
637 if (regs
->flags
& X86_VM_MASK
)
641 /* Save debug status register where ptrace can see it */
642 tsk
->thread
.debugreg6
= condition
;
645 * Single-stepping through TF: make sure we ignore any events in
646 * kernel space (but re-enable TF when returning to user mode).
648 if (condition
& DR_STEP
) {
649 if (!user_mode(regs
))
650 goto clear_TF_reenable
;
653 si_code
= get_si_code(condition
);
654 /* Ok, finally something we can handle */
655 send_sigtrap(tsk
, regs
, error_code
, si_code
);
658 * Disable additional traps. They'll be re-enabled when
659 * the signal is delivered.
663 preempt_conditional_cli(regs
);
668 handle_vm86_trap((struct kernel_vm86_regs
*) regs
, error_code
, 1);
669 preempt_conditional_cli(regs
);
674 set_tsk_thread_flag(tsk
, TIF_SINGLESTEP
);
675 regs
->flags
&= ~X86_EFLAGS_TF
;
676 preempt_conditional_cli(regs
);
681 static int kernel_math_error(struct pt_regs
*regs
, const char *str
, int trapnr
)
683 if (fixup_exception(regs
))
686 notify_die(DIE_GPF
, str
, regs
, 0, trapnr
, SIGFPE
);
687 /* Illegal floating point operation in the kernel */
688 current
->thread
.trap_no
= trapnr
;
695 * Note that we play around with the 'TS' bit in an attempt to get
696 * the correct behaviour even in the presence of the asynchronous
699 void math_error(void __user
*ip
)
701 struct task_struct
*task
;
703 unsigned short cwd
, swd
;
706 * Save the info for the exception handler and clear the error.
710 task
->thread
.trap_no
= 16;
711 task
->thread
.error_code
= 0;
712 info
.si_signo
= SIGFPE
;
714 info
.si_code
= __SI_FAULT
;
717 * (~cwd & swd) will mask out exceptions that are not set to unmasked
718 * status. 0x3f is the exception bits in these regs, 0x200 is the
719 * C1 reg you need in case of a stack fault, 0x040 is the stack
720 * fault bit. We should only be taking one exception at a time,
721 * so if this combination doesn't produce any single exception,
722 * then we have a bad program that isn't synchronizing its FPU usage
723 * and it will suffer the consequences since we won't be able to
724 * fully reproduce the context of the exception
726 cwd
= get_fpu_cwd(task
);
727 swd
= get_fpu_swd(task
);
728 switch (swd
& ~cwd
& 0x3f) {
729 case 0x000: /* No unmasked exception */
733 default: /* Multiple exceptions */
735 case 0x001: /* Invalid Op */
737 * swd & 0x240 == 0x040: Stack Underflow
738 * swd & 0x240 == 0x240: Stack Overflow
739 * User must clear the SF bit (0x40) if set
741 info
.si_code
= FPE_FLTINV
;
743 case 0x002: /* Denormalize */
744 case 0x010: /* Underflow */
745 info
.si_code
= FPE_FLTUND
;
747 case 0x004: /* Zero Divide */
748 info
.si_code
= FPE_FLTDIV
;
750 case 0x008: /* Overflow */
751 info
.si_code
= FPE_FLTOVF
;
753 case 0x020: /* Precision */
754 info
.si_code
= FPE_FLTRES
;
757 force_sig_info(SIGFPE
, &info
, task
);
760 dotraplinkage
void do_coprocessor_error(struct pt_regs
*regs
, long error_code
)
762 conditional_sti(regs
);
767 if (!user_mode(regs
) &&
768 kernel_math_error(regs
, "kernel x87 math error", 16))
772 math_error((void __user
*)regs
->ip
);
775 static void simd_math_error(void __user
*ip
)
777 struct task_struct
*task
;
779 unsigned short mxcsr
;
782 * Save the info for the exception handler and clear the error.
786 task
->thread
.trap_no
= 19;
787 task
->thread
.error_code
= 0;
788 info
.si_signo
= SIGFPE
;
790 info
.si_code
= __SI_FAULT
;
793 * The SIMD FPU exceptions are handled a little differently, as there
794 * is only a single status/control register. Thus, to determine which
795 * unmasked exception was caught we must mask the exception mask bits
796 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
798 mxcsr
= get_fpu_mxcsr(task
);
799 switch (~((mxcsr
& 0x1f80) >> 7) & (mxcsr
& 0x3f)) {
803 case 0x001: /* Invalid Op */
804 info
.si_code
= FPE_FLTINV
;
806 case 0x002: /* Denormalize */
807 case 0x010: /* Underflow */
808 info
.si_code
= FPE_FLTUND
;
810 case 0x004: /* Zero Divide */
811 info
.si_code
= FPE_FLTDIV
;
813 case 0x008: /* Overflow */
814 info
.si_code
= FPE_FLTOVF
;
816 case 0x020: /* Precision */
817 info
.si_code
= FPE_FLTRES
;
820 force_sig_info(SIGFPE
, &info
, task
);
824 do_simd_coprocessor_error(struct pt_regs
*regs
, long error_code
)
826 conditional_sti(regs
);
830 /* Handle SIMD FPU exceptions on PIII+ processors. */
832 simd_math_error((void __user
*)regs
->ip
);
836 * Handle strange cache flush from user space exception
837 * in all other cases. This is undocumented behaviour.
839 if (regs
->flags
& X86_VM_MASK
) {
840 handle_vm86_fault((struct kernel_vm86_regs
*)regs
, error_code
);
843 current
->thread
.trap_no
= 19;
844 current
->thread
.error_code
= error_code
;
845 die_if_kernel("cache flush denied", regs
, error_code
);
846 force_sig(SIGSEGV
, current
);
848 if (!user_mode(regs
) &&
849 kernel_math_error(regs
, "kernel simd math error", 19))
851 simd_math_error((void __user
*)regs
->ip
);
856 do_spurious_interrupt_bug(struct pt_regs
*regs
, long error_code
)
858 conditional_sti(regs
);
860 /* No need to warn about this any longer. */
861 printk(KERN_INFO
"Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
866 unsigned long patch_espfix_desc(unsigned long uesp
, unsigned long kesp
)
868 struct desc_struct
*gdt
= get_cpu_gdt_table(smp_processor_id());
869 unsigned long base
= (kesp
- uesp
) & -THREAD_SIZE
;
870 unsigned long new_kesp
= kesp
- base
;
871 unsigned long lim_pages
= (new_kesp
| (THREAD_SIZE
- 1)) >> PAGE_SHIFT
;
872 __u64 desc
= *(__u64
*)&gdt
[GDT_ENTRY_ESPFIX_SS
];
874 /* Set up base for espfix segment */
875 desc
&= 0x00f0ff0000000000ULL
;
876 desc
|= ((((__u64
)base
) << 16) & 0x000000ffffff0000ULL
) |
877 ((((__u64
)base
) << 32) & 0xff00000000000000ULL
) |
878 ((((__u64
)lim_pages
) << 32) & 0x000f000000000000ULL
) |
879 (lim_pages
& 0xffff);
880 *(__u64
*)&gdt
[GDT_ENTRY_ESPFIX_SS
] = desc
;
885 asmlinkage
void __attribute__((weak
)) smp_thermal_interrupt(void)
889 asmlinkage
void __attribute__((weak
)) mce_threshold_interrupt(void)
895 * 'math_state_restore()' saves the current math information in the
896 * old math state array, and gets the new ones from the current task
898 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
899 * Don't touch unless you *really* know how it works.
901 * Must be called with kernel preemption disabled (in this case,
902 * local interrupts are disabled at the call-site in entry.S).
904 asmlinkage
void math_state_restore(void)
906 struct thread_info
*thread
= current_thread_info();
907 struct task_struct
*tsk
= thread
->task
;
909 if (!tsk_used_math(tsk
)) {
912 * does a slab alloc which can sleep
918 do_group_exit(SIGKILL
);
924 clts(); /* Allow maths ops (or we recurse) */
929 * Paranoid restore. send a SIGSEGV if we fail to restore the state.
931 if (unlikely(restore_fpu_checking(tsk
))) {
933 force_sig(SIGSEGV
, tsk
);
937 thread
->status
|= TS_USEDFPU
; /* So we fnsave on switch_to() */
940 EXPORT_SYMBOL_GPL(math_state_restore
);
942 #ifndef CONFIG_MATH_EMULATION
943 asmlinkage
void math_emulate(long arg
)
946 "math-emulation not enabled and no coprocessor found.\n");
947 printk(KERN_EMERG
"killing %s.\n", current
->comm
);
948 force_sig(SIGFPE
, current
);
951 #endif /* CONFIG_MATH_EMULATION */
953 dotraplinkage
void __kprobes
954 do_device_not_available(struct pt_regs
*regs
, long error
)
957 if (read_cr0() & X86_CR0_EM
) {
958 conditional_sti(regs
);
961 math_state_restore(); /* interrupts still off */
962 conditional_sti(regs
);
965 math_state_restore();
970 #ifdef CONFIG_X86_MCE
971 dotraplinkage
void __kprobes
do_machine_check(struct pt_regs
*regs
, long error
)
973 conditional_sti(regs
);
974 machine_check_vector(regs
, error
);
978 dotraplinkage
void do_iret_error(struct pt_regs
*regs
, long error_code
)
983 info
.si_signo
= SIGILL
;
985 info
.si_code
= ILL_BADSTK
;
987 if (notify_die(DIE_TRAP
, "iret exception",
988 regs
, error_code
, 32, SIGILL
) == NOTIFY_STOP
)
990 do_trap(32, SIGILL
, "iret exception", regs
, error_code
, &info
);
994 void __init
trap_init(void)
1001 void __iomem
*p
= early_ioremap(0x0FFFD9, 4);
1003 if (readl(p
) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24))
1005 early_iounmap(p
, 4);
1008 set_intr_gate(0, ÷_error
);
1009 set_intr_gate_ist(1, &debug
, DEBUG_STACK
);
1010 set_intr_gate_ist(2, &nmi
, NMI_STACK
);
1011 /* int3 can be called from all */
1012 set_system_intr_gate_ist(3, &int3
, DEBUG_STACK
);
1013 /* int4 can be called from all */
1014 set_system_intr_gate(4, &overflow
);
1015 set_intr_gate(5, &bounds
);
1016 set_intr_gate(6, &invalid_op
);
1017 set_intr_gate(7, &device_not_available
);
1018 #ifdef CONFIG_X86_32
1019 set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS
);
1021 set_intr_gate_ist(8, &double_fault
, DOUBLEFAULT_STACK
);
1023 set_intr_gate(9, &coprocessor_segment_overrun
);
1024 set_intr_gate(10, &invalid_TSS
);
1025 set_intr_gate(11, &segment_not_present
);
1026 set_intr_gate_ist(12, &stack_segment
, STACKFAULT_STACK
);
1027 set_intr_gate(13, &general_protection
);
1028 set_intr_gate(14, &page_fault
);
1029 set_intr_gate(15, &spurious_interrupt_bug
);
1030 set_intr_gate(16, &coprocessor_error
);
1031 set_intr_gate(17, &alignment_check
);
1032 #ifdef CONFIG_X86_MCE
1033 set_intr_gate_ist(18, &machine_check
, MCE_STACK
);
1035 set_intr_gate(19, &simd_coprocessor_error
);
1037 #ifdef CONFIG_IA32_EMULATION
1038 set_system_intr_gate(IA32_SYSCALL_VECTOR
, ia32_syscall
);
1041 #ifdef CONFIG_X86_32
1043 printk(KERN_INFO
"Enabling fast FPU save and restore... ");
1044 set_in_cr4(X86_CR4_OSFXSR
);
1049 "Enabling unmasked SIMD FPU exception support... ");
1050 set_in_cr4(X86_CR4_OSXMMEXCPT
);
1054 set_system_trap_gate(SYSCALL_VECTOR
, &system_call
);
1056 /* Reserve all the builtin and the syscall vector: */
1057 for (i
= 0; i
< FIRST_EXTERNAL_VECTOR
; i
++)
1058 set_bit(i
, used_vectors
);
1060 set_bit(SYSCALL_VECTOR
, used_vectors
);
1063 * Should be a barrier for any external CPU state:
1067 #ifdef CONFIG_X86_32