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
10 * $Id: traps.c,v 1.36 2002/03/24 11:09:10 ak Exp $
14 * 'Traps.c' handles hardware traps and faults after we have saved some
17 #include <linux/config.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/ptrace.h>
23 #include <linux/timer.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/spinlock.h>
28 #include <linux/interrupt.h>
29 #include <linux/module.h>
30 #include <linux/moduleparam.h>
31 #include <linux/nmi.h>
32 #include <linux/kprobes.h>
34 #include <asm/system.h>
35 #include <asm/uaccess.h>
37 #include <asm/atomic.h>
38 #include <asm/debugreg.h>
41 #include <asm/kdebug.h>
42 #include <asm/processor.h>
45 #include <asm/pgalloc.h>
47 #include <asm/proto.h>
50 extern struct gate_struct idt_table
[256];
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 struct notifier_block
*die_chain
;
75 static DEFINE_SPINLOCK(die_notifier_lock
);
77 int register_die_notifier(struct notifier_block
*nb
)
81 spin_lock_irqsave(&die_notifier_lock
, flags
);
82 err
= notifier_chain_register(&die_chain
, nb
);
83 spin_unlock_irqrestore(&die_notifier_lock
, flags
);
87 static inline void conditional_sti(struct pt_regs
*regs
)
89 if (regs
->eflags
& X86_EFLAGS_IF
)
93 static inline void preempt_conditional_sti(struct pt_regs
*regs
)
96 if (regs
->eflags
& X86_EFLAGS_IF
)
100 static inline void preempt_conditional_cli(struct pt_regs
*regs
)
102 if (regs
->eflags
& X86_EFLAGS_IF
)
104 preempt_enable_no_resched();
107 static int kstack_depth_to_print
= 10;
109 #ifdef CONFIG_KALLSYMS
110 #include <linux/kallsyms.h>
111 int printk_address(unsigned long address
)
113 unsigned long offset
= 0, symsize
;
119 symname
= kallsyms_lookup(address
, &symsize
, &offset
, &modname
, namebuf
);
121 return printk("[<%016lx>]", address
);
123 modname
= delim
= "";
124 return printk("<%016lx>{%s%s%s%s%+ld}",
125 address
,delim
,modname
,delim
,symname
,offset
);
128 int printk_address(unsigned long address
)
130 return printk("[<%016lx>]", address
);
134 static unsigned long *in_exception_stack(unsigned cpu
, unsigned long stack
,
135 unsigned *usedp
, const char **idp
)
137 static char ids
[][8] = {
138 [DEBUG_STACK
- 1] = "#DB",
139 [NMI_STACK
- 1] = "NMI",
140 [DOUBLEFAULT_STACK
- 1] = "#DF",
141 [STACKFAULT_STACK
- 1] = "#SS",
142 [MCE_STACK
- 1] = "#MC",
143 #if DEBUG_STKSZ > EXCEPTION_STKSZ
144 [N_EXCEPTION_STACKS
... N_EXCEPTION_STACKS
+ DEBUG_STKSZ
/ EXCEPTION_STKSZ
- 2] = "#DB[?]"
149 for (k
= 0; k
< N_EXCEPTION_STACKS
; k
++) {
153 #if DEBUG_STKSZ > EXCEPTION_STKSZ
155 end
= cpu_pda(cpu
)->debugstack
+ DEBUG_STKSZ
;
159 end
= per_cpu(init_tss
, cpu
).ist
[k
];
164 if (stack
>= end
- EXCEPTION_STKSZ
) {
165 if (*usedp
& (1U << k
))
169 return (unsigned long *)end
;
171 #if DEBUG_STKSZ > EXCEPTION_STKSZ
172 if (k
== DEBUG_STACK
- 1 && stack
>= end
- DEBUG_STKSZ
) {
173 unsigned j
= N_EXCEPTION_STACKS
- 1;
177 end
-= EXCEPTION_STKSZ
;
178 ids
[j
][4] = '1' + (j
- N_EXCEPTION_STACKS
);
179 } while (stack
< end
- EXCEPTION_STKSZ
);
180 if (*usedp
& (1U << j
))
184 return (unsigned long *)end
;
192 * x86-64 can have upto three kernel stacks:
195 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
198 void show_trace(unsigned long *stack
)
200 const unsigned cpu
= safe_smp_processor_id();
201 unsigned long *irqstack_end
= (unsigned long *)cpu_pda(cpu
)->irqstackptr
;
205 printk("\nCall Trace:");
207 #define HANDLE_STACK(cond) \
209 unsigned long addr = *stack++; \
210 if (kernel_text_address(addr)) { \
218 * If the address is either in the text segment of the \
219 * kernel, or in the region which contains vmalloc'ed \
220 * memory, it *may* be the address of a calling \
221 * routine; if so, print it so that someone tracing \
222 * down the cause of the crash will be able to figure \
223 * out the call path that was taken. \
225 i += printk_address(addr); \
231 unsigned long *estack_end
;
232 estack_end
= in_exception_stack(cpu
, (unsigned long)stack
,
236 i
+= printk(" <%s>", id
);
237 HANDLE_STACK (stack
< estack_end
);
238 i
+= printk(" <EOE>");
239 stack
= (unsigned long *) estack_end
[-2];
243 unsigned long *irqstack
;
244 irqstack
= irqstack_end
-
245 (IRQSTACKSIZE
- 64) / sizeof(*irqstack
);
247 if (stack
>= irqstack
&& stack
< irqstack_end
) {
248 i
+= printk(" <IRQ>");
249 HANDLE_STACK (stack
< irqstack_end
);
250 stack
= (unsigned long *) (irqstack_end
[-1]);
252 i
+= printk(" <EOI>");
259 HANDLE_STACK (((long) stack
& (THREAD_SIZE
-1)) != 0);
264 void show_stack(struct task_struct
*tsk
, unsigned long * rsp
)
266 unsigned long *stack
;
268 const int cpu
= safe_smp_processor_id();
269 unsigned long *irqstack_end
= (unsigned long *) (cpu_pda(cpu
)->irqstackptr
);
270 unsigned long *irqstack
= (unsigned long *) (cpu_pda(cpu
)->irqstackptr
- IRQSTACKSIZE
);
272 // debugging aid: "show_stack(NULL, NULL);" prints the
273 // back trace for this cpu.
277 rsp
= (unsigned long *)tsk
->thread
.rsp
;
279 rsp
= (unsigned long *)&rsp
;
283 for(i
=0; i
< kstack_depth_to_print
; i
++) {
284 if (stack
>= irqstack
&& stack
<= irqstack_end
) {
285 if (stack
== irqstack_end
) {
286 stack
= (unsigned long *) (irqstack_end
[-1]);
290 if (((long) stack
& (THREAD_SIZE
-1)) == 0)
293 if (i
&& ((i
% 4) == 0))
295 printk("%016lx ", *stack
++);
296 touch_nmi_watchdog();
298 show_trace((unsigned long *)rsp
);
302 * The architecture-independent dump_stack generator
304 void dump_stack(void)
310 EXPORT_SYMBOL(dump_stack
);
312 void show_registers(struct pt_regs
*regs
)
315 int in_kernel
= !user_mode(regs
);
317 const int cpu
= safe_smp_processor_id();
318 struct task_struct
*cur
= cpu_pda(cpu
)->pcurrent
;
322 printk("CPU %d ", cpu
);
324 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
325 cur
->comm
, cur
->pid
, task_thread_info(cur
), cur
);
328 * When in-kernel, we also print out the stack and code at the
329 * time of the fault..
334 show_stack(NULL
, (unsigned long*)rsp
);
337 if(regs
->rip
< PAGE_OFFSET
)
343 if(__get_user(c
, &((unsigned char*)regs
->rip
)[i
])) {
345 printk(" Bad RIP value.");
354 void handle_BUG(struct pt_regs
*regs
)
358 const char *prefix
= "";
362 if (__copy_from_user(&f
, (const void __user
*) regs
->rip
,
363 sizeof(struct bug_frame
)))
365 if (f
.filename
>= 0 ||
366 f
.ud2
[0] != 0x0f || f
.ud2
[1] != 0x0b)
368 len
= __strnlen_user((char *)(long)f
.filename
, PATH_MAX
) - 1;
369 if (len
< 0 || len
>= PATH_MAX
)
370 f
.filename
= (int)(long)"unmapped filename";
372 f
.filename
+= len
- 50;
375 printk("----------- [cut here ] --------- [please bite here ] ---------\n");
376 printk(KERN_ALERT
"Kernel BUG at %s%.50s:%d\n", prefix
, (char *)(long)f
.filename
, f
.line
);
380 void out_of_line_bug(void)
386 static DEFINE_SPINLOCK(die_lock
);
387 static int die_owner
= -1;
389 unsigned __kprobes
long oops_begin(void)
391 int cpu
= safe_smp_processor_id();
394 /* racy, but better than risking deadlock. */
395 local_irq_save(flags
);
396 if (!spin_trylock(&die_lock
)) {
397 if (cpu
== die_owner
)
398 /* nested oops. should stop eventually */;
400 spin_lock(&die_lock
);
408 void __kprobes
oops_end(unsigned long flags
)
412 spin_unlock_irqrestore(&die_lock
, flags
);
417 void __kprobes
__die(const char * str
, struct pt_regs
* regs
, long err
)
419 static int die_counter
;
420 printk(KERN_EMERG
"%s: %04lx [%u] ", str
, err
& 0xffff,++die_counter
);
421 #ifdef CONFIG_PREEMPT
427 #ifdef CONFIG_DEBUG_PAGEALLOC
428 printk("DEBUG_PAGEALLOC");
431 notify_die(DIE_OOPS
, str
, regs
, err
, current
->thread
.trap_no
, SIGSEGV
);
432 show_registers(regs
);
433 /* Executive summary in case the oops scrolled away */
434 printk(KERN_ALERT
"RIP ");
435 printk_address(regs
->rip
);
436 printk(" RSP <%016lx>\n", regs
->rsp
);
439 void die(const char * str
, struct pt_regs
* regs
, long err
)
441 unsigned long flags
= oops_begin();
444 __die(str
, regs
, err
);
449 void __kprobes
die_nmi(char *str
, struct pt_regs
*regs
)
451 unsigned long flags
= oops_begin();
454 * We are in trouble anyway, lets at least try
455 * to get a message out.
457 printk(str
, safe_smp_processor_id());
458 show_registers(regs
);
459 if (panic_on_timeout
|| panic_on_oops
)
460 panic("nmi watchdog");
461 printk("console shuts up ...\n");
466 static void __kprobes
do_trap(int trapnr
, int signr
, char *str
,
467 struct pt_regs
* regs
, long error_code
,
470 struct task_struct
*tsk
= current
;
472 conditional_sti(regs
);
474 tsk
->thread
.error_code
= error_code
;
475 tsk
->thread
.trap_no
= trapnr
;
477 if (user_mode(regs
)) {
478 if (exception_trace
&& unhandled_signal(tsk
, signr
))
480 "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
481 tsk
->comm
, tsk
->pid
, str
,
482 regs
->rip
,regs
->rsp
,error_code
);
485 force_sig_info(signr
, info
, tsk
);
487 force_sig(signr
, tsk
);
494 const struct exception_table_entry
*fixup
;
495 fixup
= search_exception_tables(regs
->rip
);
497 regs
->rip
= fixup
->fixup
;
499 die(str
, regs
, error_code
);
504 #define DO_ERROR(trapnr, signr, str, name) \
505 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
507 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
510 do_trap(trapnr, signr, str, regs, error_code, NULL); \
513 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
514 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
517 info.si_signo = signr; \
519 info.si_code = sicode; \
520 info.si_addr = (void __user *)siaddr; \
521 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
524 do_trap(trapnr, signr, str, regs, error_code, &info); \
527 DO_ERROR_INFO( 0, SIGFPE
, "divide error", divide_error
, FPE_INTDIV
, regs
->rip
)
528 DO_ERROR( 4, SIGSEGV
, "overflow", overflow
)
529 DO_ERROR( 5, SIGSEGV
, "bounds", bounds
)
530 DO_ERROR_INFO( 6, SIGILL
, "invalid opcode", invalid_op
, ILL_ILLOPN
, regs
->rip
)
531 DO_ERROR( 7, SIGSEGV
, "device not available", device_not_available
)
532 DO_ERROR( 9, SIGFPE
, "coprocessor segment overrun", coprocessor_segment_overrun
)
533 DO_ERROR(10, SIGSEGV
, "invalid TSS", invalid_TSS
)
534 DO_ERROR(11, SIGBUS
, "segment not present", segment_not_present
)
535 DO_ERROR_INFO(17, SIGBUS
, "alignment check", alignment_check
, BUS_ADRALN
, 0)
536 DO_ERROR(18, SIGSEGV
, "reserved", reserved
)
537 DO_ERROR(12, SIGBUS
, "stack segment", stack_segment
)
539 asmlinkage
void do_double_fault(struct pt_regs
* regs
, long error_code
)
541 static const char str
[] = "double fault";
542 struct task_struct
*tsk
= current
;
544 /* Return not checked because double check cannot be ignored */
545 notify_die(DIE_TRAP
, str
, regs
, error_code
, 8, SIGSEGV
);
547 tsk
->thread
.error_code
= error_code
;
548 tsk
->thread
.trap_no
= 8;
550 /* This is always a kernel trap and never fixable (and thus must
553 die(str
, regs
, error_code
);
556 asmlinkage
void __kprobes
do_general_protection(struct pt_regs
* regs
,
559 struct task_struct
*tsk
= current
;
561 conditional_sti(regs
);
563 tsk
->thread
.error_code
= error_code
;
564 tsk
->thread
.trap_no
= 13;
566 if (user_mode(regs
)) {
567 if (exception_trace
&& unhandled_signal(tsk
, SIGSEGV
))
569 "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
571 regs
->rip
,regs
->rsp
,error_code
);
573 force_sig(SIGSEGV
, tsk
);
579 const struct exception_table_entry
*fixup
;
580 fixup
= search_exception_tables(regs
->rip
);
582 regs
->rip
= fixup
->fixup
;
585 if (notify_die(DIE_GPF
, "general protection fault", regs
,
586 error_code
, 13, SIGSEGV
) == NOTIFY_STOP
)
588 die("general protection fault", regs
, error_code
);
592 static __kprobes
void
593 mem_parity_error(unsigned char reason
, struct pt_regs
* regs
)
595 printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n");
596 printk("You probably have a hardware problem with your RAM chips\n");
598 /* Clear and disable the memory parity error line. */
599 reason
= (reason
& 0xf) | 4;
603 static __kprobes
void
604 io_check_error(unsigned char reason
, struct pt_regs
* regs
)
606 printk("NMI: IOCK error (debug interrupt?)\n");
607 show_registers(regs
);
609 /* Re-enable the IOCK line, wait for a few seconds */
610 reason
= (reason
& 0xf) | 8;
617 static __kprobes
void
618 unknown_nmi_error(unsigned char reason
, struct pt_regs
* regs
)
619 { printk("Uhhuh. NMI received for unknown reason %02x.\n", reason
);
620 printk("Dazed and confused, but trying to continue\n");
621 printk("Do you have a strange power saving mode enabled?\n");
624 /* Runs on IST stack. This code must keep interrupts off all the time.
625 Nested NMIs are prevented by the CPU. */
626 asmlinkage __kprobes
void default_do_nmi(struct pt_regs
*regs
)
628 unsigned char reason
= 0;
631 cpu
= smp_processor_id();
633 /* Only the BSP gets external NMIs from the system. */
635 reason
= get_nmi_reason();
637 if (!(reason
& 0xc0)) {
638 if (notify_die(DIE_NMI_IPI
, "nmi_ipi", regs
, reason
, 2, SIGINT
)
641 #ifdef CONFIG_X86_LOCAL_APIC
643 * Ok, so this is none of the documented NMI sources,
644 * so it must be the NMI watchdog.
646 if (nmi_watchdog
> 0) {
647 nmi_watchdog_tick(regs
,reason
);
651 unknown_nmi_error(reason
, regs
);
654 if (notify_die(DIE_NMI
, "nmi", regs
, reason
, 2, SIGINT
) == NOTIFY_STOP
)
657 /* AK: following checks seem to be broken on modern chipsets. FIXME */
660 mem_parity_error(reason
, regs
);
662 io_check_error(reason
, regs
);
665 /* runs on IST stack. */
666 asmlinkage
void __kprobes
do_int3(struct pt_regs
* regs
, long error_code
)
668 if (notify_die(DIE_INT3
, "int3", regs
, error_code
, 3, SIGTRAP
) == NOTIFY_STOP
) {
671 do_trap(3, SIGTRAP
, "int3", regs
, error_code
, NULL
);
675 /* Help handler running on IST stack to switch back to user stack
676 for scheduling or signal handling. The actual stack switch is done in
678 asmlinkage __kprobes
struct pt_regs
*sync_regs(struct pt_regs
*eregs
)
680 struct pt_regs
*regs
= eregs
;
681 /* Did already sync */
682 if (eregs
== (struct pt_regs
*)eregs
->rsp
)
684 /* Exception from user space */
685 else if (user_mode(eregs
))
686 regs
= task_pt_regs(current
);
687 /* Exception from kernel and interrupts are enabled. Move to
688 kernel process stack. */
689 else if (eregs
->eflags
& X86_EFLAGS_IF
)
690 regs
= (struct pt_regs
*)(eregs
->rsp
-= sizeof(struct pt_regs
));
696 /* runs on IST stack. */
697 asmlinkage
void __kprobes
do_debug(struct pt_regs
* regs
,
698 unsigned long error_code
)
700 unsigned long condition
;
701 struct task_struct
*tsk
= current
;
704 get_debugreg(condition
, 6);
706 if (notify_die(DIE_DEBUG
, "debug", regs
, condition
, error_code
,
707 SIGTRAP
) == NOTIFY_STOP
)
710 preempt_conditional_sti(regs
);
712 /* Mask out spurious debug traps due to lazy DR7 setting */
713 if (condition
& (DR_TRAP0
|DR_TRAP1
|DR_TRAP2
|DR_TRAP3
)) {
714 if (!tsk
->thread
.debugreg7
) {
719 tsk
->thread
.debugreg6
= condition
;
721 /* Mask out spurious TF errors due to lazy TF clearing */
722 if (condition
& DR_STEP
) {
724 * The TF error should be masked out only if the current
725 * process is not traced and if the TRAP flag has been set
726 * previously by a tracing process (condition detected by
727 * the PT_DTRACE flag); remember that the i386 TRAP flag
728 * can be modified by the process itself in user mode,
729 * allowing programs to debug themselves without the ptrace()
732 if (!user_mode(regs
))
733 goto clear_TF_reenable
;
735 * Was the TF flag set by a debugger? If so, clear it now,
736 * so that register information is correct.
738 if (tsk
->ptrace
& PT_DTRACE
) {
739 regs
->eflags
&= ~TF_MASK
;
740 tsk
->ptrace
&= ~PT_DTRACE
;
744 /* Ok, finally something we can handle */
745 tsk
->thread
.trap_no
= 1;
746 tsk
->thread
.error_code
= error_code
;
747 info
.si_signo
= SIGTRAP
;
749 info
.si_code
= TRAP_BRKPT
;
750 info
.si_addr
= user_mode(regs
) ? (void __user
*)regs
->rip
: NULL
;
751 force_sig_info(SIGTRAP
, &info
, tsk
);
754 set_debugreg(0UL, 7);
755 preempt_conditional_cli(regs
);
759 set_tsk_thread_flag(tsk
, TIF_SINGLESTEP
);
760 regs
->eflags
&= ~TF_MASK
;
761 preempt_conditional_cli(regs
);
764 static int kernel_math_error(struct pt_regs
*regs
, const char *str
, int trapnr
)
766 const struct exception_table_entry
*fixup
;
767 fixup
= search_exception_tables(regs
->rip
);
769 regs
->rip
= fixup
->fixup
;
772 notify_die(DIE_GPF
, str
, regs
, 0, trapnr
, SIGFPE
);
773 /* Illegal floating point operation in the kernel */
774 current
->thread
.trap_no
= trapnr
;
780 * Note that we play around with the 'TS' bit in an attempt to get
781 * the correct behaviour even in the presence of the asynchronous
784 asmlinkage
void do_coprocessor_error(struct pt_regs
*regs
)
786 void __user
*rip
= (void __user
*)(regs
->rip
);
787 struct task_struct
* task
;
789 unsigned short cwd
, swd
;
791 conditional_sti(regs
);
792 if (!user_mode(regs
) &&
793 kernel_math_error(regs
, "kernel x87 math error", 16))
797 * Save the info for the exception handler and clear the error.
801 task
->thread
.trap_no
= 16;
802 task
->thread
.error_code
= 0;
803 info
.si_signo
= SIGFPE
;
805 info
.si_code
= __SI_FAULT
;
808 * (~cwd & swd) will mask out exceptions that are not set to unmasked
809 * status. 0x3f is the exception bits in these regs, 0x200 is the
810 * C1 reg you need in case of a stack fault, 0x040 is the stack
811 * fault bit. We should only be taking one exception at a time,
812 * so if this combination doesn't produce any single exception,
813 * then we have a bad program that isn't synchronizing its FPU usage
814 * and it will suffer the consequences since we won't be able to
815 * fully reproduce the context of the exception
817 cwd
= get_fpu_cwd(task
);
818 swd
= get_fpu_swd(task
);
819 switch (swd
& ~cwd
& 0x3f) {
823 case 0x001: /* Invalid Op */
825 * swd & 0x240 == 0x040: Stack Underflow
826 * swd & 0x240 == 0x240: Stack Overflow
827 * User must clear the SF bit (0x40) if set
829 info
.si_code
= FPE_FLTINV
;
831 case 0x002: /* Denormalize */
832 case 0x010: /* Underflow */
833 info
.si_code
= FPE_FLTUND
;
835 case 0x004: /* Zero Divide */
836 info
.si_code
= FPE_FLTDIV
;
838 case 0x008: /* Overflow */
839 info
.si_code
= FPE_FLTOVF
;
841 case 0x020: /* Precision */
842 info
.si_code
= FPE_FLTRES
;
845 force_sig_info(SIGFPE
, &info
, task
);
848 asmlinkage
void bad_intr(void)
850 printk("bad interrupt");
853 asmlinkage
void do_simd_coprocessor_error(struct pt_regs
*regs
)
855 void __user
*rip
= (void __user
*)(regs
->rip
);
856 struct task_struct
* task
;
858 unsigned short mxcsr
;
860 conditional_sti(regs
);
861 if (!user_mode(regs
) &&
862 kernel_math_error(regs
, "kernel simd math error", 19))
866 * Save the info for the exception handler and clear the error.
870 task
->thread
.trap_no
= 19;
871 task
->thread
.error_code
= 0;
872 info
.si_signo
= SIGFPE
;
874 info
.si_code
= __SI_FAULT
;
877 * The SIMD FPU exceptions are handled a little differently, as there
878 * is only a single status/control register. Thus, to determine which
879 * unmasked exception was caught we must mask the exception mask bits
880 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
882 mxcsr
= get_fpu_mxcsr(task
);
883 switch (~((mxcsr
& 0x1f80) >> 7) & (mxcsr
& 0x3f)) {
887 case 0x001: /* Invalid Op */
888 info
.si_code
= FPE_FLTINV
;
890 case 0x002: /* Denormalize */
891 case 0x010: /* Underflow */
892 info
.si_code
= FPE_FLTUND
;
894 case 0x004: /* Zero Divide */
895 info
.si_code
= FPE_FLTDIV
;
897 case 0x008: /* Overflow */
898 info
.si_code
= FPE_FLTOVF
;
900 case 0x020: /* Precision */
901 info
.si_code
= FPE_FLTRES
;
904 force_sig_info(SIGFPE
, &info
, task
);
907 asmlinkage
void do_spurious_interrupt_bug(struct pt_regs
* regs
)
911 asmlinkage
void __attribute__((weak
)) smp_thermal_interrupt(void)
915 asmlinkage
void __attribute__((weak
)) mce_threshold_interrupt(void)
920 * 'math_state_restore()' saves the current math information in the
921 * old math state array, and gets the new ones from the current task
923 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
924 * Don't touch unless you *really* know how it works.
926 asmlinkage
void math_state_restore(void)
928 struct task_struct
*me
= current
;
929 clts(); /* Allow maths ops (or we recurse) */
933 restore_fpu_checking(&me
->thread
.i387
.fxsave
);
934 task_thread_info(me
)->status
|= TS_USEDFPU
;
937 void __init
trap_init(void)
939 set_intr_gate(0,÷_error
);
940 set_intr_gate_ist(1,&debug
,DEBUG_STACK
);
941 set_intr_gate_ist(2,&nmi
,NMI_STACK
);
942 set_system_gate_ist(3,&int3
,DEBUG_STACK
); /* int3 can be called from all */
943 set_system_gate(4,&overflow
); /* int4 can be called from all */
944 set_intr_gate(5,&bounds
);
945 set_intr_gate(6,&invalid_op
);
946 set_intr_gate(7,&device_not_available
);
947 set_intr_gate_ist(8,&double_fault
, DOUBLEFAULT_STACK
);
948 set_intr_gate(9,&coprocessor_segment_overrun
);
949 set_intr_gate(10,&invalid_TSS
);
950 set_intr_gate(11,&segment_not_present
);
951 set_intr_gate_ist(12,&stack_segment
,STACKFAULT_STACK
);
952 set_intr_gate(13,&general_protection
);
953 set_intr_gate(14,&page_fault
);
954 set_intr_gate(15,&spurious_interrupt_bug
);
955 set_intr_gate(16,&coprocessor_error
);
956 set_intr_gate(17,&alignment_check
);
957 #ifdef CONFIG_X86_MCE
958 set_intr_gate_ist(18,&machine_check
, MCE_STACK
);
960 set_intr_gate(19,&simd_coprocessor_error
);
962 #ifdef CONFIG_IA32_EMULATION
963 set_system_gate(IA32_SYSCALL_VECTOR
, ia32_syscall
);
967 * Should be a barrier for any external CPU state.
973 /* Actual parsing is done early in setup.c. */
974 static int __init
oops_dummy(char *s
)
979 __setup("oops=", oops_dummy
);
981 static int __init
kstack_setup(char *s
)
983 kstack_depth_to_print
= simple_strtoul(s
,NULL
,0);
986 __setup("kstack=", kstack_setup
);