2 * linux/arch/x86-64/traps.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
7 * Pentium III FXSR, SSE support
8 * Gareth Hughes <gareth@valinux.com>, May 2000
12 * 'Traps.c' handles hardware traps and faults after we have saved some
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/ptrace.h>
20 #include <linux/timer.h>
22 #include <linux/init.h>
23 #include <linux/delay.h>
24 #include <linux/spinlock.h>
25 #include <linux/interrupt.h>
26 #include <linux/kallsyms.h>
27 #include <linux/module.h>
28 #include <linux/moduleparam.h>
29 #include <linux/nmi.h>
30 #include <linux/kprobes.h>
31 #include <linux/kexec.h>
32 #include <linux/unwind.h>
33 #include <linux/uaccess.h>
34 #include <linux/bug.h>
35 #include <linux/kdebug.h>
37 #include <asm/system.h>
39 #include <asm/atomic.h>
40 #include <asm/debugreg.h>
43 #include <asm/processor.h>
44 #include <asm/unwind.h>
46 #include <asm/pgalloc.h>
48 #include <asm/proto.h>
50 #include <asm/stacktrace.h>
52 asmlinkage
void divide_error(void);
53 asmlinkage
void debug(void);
54 asmlinkage
void nmi(void);
55 asmlinkage
void int3(void);
56 asmlinkage
void overflow(void);
57 asmlinkage
void bounds(void);
58 asmlinkage
void invalid_op(void);
59 asmlinkage
void device_not_available(void);
60 asmlinkage
void double_fault(void);
61 asmlinkage
void coprocessor_segment_overrun(void);
62 asmlinkage
void invalid_TSS(void);
63 asmlinkage
void segment_not_present(void);
64 asmlinkage
void stack_segment(void);
65 asmlinkage
void general_protection(void);
66 asmlinkage
void page_fault(void);
67 asmlinkage
void coprocessor_error(void);
68 asmlinkage
void simd_coprocessor_error(void);
69 asmlinkage
void reserved(void);
70 asmlinkage
void alignment_check(void);
71 asmlinkage
void machine_check(void);
72 asmlinkage
void spurious_interrupt_bug(void);
74 static inline void conditional_sti(struct pt_regs
*regs
)
76 if (regs
->eflags
& X86_EFLAGS_IF
)
80 static inline void preempt_conditional_sti(struct pt_regs
*regs
)
83 if (regs
->eflags
& X86_EFLAGS_IF
)
87 static inline void preempt_conditional_cli(struct pt_regs
*regs
)
89 if (regs
->eflags
& X86_EFLAGS_IF
)
91 /* Make sure to not schedule here because we could be running
92 on an exception stack. */
93 preempt_enable_no_resched();
96 int kstack_depth_to_print
= 12;
98 #ifdef CONFIG_KALLSYMS
99 void printk_address(unsigned long address
)
101 unsigned long offset
= 0, symsize
;
107 symname
= kallsyms_lookup(address
, &symsize
, &offset
,
110 printk(" [<%016lx>]\n", address
);
114 modname
= delim
= "";
115 printk(" [<%016lx>] %s%s%s%s+0x%lx/0x%lx\n",
116 address
, delim
, modname
, delim
, symname
, offset
, symsize
);
119 void printk_address(unsigned long address
)
121 printk(" [<%016lx>]\n", address
);
125 static unsigned long *in_exception_stack(unsigned cpu
, unsigned long stack
,
126 unsigned *usedp
, char **idp
)
128 static char ids
[][8] = {
129 [DEBUG_STACK
- 1] = "#DB",
130 [NMI_STACK
- 1] = "NMI",
131 [DOUBLEFAULT_STACK
- 1] = "#DF",
132 [STACKFAULT_STACK
- 1] = "#SS",
133 [MCE_STACK
- 1] = "#MC",
134 #if DEBUG_STKSZ > EXCEPTION_STKSZ
135 [N_EXCEPTION_STACKS
... N_EXCEPTION_STACKS
+ DEBUG_STKSZ
/ EXCEPTION_STKSZ
- 2] = "#DB[?]"
141 * Iterate over all exception stacks, and figure out whether
142 * 'stack' is in one of them:
144 for (k
= 0; k
< N_EXCEPTION_STACKS
; k
++) {
145 unsigned long end
= per_cpu(orig_ist
, cpu
).ist
[k
];
147 * Is 'stack' above this exception frame's end?
148 * If yes then skip to the next frame.
153 * Is 'stack' above this exception frame's start address?
154 * If yes then we found the right frame.
156 if (stack
>= end
- EXCEPTION_STKSZ
) {
158 * Make sure we only iterate through an exception
159 * stack once. If it comes up for the second time
160 * then there's something wrong going on - just
161 * break out and return NULL:
163 if (*usedp
& (1U << k
))
167 return (unsigned long *)end
;
170 * If this is a debug stack, and if it has a larger size than
171 * the usual exception stacks, then 'stack' might still
172 * be within the lower portion of the debug stack:
174 #if DEBUG_STKSZ > EXCEPTION_STKSZ
175 if (k
== DEBUG_STACK
- 1 && stack
>= end
- DEBUG_STKSZ
) {
176 unsigned j
= N_EXCEPTION_STACKS
- 1;
179 * Black magic. A large debug stack is composed of
180 * multiple exception stack entries, which we
181 * iterate through now. Dont look:
185 end
-= EXCEPTION_STKSZ
;
186 ids
[j
][4] = '1' + (j
- N_EXCEPTION_STACKS
);
187 } while (stack
< end
- EXCEPTION_STKSZ
);
188 if (*usedp
& (1U << j
))
192 return (unsigned long *)end
;
199 #define MSG(txt) ops->warning(data, txt)
202 * x86-64 can have upto three kernel stacks:
205 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
208 static inline int valid_stack_ptr(struct thread_info
*tinfo
, void *p
)
210 void *t
= (void *)tinfo
;
211 return p
> t
&& p
< t
+ THREAD_SIZE
- 3;
214 void dump_trace(struct task_struct
*tsk
, struct pt_regs
*regs
,
215 unsigned long *stack
,
216 struct stacktrace_ops
*ops
, void *data
)
218 const unsigned cpu
= get_cpu();
219 unsigned long *irqstack_end
= (unsigned long*)cpu_pda(cpu
)->irqstackptr
;
221 struct thread_info
*tinfo
;
229 if (tsk
&& tsk
!= current
)
230 stack
= (unsigned long *)tsk
->thread
.rsp
;
234 * Print function call entries within a stack. 'cond' is the
235 * "end of stackframe" condition, that the 'stack++'
236 * iteration will eventually trigger.
238 #define HANDLE_STACK(cond) \
240 unsigned long addr = *stack++; \
241 /* Use unlocked access here because except for NMIs \
242 we should be already protected against module unloads */ \
243 if (__kernel_text_address(addr)) { \
245 * If the address is either in the text segment of the \
246 * kernel, or in the region which contains vmalloc'ed \
247 * memory, it *may* be the address of a calling \
248 * routine; if so, print it so that someone tracing \
249 * down the cause of the crash will be able to figure \
250 * out the call path that was taken. \
252 ops->address(data, addr); \
257 * Print function call entries in all stacks, starting at the
258 * current stack address. If the stacks consist of nested
263 unsigned long *estack_end
;
264 estack_end
= in_exception_stack(cpu
, (unsigned long)stack
,
268 if (ops
->stack(data
, id
) < 0)
270 HANDLE_STACK (stack
< estack_end
);
271 ops
->stack(data
, "<EOE>");
273 * We link to the next stack via the
274 * second-to-last pointer (index -2 to end) in the
277 stack
= (unsigned long *) estack_end
[-2];
281 unsigned long *irqstack
;
282 irqstack
= irqstack_end
-
283 (IRQSTACKSIZE
- 64) / sizeof(*irqstack
);
285 if (stack
>= irqstack
&& stack
< irqstack_end
) {
286 if (ops
->stack(data
, "IRQ") < 0)
288 HANDLE_STACK (stack
< irqstack_end
);
290 * We link to the next stack (which would be
291 * the process stack normally) the last
292 * pointer (index -1 to end) in the IRQ stack:
294 stack
= (unsigned long *) (irqstack_end
[-1]);
296 ops
->stack(data
, "EOI");
304 * This handles the process stack:
306 tinfo
= task_thread_info(tsk
);
307 HANDLE_STACK (valid_stack_ptr(tinfo
, stack
));
311 EXPORT_SYMBOL(dump_trace
);
314 print_trace_warning_symbol(void *data
, char *msg
, unsigned long symbol
)
316 print_symbol(msg
, symbol
);
320 static void print_trace_warning(void *data
, char *msg
)
325 static int print_trace_stack(void *data
, char *name
)
327 printk(" <%s> ", name
);
331 static void print_trace_address(void *data
, unsigned long addr
)
333 printk_address(addr
);
336 static struct stacktrace_ops print_trace_ops
= {
337 .warning
= print_trace_warning
,
338 .warning_symbol
= print_trace_warning_symbol
,
339 .stack
= print_trace_stack
,
340 .address
= print_trace_address
,
344 show_trace(struct task_struct
*tsk
, struct pt_regs
*regs
, unsigned long *stack
)
346 printk("\nCall Trace:\n");
347 dump_trace(tsk
, regs
, stack
, &print_trace_ops
, NULL
);
352 _show_stack(struct task_struct
*tsk
, struct pt_regs
*regs
, unsigned long *rsp
)
354 unsigned long *stack
;
356 const int cpu
= smp_processor_id();
357 unsigned long *irqstack_end
= (unsigned long *) (cpu_pda(cpu
)->irqstackptr
);
358 unsigned long *irqstack
= (unsigned long *) (cpu_pda(cpu
)->irqstackptr
- IRQSTACKSIZE
);
360 // debugging aid: "show_stack(NULL, NULL);" prints the
361 // back trace for this cpu.
365 rsp
= (unsigned long *)tsk
->thread
.rsp
;
367 rsp
= (unsigned long *)&rsp
;
371 for(i
=0; i
< kstack_depth_to_print
; i
++) {
372 if (stack
>= irqstack
&& stack
<= irqstack_end
) {
373 if (stack
== irqstack_end
) {
374 stack
= (unsigned long *) (irqstack_end
[-1]);
378 if (((long) stack
& (THREAD_SIZE
-1)) == 0)
381 if (i
&& ((i
% 4) == 0))
383 printk(" %016lx", *stack
++);
384 touch_nmi_watchdog();
386 show_trace(tsk
, regs
, rsp
);
389 void show_stack(struct task_struct
*tsk
, unsigned long * rsp
)
391 _show_stack(tsk
, NULL
, rsp
);
395 * The architecture-independent dump_stack generator
397 void dump_stack(void)
400 show_trace(NULL
, NULL
, &dummy
);
403 EXPORT_SYMBOL(dump_stack
);
405 void show_registers(struct pt_regs
*regs
)
408 int in_kernel
= !user_mode(regs
);
410 const int cpu
= smp_processor_id();
411 struct task_struct
*cur
= cpu_pda(cpu
)->pcurrent
;
414 printk("CPU %d ", cpu
);
416 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
417 cur
->comm
, cur
->pid
, task_thread_info(cur
), cur
);
420 * When in-kernel, we also print out the stack and code at the
421 * time of the fault..
425 _show_stack(NULL
, regs
, (unsigned long*)rsp
);
428 if (regs
->rip
< PAGE_OFFSET
)
431 for (i
=0; i
<20; i
++) {
433 if (__get_user(c
, &((unsigned char*)regs
->rip
)[i
])) {
435 printk(" Bad RIP value.");
444 int is_valid_bugaddr(unsigned long rip
)
448 if (__copy_from_user(&ud2
, (const void __user
*) rip
, sizeof(ud2
)))
451 return ud2
== 0x0b0f;
455 void out_of_line_bug(void)
459 EXPORT_SYMBOL(out_of_line_bug
);
462 static DEFINE_SPINLOCK(die_lock
);
463 static int die_owner
= -1;
464 static unsigned int die_nest_count
;
466 unsigned __kprobes
long oops_begin(void)
473 /* racy, but better than risking deadlock. */
474 local_irq_save(flags
);
475 cpu
= smp_processor_id();
476 if (!spin_trylock(&die_lock
)) {
477 if (cpu
== die_owner
)
478 /* nested oops. should stop eventually */;
480 spin_lock(&die_lock
);
489 void __kprobes
oops_end(unsigned long flags
)
495 /* We still own the lock */
496 local_irq_restore(flags
);
498 /* Nest count reaches zero, release the lock. */
499 spin_unlock_irqrestore(&die_lock
, flags
);
501 panic("Fatal exception");
505 void __kprobes
__die(const char * str
, struct pt_regs
* regs
, long err
)
507 static int die_counter
;
508 printk(KERN_EMERG
"%s: %04lx [%u] ", str
, err
& 0xffff,++die_counter
);
509 #ifdef CONFIG_PREEMPT
515 #ifdef CONFIG_DEBUG_PAGEALLOC
516 printk("DEBUG_PAGEALLOC");
519 notify_die(DIE_OOPS
, str
, regs
, err
, current
->thread
.trap_no
, SIGSEGV
);
520 show_registers(regs
);
521 /* Executive summary in case the oops scrolled away */
522 printk(KERN_ALERT
"RIP ");
523 printk_address(regs
->rip
);
524 printk(" RSP <%016lx>\n", regs
->rsp
);
525 if (kexec_should_crash(current
))
529 void die(const char * str
, struct pt_regs
* regs
, long err
)
531 unsigned long flags
= oops_begin();
533 if (!user_mode(regs
))
534 report_bug(regs
->rip
);
536 __die(str
, regs
, err
);
541 void __kprobes
die_nmi(char *str
, struct pt_regs
*regs
, int do_panic
)
543 unsigned long flags
= oops_begin();
546 * We are in trouble anyway, lets at least try
547 * to get a message out.
549 printk(str
, smp_processor_id());
550 show_registers(regs
);
551 if (kexec_should_crash(current
))
553 if (do_panic
|| panic_on_oops
)
554 panic("Non maskable interrupt");
561 static void __kprobes
do_trap(int trapnr
, int signr
, char *str
,
562 struct pt_regs
* regs
, long error_code
,
565 struct task_struct
*tsk
= current
;
567 if (user_mode(regs
)) {
569 * We want error_code and trap_no set for userspace
570 * faults and kernelspace faults which result in
571 * die(), but not kernelspace faults which are fixed
572 * up. die() gives the process no chance to handle
573 * the signal and notice the kernel fault information,
574 * so that won't result in polluting the information
575 * about previously queued, but not yet delivered,
576 * faults. See also do_general_protection below.
578 tsk
->thread
.error_code
= error_code
;
579 tsk
->thread
.trap_no
= trapnr
;
581 if (exception_trace
&& unhandled_signal(tsk
, signr
))
583 "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
584 tsk
->comm
, tsk
->pid
, str
,
585 regs
->rip
, regs
->rsp
, error_code
);
588 force_sig_info(signr
, info
, tsk
);
590 force_sig(signr
, tsk
);
597 const struct exception_table_entry
*fixup
;
598 fixup
= search_exception_tables(regs
->rip
);
600 regs
->rip
= fixup
->fixup
;
602 tsk
->thread
.error_code
= error_code
;
603 tsk
->thread
.trap_no
= trapnr
;
604 die(str
, regs
, error_code
);
610 #define DO_ERROR(trapnr, signr, str, name) \
611 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
613 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
616 conditional_sti(regs); \
617 do_trap(trapnr, signr, str, regs, error_code, NULL); \
620 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
621 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
624 info.si_signo = signr; \
626 info.si_code = sicode; \
627 info.si_addr = (void __user *)siaddr; \
628 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
631 conditional_sti(regs); \
632 do_trap(trapnr, signr, str, regs, error_code, &info); \
635 DO_ERROR_INFO( 0, SIGFPE
, "divide error", divide_error
, FPE_INTDIV
, regs
->rip
)
636 DO_ERROR( 4, SIGSEGV
, "overflow", overflow
)
637 DO_ERROR( 5, SIGSEGV
, "bounds", bounds
)
638 DO_ERROR_INFO( 6, SIGILL
, "invalid opcode", invalid_op
, ILL_ILLOPN
, regs
->rip
)
639 DO_ERROR( 7, SIGSEGV
, "device not available", device_not_available
)
640 DO_ERROR( 9, SIGFPE
, "coprocessor segment overrun", coprocessor_segment_overrun
)
641 DO_ERROR(10, SIGSEGV
, "invalid TSS", invalid_TSS
)
642 DO_ERROR(11, SIGBUS
, "segment not present", segment_not_present
)
643 DO_ERROR_INFO(17, SIGBUS
, "alignment check", alignment_check
, BUS_ADRALN
, 0)
644 DO_ERROR(18, SIGSEGV
, "reserved", reserved
)
646 /* Runs on IST stack */
647 asmlinkage
void do_stack_segment(struct pt_regs
*regs
, long error_code
)
649 if (notify_die(DIE_TRAP
, "stack segment", regs
, error_code
,
650 12, SIGBUS
) == NOTIFY_STOP
)
652 preempt_conditional_sti(regs
);
653 do_trap(12, SIGBUS
, "stack segment", regs
, error_code
, NULL
);
654 preempt_conditional_cli(regs
);
657 asmlinkage
void do_double_fault(struct pt_regs
* regs
, long error_code
)
659 static const char str
[] = "double fault";
660 struct task_struct
*tsk
= current
;
662 /* Return not checked because double check cannot be ignored */
663 notify_die(DIE_TRAP
, str
, regs
, error_code
, 8, SIGSEGV
);
665 tsk
->thread
.error_code
= error_code
;
666 tsk
->thread
.trap_no
= 8;
668 /* This is always a kernel trap and never fixable (and thus must
671 die(str
, regs
, error_code
);
674 asmlinkage
void __kprobes
do_general_protection(struct pt_regs
* regs
,
677 struct task_struct
*tsk
= current
;
679 conditional_sti(regs
);
681 if (user_mode(regs
)) {
682 tsk
->thread
.error_code
= error_code
;
683 tsk
->thread
.trap_no
= 13;
685 if (exception_trace
&& unhandled_signal(tsk
, SIGSEGV
))
687 "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
689 regs
->rip
, regs
->rsp
, error_code
);
691 force_sig(SIGSEGV
, tsk
);
697 const struct exception_table_entry
*fixup
;
698 fixup
= search_exception_tables(regs
->rip
);
700 regs
->rip
= fixup
->fixup
;
704 tsk
->thread
.error_code
= error_code
;
705 tsk
->thread
.trap_no
= 13;
706 if (notify_die(DIE_GPF
, "general protection fault", regs
,
707 error_code
, 13, SIGSEGV
) == NOTIFY_STOP
)
709 die("general protection fault", regs
, error_code
);
713 static __kprobes
void
714 mem_parity_error(unsigned char reason
, struct pt_regs
* regs
)
716 printk(KERN_EMERG
"Uhhuh. NMI received for unknown reason %02x.\n",
718 printk(KERN_EMERG
"You have some hardware problem, likely on the PCI bus.\n");
720 if (panic_on_unrecovered_nmi
)
721 panic("NMI: Not continuing");
723 printk(KERN_EMERG
"Dazed and confused, but trying to continue\n");
725 /* Clear and disable the memory parity error line. */
726 reason
= (reason
& 0xf) | 4;
730 static __kprobes
void
731 io_check_error(unsigned char reason
, struct pt_regs
* regs
)
733 printk("NMI: IOCK error (debug interrupt?)\n");
734 show_registers(regs
);
736 /* Re-enable the IOCK line, wait for a few seconds */
737 reason
= (reason
& 0xf) | 8;
744 static __kprobes
void
745 unknown_nmi_error(unsigned char reason
, struct pt_regs
* regs
)
747 printk(KERN_EMERG
"Uhhuh. NMI received for unknown reason %02x.\n",
749 printk(KERN_EMERG
"Do you have a strange power saving mode enabled?\n");
751 if (panic_on_unrecovered_nmi
)
752 panic("NMI: Not continuing");
754 printk(KERN_EMERG
"Dazed and confused, but trying to continue\n");
757 /* Runs on IST stack. This code must keep interrupts off all the time.
758 Nested NMIs are prevented by the CPU. */
759 asmlinkage __kprobes
void default_do_nmi(struct pt_regs
*regs
)
761 unsigned char reason
= 0;
764 cpu
= smp_processor_id();
766 /* Only the BSP gets external NMIs from the system. */
768 reason
= get_nmi_reason();
770 if (!(reason
& 0xc0)) {
771 if (notify_die(DIE_NMI_IPI
, "nmi_ipi", regs
, reason
, 2, SIGINT
)
775 * Ok, so this is none of the documented NMI sources,
776 * so it must be the NMI watchdog.
778 if (nmi_watchdog_tick(regs
,reason
))
780 if (!do_nmi_callback(regs
,cpu
))
781 unknown_nmi_error(reason
, regs
);
785 if (notify_die(DIE_NMI
, "nmi", regs
, reason
, 2, SIGINT
) == NOTIFY_STOP
)
788 /* AK: following checks seem to be broken on modern chipsets. FIXME */
791 mem_parity_error(reason
, regs
);
793 io_check_error(reason
, regs
);
796 /* runs on IST stack. */
797 asmlinkage
void __kprobes
do_int3(struct pt_regs
* regs
, long error_code
)
799 if (notify_die(DIE_INT3
, "int3", regs
, error_code
, 3, SIGTRAP
) == NOTIFY_STOP
) {
802 preempt_conditional_sti(regs
);
803 do_trap(3, SIGTRAP
, "int3", regs
, error_code
, NULL
);
804 preempt_conditional_cli(regs
);
807 /* Help handler running on IST stack to switch back to user stack
808 for scheduling or signal handling. The actual stack switch is done in
810 asmlinkage __kprobes
struct pt_regs
*sync_regs(struct pt_regs
*eregs
)
812 struct pt_regs
*regs
= eregs
;
813 /* Did already sync */
814 if (eregs
== (struct pt_regs
*)eregs
->rsp
)
816 /* Exception from user space */
817 else if (user_mode(eregs
))
818 regs
= task_pt_regs(current
);
819 /* Exception from kernel and interrupts are enabled. Move to
820 kernel process stack. */
821 else if (eregs
->eflags
& X86_EFLAGS_IF
)
822 regs
= (struct pt_regs
*)(eregs
->rsp
-= sizeof(struct pt_regs
));
828 /* runs on IST stack. */
829 asmlinkage
void __kprobes
do_debug(struct pt_regs
* regs
,
830 unsigned long error_code
)
832 unsigned long condition
;
833 struct task_struct
*tsk
= current
;
836 get_debugreg(condition
, 6);
838 if (notify_die(DIE_DEBUG
, "debug", regs
, condition
, error_code
,
839 SIGTRAP
) == NOTIFY_STOP
)
842 preempt_conditional_sti(regs
);
844 /* Mask out spurious debug traps due to lazy DR7 setting */
845 if (condition
& (DR_TRAP0
|DR_TRAP1
|DR_TRAP2
|DR_TRAP3
)) {
846 if (!tsk
->thread
.debugreg7
) {
851 tsk
->thread
.debugreg6
= condition
;
853 /* Mask out spurious TF errors due to lazy TF clearing */
854 if (condition
& DR_STEP
) {
856 * The TF error should be masked out only if the current
857 * process is not traced and if the TRAP flag has been set
858 * previously by a tracing process (condition detected by
859 * the PT_DTRACE flag); remember that the i386 TRAP flag
860 * can be modified by the process itself in user mode,
861 * allowing programs to debug themselves without the ptrace()
864 if (!user_mode(regs
))
865 goto clear_TF_reenable
;
867 * Was the TF flag set by a debugger? If so, clear it now,
868 * so that register information is correct.
870 if (tsk
->ptrace
& PT_DTRACE
) {
871 regs
->eflags
&= ~TF_MASK
;
872 tsk
->ptrace
&= ~PT_DTRACE
;
876 /* Ok, finally something we can handle */
877 tsk
->thread
.trap_no
= 1;
878 tsk
->thread
.error_code
= error_code
;
879 info
.si_signo
= SIGTRAP
;
881 info
.si_code
= TRAP_BRKPT
;
882 info
.si_addr
= user_mode(regs
) ? (void __user
*)regs
->rip
: NULL
;
883 force_sig_info(SIGTRAP
, &info
, tsk
);
886 set_debugreg(0UL, 7);
887 preempt_conditional_cli(regs
);
891 set_tsk_thread_flag(tsk
, TIF_SINGLESTEP
);
892 regs
->eflags
&= ~TF_MASK
;
893 preempt_conditional_cli(regs
);
896 static int kernel_math_error(struct pt_regs
*regs
, const char *str
, int trapnr
)
898 const struct exception_table_entry
*fixup
;
899 fixup
= search_exception_tables(regs
->rip
);
901 regs
->rip
= fixup
->fixup
;
904 notify_die(DIE_GPF
, str
, regs
, 0, trapnr
, SIGFPE
);
905 /* Illegal floating point operation in the kernel */
906 current
->thread
.trap_no
= trapnr
;
912 * Note that we play around with the 'TS' bit in an attempt to get
913 * the correct behaviour even in the presence of the asynchronous
916 asmlinkage
void do_coprocessor_error(struct pt_regs
*regs
)
918 void __user
*rip
= (void __user
*)(regs
->rip
);
919 struct task_struct
* task
;
921 unsigned short cwd
, swd
;
923 conditional_sti(regs
);
924 if (!user_mode(regs
) &&
925 kernel_math_error(regs
, "kernel x87 math error", 16))
929 * Save the info for the exception handler and clear the error.
933 task
->thread
.trap_no
= 16;
934 task
->thread
.error_code
= 0;
935 info
.si_signo
= SIGFPE
;
937 info
.si_code
= __SI_FAULT
;
940 * (~cwd & swd) will mask out exceptions that are not set to unmasked
941 * status. 0x3f is the exception bits in these regs, 0x200 is the
942 * C1 reg you need in case of a stack fault, 0x040 is the stack
943 * fault bit. We should only be taking one exception at a time,
944 * so if this combination doesn't produce any single exception,
945 * then we have a bad program that isn't synchronizing its FPU usage
946 * and it will suffer the consequences since we won't be able to
947 * fully reproduce the context of the exception
949 cwd
= get_fpu_cwd(task
);
950 swd
= get_fpu_swd(task
);
951 switch (swd
& ~cwd
& 0x3f) {
955 case 0x001: /* Invalid Op */
957 * swd & 0x240 == 0x040: Stack Underflow
958 * swd & 0x240 == 0x240: Stack Overflow
959 * User must clear the SF bit (0x40) if set
961 info
.si_code
= FPE_FLTINV
;
963 case 0x002: /* Denormalize */
964 case 0x010: /* Underflow */
965 info
.si_code
= FPE_FLTUND
;
967 case 0x004: /* Zero Divide */
968 info
.si_code
= FPE_FLTDIV
;
970 case 0x008: /* Overflow */
971 info
.si_code
= FPE_FLTOVF
;
973 case 0x020: /* Precision */
974 info
.si_code
= FPE_FLTRES
;
977 force_sig_info(SIGFPE
, &info
, task
);
980 asmlinkage
void bad_intr(void)
982 printk("bad interrupt");
985 asmlinkage
void do_simd_coprocessor_error(struct pt_regs
*regs
)
987 void __user
*rip
= (void __user
*)(regs
->rip
);
988 struct task_struct
* task
;
990 unsigned short mxcsr
;
992 conditional_sti(regs
);
993 if (!user_mode(regs
) &&
994 kernel_math_error(regs
, "kernel simd math error", 19))
998 * Save the info for the exception handler and clear the error.
1001 save_init_fpu(task
);
1002 task
->thread
.trap_no
= 19;
1003 task
->thread
.error_code
= 0;
1004 info
.si_signo
= SIGFPE
;
1006 info
.si_code
= __SI_FAULT
;
1009 * The SIMD FPU exceptions are handled a little differently, as there
1010 * is only a single status/control register. Thus, to determine which
1011 * unmasked exception was caught we must mask the exception mask bits
1012 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
1014 mxcsr
= get_fpu_mxcsr(task
);
1015 switch (~((mxcsr
& 0x1f80) >> 7) & (mxcsr
& 0x3f)) {
1019 case 0x001: /* Invalid Op */
1020 info
.si_code
= FPE_FLTINV
;
1022 case 0x002: /* Denormalize */
1023 case 0x010: /* Underflow */
1024 info
.si_code
= FPE_FLTUND
;
1026 case 0x004: /* Zero Divide */
1027 info
.si_code
= FPE_FLTDIV
;
1029 case 0x008: /* Overflow */
1030 info
.si_code
= FPE_FLTOVF
;
1032 case 0x020: /* Precision */
1033 info
.si_code
= FPE_FLTRES
;
1036 force_sig_info(SIGFPE
, &info
, task
);
1039 asmlinkage
void do_spurious_interrupt_bug(struct pt_regs
* regs
)
1043 asmlinkage
void __attribute__((weak
)) smp_thermal_interrupt(void)
1047 asmlinkage
void __attribute__((weak
)) mce_threshold_interrupt(void)
1052 * 'math_state_restore()' saves the current math information in the
1053 * old math state array, and gets the new ones from the current task
1055 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
1056 * Don't touch unless you *really* know how it works.
1058 asmlinkage
void math_state_restore(void)
1060 struct task_struct
*me
= current
;
1061 clts(); /* Allow maths ops (or we recurse) */
1065 restore_fpu_checking(&me
->thread
.i387
.fxsave
);
1066 task_thread_info(me
)->status
|= TS_USEDFPU
;
1070 void __init
trap_init(void)
1072 set_intr_gate(0,÷_error
);
1073 set_intr_gate_ist(1,&debug
,DEBUG_STACK
);
1074 set_intr_gate_ist(2,&nmi
,NMI_STACK
);
1075 set_system_gate_ist(3,&int3
,DEBUG_STACK
); /* int3 can be called from all */
1076 set_system_gate(4,&overflow
); /* int4 can be called from all */
1077 set_intr_gate(5,&bounds
);
1078 set_intr_gate(6,&invalid_op
);
1079 set_intr_gate(7,&device_not_available
);
1080 set_intr_gate_ist(8,&double_fault
, DOUBLEFAULT_STACK
);
1081 set_intr_gate(9,&coprocessor_segment_overrun
);
1082 set_intr_gate(10,&invalid_TSS
);
1083 set_intr_gate(11,&segment_not_present
);
1084 set_intr_gate_ist(12,&stack_segment
,STACKFAULT_STACK
);
1085 set_intr_gate(13,&general_protection
);
1086 set_intr_gate(14,&page_fault
);
1087 set_intr_gate(15,&spurious_interrupt_bug
);
1088 set_intr_gate(16,&coprocessor_error
);
1089 set_intr_gate(17,&alignment_check
);
1090 #ifdef CONFIG_X86_MCE
1091 set_intr_gate_ist(18,&machine_check
, MCE_STACK
);
1093 set_intr_gate(19,&simd_coprocessor_error
);
1095 #ifdef CONFIG_IA32_EMULATION
1096 set_system_gate(IA32_SYSCALL_VECTOR
, ia32_syscall
);
1100 * Should be a barrier for any external CPU state.
1106 static int __init
oops_setup(char *s
)
1110 if (!strcmp(s
, "panic"))
1114 early_param("oops", oops_setup
);
1116 static int __init
kstack_setup(char *s
)
1120 kstack_depth_to_print
= simple_strtoul(s
,NULL
,0);
1123 early_param("kstack", kstack_setup
);