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[PATCH] x86_64: Separate CONFIG_UNWIND_INFO from CONFIG_DEBUG_INFO
[mirror_ubuntu-kernels.git] / arch / x86_64 / kernel / traps.c
CommitLineData
1da177e4
LT		 1/*
2 * linux/arch/x86-64/traps.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
6 *
7 * Pentium III FXSR, SSE support
8 * Gareth Hughes <gareth@valinux.com>, May 2000
9 *
10 * $Id: traps.c,v 1.36 2002/03/24 11:09:10 ak Exp $
11 */
12
13/*
14 * 'Traps.c' handles hardware traps and faults after we have saved some
15 * state in 'entry.S'.
16 */
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>
24#include <linux/mm.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>
35faa714 31#include <linux/nmi.h>
0f2fbdcb 32#include <linux/kprobes.h>
1da177e4
LT		 33
34#include <asm/system.h>
35#include <asm/uaccess.h>
36#include <asm/io.h>
37#include <asm/atomic.h>
38#include <asm/debugreg.h>
39#include <asm/desc.h>
40#include <asm/i387.h>
41#include <asm/kdebug.h>
42#include <asm/processor.h>
43
44#include <asm/smp.h>
45#include <asm/pgalloc.h>
46#include <asm/pda.h>
47#include <asm/proto.h>
48#include <asm/nmi.h>
49
1da177e4
LT		 50extern struct gate_struct idt_table[256];
51
52asmlinkage void divide_error(void);
53asmlinkage void debug(void);
54asmlinkage void nmi(void);
55asmlinkage void int3(void);
56asmlinkage void overflow(void);
57asmlinkage void bounds(void);
58asmlinkage void invalid_op(void);
59asmlinkage void device_not_available(void);
60asmlinkage void double_fault(void);
61asmlinkage void coprocessor_segment_overrun(void);
62asmlinkage void invalid_TSS(void);
63asmlinkage void segment_not_present(void);
64asmlinkage void stack_segment(void);
65asmlinkage void general_protection(void);
66asmlinkage void page_fault(void);
67asmlinkage void coprocessor_error(void);
68asmlinkage void simd_coprocessor_error(void);
69asmlinkage void reserved(void);
70asmlinkage void alignment_check(void);
71asmlinkage void machine_check(void);
72asmlinkage void spurious_interrupt_bug(void);
73asmlinkage void call_debug(void);
74
75struct notifier_block *die_chain;
76static DEFINE_SPINLOCK(die_notifier_lock);
77
78int register_die_notifier(struct notifier_block *nb)
79{
80 int err = 0;
81 unsigned long flags;
82 spin_lock_irqsave(&die_notifier_lock, flags);
83 err = notifier_chain_register(&die_chain, nb);
84 spin_unlock_irqrestore(&die_notifier_lock, flags);
85 return err;
86}
87
88static inline void conditional_sti(struct pt_regs *regs)
89{
90 if (regs->eflags & X86_EFLAGS_IF)
91 local_irq_enable();
92}
93
94static int kstack_depth_to_print = 10;
95
96#ifdef CONFIG_KALLSYMS
97#include <linux/kallsyms.h>
98int printk_address(unsigned long address)
99{
100 unsigned long offset = 0, symsize;
101 const char *symname;
102 char *modname;
103 char *delim = ":";
104 char namebuf[128];
105
106 symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);
107 if (!symname)
108 return printk("[<%016lx>]", address);
109 if (!modname)
110 modname = delim = "";
111 return printk("<%016lx>{%s%s%s%s%+ld}",
112 address,delim,modname,delim,symname,offset);
113}
114#else
115int printk_address(unsigned long address)
116{
117 return printk("[<%016lx>]", address);
118}
119#endif
120
0a658002
AK		 121static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
122 unsigned *usedp, const char **idp)
123{
124 static const char ids[N_EXCEPTION_STACKS][8] = {
125 [DEBUG_STACK - 1] = "#DB",
126 [NMI_STACK - 1] = "NMI",
127 [DOUBLEFAULT_STACK - 1] = "#DF",
128 [STACKFAULT_STACK - 1] = "#SS",
129 [MCE_STACK - 1] = "#MC",
130 };
131 unsigned k;
1da177e4 132
0a658002
AK		 133 for (k = 0; k < N_EXCEPTION_STACKS; k++) {
134 unsigned long end;
135
136 end = per_cpu(init_tss, cpu).ist[k];
137 if (stack >= end)
138 continue;
139 if (stack >= end - EXCEPTION_STKSZ) {
140 if (*usedp & (1U << k))
141 break;
142 *usedp |= 1U << k;
143 *idp = ids[k];
144 return (unsigned long *)end;
145 }
1da177e4
LT		 146 }
147 return NULL;
0a658002 148}
1da177e4
LT		 149
150/*
151 * x86-64 can have upto three kernel stacks:
152 * process stack
153 * interrupt stack
0a658002 154 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
1da177e4
LT		 155 */
156
157void show_trace(unsigned long *stack)
158{
159 unsigned long addr;
0a658002
AK		 160 const unsigned cpu = safe_smp_processor_id();
161 unsigned long *irqstack_end = (unsigned long *)cpu_pda[cpu].irqstackptr;
1da177e4 162 int i;
0a658002 163 unsigned used = 0;
1da177e4
LT		 164
165 printk("\nCall Trace:");
0a658002
AK		 166
167#define HANDLE_STACK(cond) \
168 do while (cond) { \
169 addr = *stack++; \
170 if (kernel_text_address(addr)) { \
171 /* \
172 * If the address is either in the text segment of the \
173 * kernel, or in the region which contains vmalloc'ed \
174 * memory, it *may* be the address of a calling \
175 * routine; if so, print it so that someone tracing \
176 * down the cause of the crash will be able to figure \
177 * out the call path that was taken. \
178 */ \
179 i += printk_address(addr); \
180 if (i > 50) { \
181 printk("\n "); \
182 i = 0; \
183 } \
184 else \
185 i += printk(" "); \
186 } \
187 } while (0)
188
189 for(i = 0; ; ) {
190 const char *id;
191 unsigned long *estack_end;
192 estack_end = in_exception_stack(cpu, (unsigned long)stack,
193 &used, &id);
194
195 if (estack_end) {
196 i += printk(" <%s> ", id);
197 HANDLE_STACK (stack < estack_end);
198 i += printk(" <EOE> ");
199 stack = (unsigned long *) estack_end[-2];
200 continue;
1da177e4 201 }
0a658002
AK		 202 if (irqstack_end) {
203 unsigned long *irqstack;
204 irqstack = irqstack_end -
205 (IRQSTACKSIZE - 64) / sizeof(*irqstack);
206
207 if (stack >= irqstack && stack < irqstack_end) {
208 i += printk(" <IRQ> ");
209 HANDLE_STACK (stack < irqstack_end);
210 stack = (unsigned long *) (irqstack_end[-1]);
211 irqstack_end = NULL;
212 i += printk(" <EOI> ");
213 continue;
1da177e4 214 }
1da177e4 215 }
0a658002 216 break;
1da177e4 217 }
0a658002
AK		 218
219 HANDLE_STACK (((long) stack & (THREAD_SIZE-1)) != 0);
220#undef HANDLE_STACK
1da177e4
LT		 221 printk("\n");
222}
223
224void show_stack(struct task_struct *tsk, unsigned long * rsp)
225{
226 unsigned long *stack;
227 int i;
228 const int cpu = safe_smp_processor_id();
229 unsigned long *irqstack_end = (unsigned long *) (cpu_pda[cpu].irqstackptr);
230 unsigned long *irqstack = (unsigned long *) (cpu_pda[cpu].irqstackptr - IRQSTACKSIZE);
231
232 // debugging aid: "show_stack(NULL, NULL);" prints the
233 // back trace for this cpu.
234
235 if (rsp == NULL) {
236 if (tsk)
237 rsp = (unsigned long *)tsk->thread.rsp;
238 else
239 rsp = (unsigned long *)&rsp;
240 }
241
242 stack = rsp;
243 for(i=0; i < kstack_depth_to_print; i++) {
244 if (stack >= irqstack && stack <= irqstack_end) {
245 if (stack == irqstack_end) {
246 stack = (unsigned long *) (irqstack_end[-1]);
247 printk(" <EOI> ");
248 }
249 } else {
250 if (((long) stack & (THREAD_SIZE-1)) == 0)
251 break;
252 }
253 if (i && ((i % 4) == 0))
254 printk("\n ");
255 printk("%016lx ", *stack++);
35faa714 256 touch_nmi_watchdog();
1da177e4
LT		 257 }
258 show_trace((unsigned long *)rsp);
259}
260
261/*
262 * The architecture-independent dump_stack generator
263 */
264void dump_stack(void)
265{
266 unsigned long dummy;
267 show_trace(&dummy);
268}
269
270EXPORT_SYMBOL(dump_stack);
271
272void show_registers(struct pt_regs *regs)
273{
274 int i;
76381fee 275 int in_kernel = !user_mode(regs);
1da177e4
LT		 276 unsigned long rsp;
277 const int cpu = safe_smp_processor_id();
278 struct task_struct *cur = cpu_pda[cpu].pcurrent;
279
280 rsp = regs->rsp;
281
282 printk("CPU %d ", cpu);
283 __show_regs(regs);
284 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
285 cur->comm, cur->pid, cur->thread_info, cur);
286
287 /*
288 * When in-kernel, we also print out the stack and code at the
289 * time of the fault..
290 */
291 if (in_kernel) {
292
293 printk("Stack: ");
294 show_stack(NULL, (unsigned long*)rsp);
295
296 printk("\nCode: ");
297 if(regs->rip < PAGE_OFFSET)
298 goto bad;
299
300 for(i=0;i<20;i++)
301 {
302 unsigned char c;
303 if(__get_user(c, &((unsigned char*)regs->rip)[i])) {
304bad:
305 printk(" Bad RIP value.");
306 break;
307 }
308 printk("%02x ", c);
309 }
310 }
311 printk("\n");
312}
313
314void handle_BUG(struct pt_regs *regs)
315{
316 struct bug_frame f;
317 char tmp;
318
76381fee 319 if (user_mode(regs))
1da177e4
LT		 320 return;
321 if (__copy_from_user(&f, (struct bug_frame *) regs->rip,
322 sizeof(struct bug_frame)))
323 return;
049cdefe 324 if (f.filename >= 0 ||
1da177e4
LT		 325 f.ud2[0] != 0x0f || f.ud2[1] != 0x0b)
326 return;
049cdefe
JB		 327 if (__get_user(tmp, (char *)(long)f.filename))
328 f.filename = (int)(long)"unmapped filename";
1da177e4 329 printk("----------- [cut here ] --------- [please bite here ] ---------\n");
049cdefe 330 printk(KERN_ALERT "Kernel BUG at %.50s:%d\n", (char *)(long)f.filename, f.line);
1da177e4
LT		 331}
332
4f60fdf6 333#ifdef CONFIG_BUG
1da177e4
LT		 334void out_of_line_bug(void)
335{
336 BUG();
337}
4f60fdf6 338#endif
1da177e4
LT		 339
340static DEFINE_SPINLOCK(die_lock);
341static int die_owner = -1;
342
1209140c 343unsigned long oops_begin(void)
1da177e4 344{
1209140c
JB		 345 int cpu = safe_smp_processor_id();
346 unsigned long flags;
347
348 /* racy, but better than risking deadlock. */
349 local_irq_save(flags);
1da177e4
LT		 350 if (!spin_trylock(&die_lock)) {
351 if (cpu == die_owner)
352 /* nested oops. should stop eventually */;
353 else
1209140c 354 spin_lock(&die_lock);
1da177e4 355 }
1209140c 356 die_owner = cpu;
1da177e4 357 console_verbose();
1209140c
JB		 358 bust_spinlocks(1);
359 return flags;
1da177e4
LT		 360}
361
1209140c 362void oops_end(unsigned long flags)
1da177e4
LT		 363{
364 die_owner = -1;
1209140c
JB		 365 bust_spinlocks(0);
366 spin_unlock_irqrestore(&die_lock, flags);
1da177e4 367 if (panic_on_oops)
1209140c
JB		 368 panic("Oops");
369}
1da177e4
LT		 370
371void __die(const char * str, struct pt_regs * regs, long err)
372{
373 static int die_counter;
374 printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter);
375#ifdef CONFIG_PREEMPT
376 printk("PREEMPT ");
377#endif
378#ifdef CONFIG_SMP
379 printk("SMP ");
380#endif
381#ifdef CONFIG_DEBUG_PAGEALLOC
382 printk("DEBUG_PAGEALLOC");
383#endif
384 printk("\n");
385 notify_die(DIE_OOPS, (char *)str, regs, err, 255, SIGSEGV);
386 show_registers(regs);
387 /* Executive summary in case the oops scrolled away */
388 printk(KERN_ALERT "RIP ");
389 printk_address(regs->rip);
390 printk(" RSP <%016lx>\n", regs->rsp);
391}
392
393void die(const char * str, struct pt_regs * regs, long err)
394{
1209140c
JB		 395 unsigned long flags = oops_begin();
396
1da177e4
LT		 397 handle_BUG(regs);
398 __die(str, regs, err);
1209140c 399 oops_end(flags);
1da177e4
LT		 400 do_exit(SIGSEGV);
401}
402static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
403{
404 if (!(regs->eflags & VM_MASK) && (regs->cs == __KERNEL_CS))
405 die(str, regs, err);
406}
407
408void die_nmi(char *str, struct pt_regs *regs)
409{
1209140c
JB		 410 unsigned long flags = oops_begin();
411
1da177e4
LT		 412 /*
413 * We are in trouble anyway, lets at least try
414 * to get a message out.
415 */
416 printk(str, safe_smp_processor_id());
417 show_registers(regs);
418 if (panic_on_timeout || panic_on_oops)
419 panic("nmi watchdog");
420 printk("console shuts up ...\n");
1209140c 421 oops_end(flags);
1da177e4
LT		 422 do_exit(SIGSEGV);
423}
424
0f2fbdcb
PP		 425static void __kprobes do_trap(int trapnr, int signr, char *str,
426 struct pt_regs * regs, long error_code,
427 siginfo_t *info)
1da177e4
LT		 428{
429 conditional_sti(regs);
430
76381fee 431 if (user_mode(regs)) {
1da177e4
LT		 432 struct task_struct *tsk = current;
433
434 if (exception_trace && unhandled_signal(tsk, signr))
435 printk(KERN_INFO
436 "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
437 tsk->comm, tsk->pid, str,
438 regs->rip,regs->rsp,error_code);
439
440 tsk->thread.error_code = error_code;
441 tsk->thread.trap_no = trapnr;
442 if (info)
443 force_sig_info(signr, info, tsk);
444 else
445 force_sig(signr, tsk);
446 return;
447 }
448
449
450 /* kernel trap */
451 {
452 const struct exception_table_entry *fixup;
453 fixup = search_exception_tables(regs->rip);
454 if (fixup) {
455 regs->rip = fixup->fixup;
456 } else
457 die(str, regs, error_code);
458 return;
459 }
460}
461
462#define DO_ERROR(trapnr, signr, str, name) \
463asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
464{ \
465 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
466 == NOTIFY_STOP) \
467 return; \
468 do_trap(trapnr, signr, str, regs, error_code, NULL); \
469}
470
471#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
472asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
473{ \
474 siginfo_t info; \
475 info.si_signo = signr; \
476 info.si_errno = 0; \
477 info.si_code = sicode; \
478 info.si_addr = (void __user *)siaddr; \
479 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
480 == NOTIFY_STOP) \
481 return; \
482 do_trap(trapnr, signr, str, regs, error_code, &info); \
483}
484
485DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip)
486DO_ERROR( 4, SIGSEGV, "overflow", overflow)
487DO_ERROR( 5, SIGSEGV, "bounds", bounds)
488DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->rip)
489DO_ERROR( 7, SIGSEGV, "device not available", device_not_available)
490DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
491DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
492DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
493DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
494DO_ERROR(18, SIGSEGV, "reserved", reserved)
6fefb0d1
AK		 495DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
496DO_ERROR( 8, SIGSEGV, "double fault", double_fault)
1da177e4 497
0f2fbdcb
PP		 498asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
499 long error_code)
1da177e4
LT		 500{
501 conditional_sti(regs);
502
76381fee 503 if (user_mode(regs)) {
1da177e4
LT		 504 struct task_struct *tsk = current;
505
506 if (exception_trace && unhandled_signal(tsk, SIGSEGV))
507 printk(KERN_INFO
508 "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
509 tsk->comm, tsk->pid,
510 regs->rip,regs->rsp,error_code);
511
512 tsk->thread.error_code = error_code;
513 tsk->thread.trap_no = 13;
514 force_sig(SIGSEGV, tsk);
515 return;
516 }
517
518 /* kernel gp */
519 {
520 const struct exception_table_entry *fixup;
521 fixup = search_exception_tables(regs->rip);
522 if (fixup) {
523 regs->rip = fixup->fixup;
524 return;
525 }
526 if (notify_die(DIE_GPF, "general protection fault", regs,
527 error_code, 13, SIGSEGV) == NOTIFY_STOP)
528 return;
529 die("general protection fault", regs, error_code);
530 }
531}
532
533static void mem_parity_error(unsigned char reason, struct pt_regs * regs)
534{
535 printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n");
536 printk("You probably have a hardware problem with your RAM chips\n");
537
538 /* Clear and disable the memory parity error line. */
539 reason = (reason & 0xf) | 4;
540 outb(reason, 0x61);
541}
542
543static void io_check_error(unsigned char reason, struct pt_regs * regs)
544{
545 printk("NMI: IOCK error (debug interrupt?)\n");
546 show_registers(regs);
547
548 /* Re-enable the IOCK line, wait for a few seconds */
549 reason = (reason & 0xf) | 8;
550 outb(reason, 0x61);
551 mdelay(2000);
552 reason &= ~8;
553 outb(reason, 0x61);
554}
555
556static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
557{ printk("Uhhuh. NMI received for unknown reason %02x.\n", reason);
558 printk("Dazed and confused, but trying to continue\n");
559 printk("Do you have a strange power saving mode enabled?\n");
560}
561
6fefb0d1
AK		 562/* Runs on IST stack. This code must keep interrupts off all the time.
563 Nested NMIs are prevented by the CPU. */
1da177e4
LT		 564asmlinkage void default_do_nmi(struct pt_regs *regs)
565{
566 unsigned char reason = 0;
76e4f660
AR		 567 int cpu;
568
569 cpu = smp_processor_id();
1da177e4
LT		 570
571 /* Only the BSP gets external NMIs from the system. */
76e4f660 572 if (!cpu)
1da177e4
LT		 573 reason = get_nmi_reason();
574
575 if (!(reason & 0xc0)) {
576 if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 0, SIGINT)
577 == NOTIFY_STOP)
578 return;
579#ifdef CONFIG_X86_LOCAL_APIC
580 /*
581 * Ok, so this is none of the documented NMI sources,
582 * so it must be the NMI watchdog.
583 */
584 if (nmi_watchdog > 0) {
585 nmi_watchdog_tick(regs,reason);
586 return;
587 }
588#endif
589 unknown_nmi_error(reason, regs);
590 return;
591 }
592 if (notify_die(DIE_NMI, "nmi", regs, reason, 0, SIGINT) == NOTIFY_STOP)
593 return;
594
595 /* AK: following checks seem to be broken on modern chipsets. FIXME */
596
597 if (reason & 0x80)
598 mem_parity_error(reason, regs);
599 if (reason & 0x40)
600 io_check_error(reason, regs);
601}
602
0f2fbdcb 603asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code)
1da177e4
LT		 604{
605 if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) {
606 return;
607 }
608 do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
609 return;
610}
611
6fefb0d1
AK		 612/* Help handler running on IST stack to switch back to user stack
613 for scheduling or signal handling. The actual stack switch is done in
614 entry.S */
615asmlinkage struct pt_regs *sync_regs(struct pt_regs *eregs)
616{
617 struct pt_regs *regs = eregs;
618 /* Did already sync */
619 if (eregs == (struct pt_regs *)eregs->rsp)
620 ;
621 /* Exception from user space */
76381fee 622 else if (user_mode(eregs))
6fefb0d1
AK		 623 regs = ((struct pt_regs *)current->thread.rsp0) - 1;
624 /* Exception from kernel and interrupts are enabled. Move to
625 kernel process stack. */
626 else if (eregs->eflags & X86_EFLAGS_IF)
627 regs = (struct pt_regs *)(eregs->rsp -= sizeof(struct pt_regs));
628 if (eregs != regs)
629 *regs = *eregs;
630 return regs;
631}
632
1da177e4 633/* runs on IST stack. */
0f2fbdcb
PP		 634asmlinkage void __kprobes do_debug(struct pt_regs * regs,
635 unsigned long error_code)
1da177e4 636{
1da177e4
LT		 637 unsigned long condition;
638 struct task_struct *tsk = current;
639 siginfo_t info;
640
e9129e56 641 get_debugreg(condition, 6);
1da177e4
LT		 642
643 if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
daeeafec 644 SIGTRAP) == NOTIFY_STOP)
6fefb0d1 645 return;
daeeafec 646
1da177e4
LT		 647 conditional_sti(regs);
648
649 /* Mask out spurious debug traps due to lazy DR7 setting */
650 if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) {
651 if (!tsk->thread.debugreg7) {
652 goto clear_dr7;
653 }
654 }
655
656 tsk->thread.debugreg6 = condition;
657
658 /* Mask out spurious TF errors due to lazy TF clearing */
daeeafec 659 if (condition & DR_STEP) {
1da177e4
LT		 660 /*
661 * The TF error should be masked out only if the current
662 * process is not traced and if the TRAP flag has been set
663 * previously by a tracing process (condition detected by
664 * the PT_DTRACE flag); remember that the i386 TRAP flag
665 * can be modified by the process itself in user mode,
666 * allowing programs to debug themselves without the ptrace()
667 * interface.
668 */
76381fee 669 if (!user_mode(regs))
1da177e4 670 goto clear_TF_reenable;
be61bff7
AK		 671 /*
672 * Was the TF flag set by a debugger? If so, clear it now,
673 * so that register information is correct.
674 */
675 if (tsk->ptrace & PT_DTRACE) {
676 regs->eflags &= ~TF_MASK;
677 tsk->ptrace &= ~PT_DTRACE;
678 }
1da177e4
LT		 679 }
680
681 /* Ok, finally something we can handle */
682 tsk->thread.trap_no = 1;
683 tsk->thread.error_code = error_code;
684 info.si_signo = SIGTRAP;
685 info.si_errno = 0;
686 info.si_code = TRAP_BRKPT;
76381fee 687 if (!user_mode(regs))
1da177e4
LT		 688 goto clear_dr7;
689
690 info.si_addr = (void __user *)regs->rip;
691 force_sig_info(SIGTRAP, &info, tsk);
692clear_dr7:
e9129e56 693 set_debugreg(0UL, 7);
6fefb0d1 694 return;
1da177e4
LT		 695
696clear_TF_reenable:
697 set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
1da177e4 698 regs->eflags &= ~TF_MASK;
1da177e4
LT		 699}
700
701static int kernel_math_error(struct pt_regs *regs, char *str)
702{
703 const struct exception_table_entry *fixup;
704 fixup = search_exception_tables(regs->rip);
705 if (fixup) {
706 regs->rip = fixup->fixup;
707 return 1;
708 }
709 notify_die(DIE_GPF, str, regs, 0, 16, SIGFPE);
3a848f63 710 /* Illegal floating point operation in the kernel */
1da177e4 711 die(str, regs, 0);
1da177e4
LT		 712 return 0;
713}
714
715/*
716 * Note that we play around with the 'TS' bit in an attempt to get
717 * the correct behaviour even in the presence of the asynchronous
718 * IRQ13 behaviour
719 */
720asmlinkage void do_coprocessor_error(struct pt_regs *regs)
721{
722 void __user *rip = (void __user *)(regs->rip);
723 struct task_struct * task;
724 siginfo_t info;
725 unsigned short cwd, swd;
726
727 conditional_sti(regs);
76381fee 728 if (!user_mode(regs) &&
1da177e4
LT		 729 kernel_math_error(regs, "kernel x87 math error"))
730 return;
731
732 /*
733 * Save the info for the exception handler and clear the error.
734 */
735 task = current;
736 save_init_fpu(task);
737 task->thread.trap_no = 16;
738 task->thread.error_code = 0;
739 info.si_signo = SIGFPE;
740 info.si_errno = 0;
741 info.si_code = __SI_FAULT;
742 info.si_addr = rip;
743 /*
744 * (~cwd & swd) will mask out exceptions that are not set to unmasked
745 * status. 0x3f is the exception bits in these regs, 0x200 is the
746 * C1 reg you need in case of a stack fault, 0x040 is the stack
747 * fault bit. We should only be taking one exception at a time,
748 * so if this combination doesn't produce any single exception,
749 * then we have a bad program that isn't synchronizing its FPU usage
750 * and it will suffer the consequences since we won't be able to
751 * fully reproduce the context of the exception
752 */
753 cwd = get_fpu_cwd(task);
754 swd = get_fpu_swd(task);
ff347b22 755 switch (swd & ~cwd & 0x3f) {
1da177e4
LT		 756 case 0x000:
757 default:
758 break;
759 case 0x001: /* Invalid Op */
ff347b22
CE		 760 /*
761 * swd & 0x240 == 0x040: Stack Underflow
762 * swd & 0x240 == 0x240: Stack Overflow
763 * User must clear the SF bit (0x40) if set
764 */
1da177e4
LT		 765 info.si_code = FPE_FLTINV;
766 break;
767 case 0x002: /* Denormalize */
768 case 0x010: /* Underflow */
769 info.si_code = FPE_FLTUND;
770 break;
771 case 0x004: /* Zero Divide */
772 info.si_code = FPE_FLTDIV;
773 break;
774 case 0x008: /* Overflow */
775 info.si_code = FPE_FLTOVF;
776 break;
777 case 0x020: /* Precision */
778 info.si_code = FPE_FLTRES;
779 break;
780 }
781 force_sig_info(SIGFPE, &info, task);
782}
783
784asmlinkage void bad_intr(void)
785{
786 printk("bad interrupt");
787}
788
789asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
790{
791 void __user *rip = (void __user *)(regs->rip);
792 struct task_struct * task;
793 siginfo_t info;
794 unsigned short mxcsr;
795
796 conditional_sti(regs);
76381fee 797 if (!user_mode(regs) &&
3a848f63 798 kernel_math_error(regs, "kernel simd math error"))
1da177e4
LT		 799 return;
800
801 /*
802 * Save the info for the exception handler and clear the error.
803 */
804 task = current;
805 save_init_fpu(task);
806 task->thread.trap_no = 19;
807 task->thread.error_code = 0;
808 info.si_signo = SIGFPE;
809 info.si_errno = 0;
810 info.si_code = __SI_FAULT;
811 info.si_addr = rip;
812 /*
813 * The SIMD FPU exceptions are handled a little differently, as there
814 * is only a single status/control register. Thus, to determine which
815 * unmasked exception was caught we must mask the exception mask bits
816 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
817 */
818 mxcsr = get_fpu_mxcsr(task);
819 switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) {
820 case 0x000:
821 default:
822 break;
823 case 0x001: /* Invalid Op */
824 info.si_code = FPE_FLTINV;
825 break;
826 case 0x002: /* Denormalize */
827 case 0x010: /* Underflow */
828 info.si_code = FPE_FLTUND;
829 break;
830 case 0x004: /* Zero Divide */
831 info.si_code = FPE_FLTDIV;
832 break;
833 case 0x008: /* Overflow */
834 info.si_code = FPE_FLTOVF;
835 break;
836 case 0x020: /* Precision */
837 info.si_code = FPE_FLTRES;
838 break;
839 }
840 force_sig_info(SIGFPE, &info, task);
841}
842
843asmlinkage void do_spurious_interrupt_bug(struct pt_regs * regs)
844{
845}
846
847asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
89b831ef
JS		 848{
849}
850
851asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
1da177e4
LT		 852{
853}
854
855/*
856 * 'math_state_restore()' saves the current math information in the
857 * old math state array, and gets the new ones from the current task
858 *
859 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
860 * Don't touch unless you *really* know how it works.
861 */
862asmlinkage void math_state_restore(void)
863{
864 struct task_struct *me = current;
865 clts(); /* Allow maths ops (or we recurse) */
866
867 if (!used_math())
868 init_fpu(me);
869 restore_fpu_checking(&me->thread.i387.fxsave);
870 me->thread_info->status |= TS_USEDFPU;
871}
872
873void do_call_debug(struct pt_regs *regs)
874{
875 notify_die(DIE_CALL, "debug call", regs, 0, 255, SIGINT);
876}
877
878void __init trap_init(void)
879{
880 set_intr_gate(0,&divide_error);
881 set_intr_gate_ist(1,&debug,DEBUG_STACK);
882 set_intr_gate_ist(2,&nmi,NMI_STACK);
883 set_system_gate(3,&int3);
884 set_system_gate(4,&overflow); /* int4-5 can be called from all */
885 set_system_gate(5,&bounds);
886 set_intr_gate(6,&invalid_op);
887 set_intr_gate(7,&device_not_available);
888 set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK);
889 set_intr_gate(9,&coprocessor_segment_overrun);
890 set_intr_gate(10,&invalid_TSS);
891 set_intr_gate(11,&segment_not_present);
892 set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK);
893 set_intr_gate(13,&general_protection);
894 set_intr_gate(14,&page_fault);
895 set_intr_gate(15,&spurious_interrupt_bug);
896 set_intr_gate(16,&coprocessor_error);
897 set_intr_gate(17,&alignment_check);
898#ifdef CONFIG_X86_MCE
899 set_intr_gate_ist(18,&machine_check, MCE_STACK);
900#endif
901 set_intr_gate(19,&simd_coprocessor_error);
902
903#ifdef CONFIG_IA32_EMULATION
904 set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
905#endif
906
907 set_intr_gate(KDB_VECTOR, call_debug);
908
909 /*
910 * Should be a barrier for any external CPU state.
911 */
912 cpu_init();
913}
914
915
916/* Actual parsing is done early in setup.c. */
917static int __init oops_dummy(char *s)
918{
919 panic_on_oops = 1;
920 return -1;
921}
922__setup("oops=", oops_dummy);
923
924static int __init kstack_setup(char *s)
925{
926 kstack_depth_to_print = simple_strtoul(s,NULL,0);
927 return 0;
928}
929__setup("kstack=", kstack_setup);
930
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