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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> | |
31 | ||
32 | #include <asm/system.h> | |
33 | #include <asm/uaccess.h> | |
34 | #include <asm/io.h> | |
35 | #include <asm/atomic.h> | |
36 | #include <asm/debugreg.h> | |
37 | #include <asm/desc.h> | |
38 | #include <asm/i387.h> | |
39 | #include <asm/kdebug.h> | |
40 | #include <asm/processor.h> | |
41 | ||
42 | #include <asm/smp.h> | |
43 | #include <asm/pgalloc.h> | |
44 | #include <asm/pda.h> | |
45 | #include <asm/proto.h> | |
46 | #include <asm/nmi.h> | |
47 | ||
48 | #include <linux/irq.h> | |
49 | ||
50 | ||
51 | extern struct gate_struct idt_table[256]; | |
52 | ||
53 | asmlinkage void divide_error(void); | |
54 | asmlinkage void debug(void); | |
55 | asmlinkage void nmi(void); | |
56 | asmlinkage void int3(void); | |
57 | asmlinkage void overflow(void); | |
58 | asmlinkage void bounds(void); | |
59 | asmlinkage void invalid_op(void); | |
60 | asmlinkage void device_not_available(void); | |
61 | asmlinkage void double_fault(void); | |
62 | asmlinkage void coprocessor_segment_overrun(void); | |
63 | asmlinkage void invalid_TSS(void); | |
64 | asmlinkage void segment_not_present(void); | |
65 | asmlinkage void stack_segment(void); | |
66 | asmlinkage void general_protection(void); | |
67 | asmlinkage void page_fault(void); | |
68 | asmlinkage void coprocessor_error(void); | |
69 | asmlinkage void simd_coprocessor_error(void); | |
70 | asmlinkage void reserved(void); | |
71 | asmlinkage void alignment_check(void); | |
72 | asmlinkage void machine_check(void); | |
73 | asmlinkage void spurious_interrupt_bug(void); | |
74 | asmlinkage void call_debug(void); | |
75 | ||
76 | struct notifier_block *die_chain; | |
77 | static DEFINE_SPINLOCK(die_notifier_lock); | |
78 | ||
79 | int register_die_notifier(struct notifier_block *nb) | |
80 | { | |
81 | int err = 0; | |
82 | unsigned long flags; | |
83 | spin_lock_irqsave(&die_notifier_lock, flags); | |
84 | err = notifier_chain_register(&die_chain, nb); | |
85 | spin_unlock_irqrestore(&die_notifier_lock, flags); | |
86 | return err; | |
87 | } | |
88 | ||
89 | static inline void conditional_sti(struct pt_regs *regs) | |
90 | { | |
91 | if (regs->eflags & X86_EFLAGS_IF) | |
92 | local_irq_enable(); | |
93 | } | |
94 | ||
95 | static int kstack_depth_to_print = 10; | |
96 | ||
97 | #ifdef CONFIG_KALLSYMS | |
98 | #include <linux/kallsyms.h> | |
99 | int printk_address(unsigned long address) | |
100 | { | |
101 | unsigned long offset = 0, symsize; | |
102 | const char *symname; | |
103 | char *modname; | |
104 | char *delim = ":"; | |
105 | char namebuf[128]; | |
106 | ||
107 | symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf); | |
108 | if (!symname) | |
109 | return printk("[<%016lx>]", address); | |
110 | if (!modname) | |
111 | modname = delim = ""; | |
112 | return printk("<%016lx>{%s%s%s%s%+ld}", | |
113 | address,delim,modname,delim,symname,offset); | |
114 | } | |
115 | #else | |
116 | int printk_address(unsigned long address) | |
117 | { | |
118 | return printk("[<%016lx>]", address); | |
119 | } | |
120 | #endif | |
121 | ||
122 | unsigned long *in_exception_stack(int cpu, unsigned long stack) | |
123 | { | |
124 | int k; | |
125 | for (k = 0; k < N_EXCEPTION_STACKS; k++) { | |
126 | struct tss_struct *tss = &per_cpu(init_tss, cpu); | |
127 | unsigned long start = tss->ist[k] - EXCEPTION_STKSZ; | |
128 | ||
129 | if (stack >= start && stack < tss->ist[k]) | |
130 | return (unsigned long *)tss->ist[k]; | |
131 | } | |
132 | return NULL; | |
133 | } | |
134 | ||
135 | /* | |
136 | * x86-64 can have upto three kernel stacks: | |
137 | * process stack | |
138 | * interrupt stack | |
139 | * severe exception (double fault, nmi, stack fault) hardware stack | |
140 | * Check and process them in order. | |
141 | */ | |
142 | ||
143 | void show_trace(unsigned long *stack) | |
144 | { | |
145 | unsigned long addr; | |
146 | unsigned long *irqstack, *irqstack_end, *estack_end; | |
147 | const int cpu = safe_smp_processor_id(); | |
148 | int i; | |
149 | ||
150 | printk("\nCall Trace:"); | |
151 | i = 0; | |
152 | ||
153 | estack_end = in_exception_stack(cpu, (unsigned long)stack); | |
154 | if (estack_end) { | |
155 | while (stack < estack_end) { | |
156 | addr = *stack++; | |
157 | if (__kernel_text_address(addr)) { | |
158 | i += printk_address(addr); | |
159 | i += printk(" "); | |
160 | if (i > 50) { | |
161 | printk("\n"); | |
162 | i = 0; | |
163 | } | |
164 | } | |
165 | } | |
166 | i += printk(" <EOE> "); | |
167 | i += 7; | |
168 | stack = (unsigned long *) estack_end[-2]; | |
169 | } | |
170 | ||
171 | irqstack_end = (unsigned long *) (cpu_pda[cpu].irqstackptr); | |
172 | irqstack = (unsigned long *) (cpu_pda[cpu].irqstackptr - IRQSTACKSIZE + 64); | |
173 | ||
174 | if (stack >= irqstack && stack < irqstack_end) { | |
175 | printk("<IRQ> "); | |
176 | while (stack < irqstack_end) { | |
177 | addr = *stack++; | |
178 | /* | |
179 | * If the address is either in the text segment of the | |
180 | * kernel, or in the region which contains vmalloc'ed | |
181 | * memory, it *may* be the address of a calling | |
182 | * routine; if so, print it so that someone tracing | |
183 | * down the cause of the crash will be able to figure | |
184 | * out the call path that was taken. | |
185 | */ | |
186 | if (__kernel_text_address(addr)) { | |
187 | i += printk_address(addr); | |
188 | i += printk(" "); | |
189 | if (i > 50) { | |
190 | printk("\n "); | |
191 | i = 0; | |
192 | } | |
193 | } | |
194 | } | |
195 | stack = (unsigned long *) (irqstack_end[-1]); | |
196 | printk(" <EOI> "); | |
197 | i += 7; | |
198 | } | |
199 | ||
200 | while (((long) stack & (THREAD_SIZE-1)) != 0) { | |
201 | addr = *stack++; | |
202 | if (__kernel_text_address(addr)) { | |
203 | i += printk_address(addr); | |
204 | i += printk(" "); | |
205 | if (i > 50) { | |
206 | printk("\n "); | |
207 | i = 0; | |
208 | } | |
209 | } | |
210 | } | |
211 | printk("\n"); | |
212 | } | |
213 | ||
214 | void show_stack(struct task_struct *tsk, unsigned long * rsp) | |
215 | { | |
216 | unsigned long *stack; | |
217 | int i; | |
218 | const int cpu = safe_smp_processor_id(); | |
219 | unsigned long *irqstack_end = (unsigned long *) (cpu_pda[cpu].irqstackptr); | |
220 | unsigned long *irqstack = (unsigned long *) (cpu_pda[cpu].irqstackptr - IRQSTACKSIZE); | |
221 | ||
222 | // debugging aid: "show_stack(NULL, NULL);" prints the | |
223 | // back trace for this cpu. | |
224 | ||
225 | if (rsp == NULL) { | |
226 | if (tsk) | |
227 | rsp = (unsigned long *)tsk->thread.rsp; | |
228 | else | |
229 | rsp = (unsigned long *)&rsp; | |
230 | } | |
231 | ||
232 | stack = rsp; | |
233 | for(i=0; i < kstack_depth_to_print; i++) { | |
234 | if (stack >= irqstack && stack <= irqstack_end) { | |
235 | if (stack == irqstack_end) { | |
236 | stack = (unsigned long *) (irqstack_end[-1]); | |
237 | printk(" <EOI> "); | |
238 | } | |
239 | } else { | |
240 | if (((long) stack & (THREAD_SIZE-1)) == 0) | |
241 | break; | |
242 | } | |
243 | if (i && ((i % 4) == 0)) | |
244 | printk("\n "); | |
245 | printk("%016lx ", *stack++); | |
246 | } | |
247 | show_trace((unsigned long *)rsp); | |
248 | } | |
249 | ||
250 | /* | |
251 | * The architecture-independent dump_stack generator | |
252 | */ | |
253 | void dump_stack(void) | |
254 | { | |
255 | unsigned long dummy; | |
256 | show_trace(&dummy); | |
257 | } | |
258 | ||
259 | EXPORT_SYMBOL(dump_stack); | |
260 | ||
261 | void show_registers(struct pt_regs *regs) | |
262 | { | |
263 | int i; | |
264 | int in_kernel = (regs->cs & 3) == 0; | |
265 | unsigned long rsp; | |
266 | const int cpu = safe_smp_processor_id(); | |
267 | struct task_struct *cur = cpu_pda[cpu].pcurrent; | |
268 | ||
269 | rsp = regs->rsp; | |
270 | ||
271 | printk("CPU %d ", cpu); | |
272 | __show_regs(regs); | |
273 | printk("Process %s (pid: %d, threadinfo %p, task %p)\n", | |
274 | cur->comm, cur->pid, cur->thread_info, cur); | |
275 | ||
276 | /* | |
277 | * When in-kernel, we also print out the stack and code at the | |
278 | * time of the fault.. | |
279 | */ | |
280 | if (in_kernel) { | |
281 | ||
282 | printk("Stack: "); | |
283 | show_stack(NULL, (unsigned long*)rsp); | |
284 | ||
285 | printk("\nCode: "); | |
286 | if(regs->rip < PAGE_OFFSET) | |
287 | goto bad; | |
288 | ||
289 | for(i=0;i<20;i++) | |
290 | { | |
291 | unsigned char c; | |
292 | if(__get_user(c, &((unsigned char*)regs->rip)[i])) { | |
293 | bad: | |
294 | printk(" Bad RIP value."); | |
295 | break; | |
296 | } | |
297 | printk("%02x ", c); | |
298 | } | |
299 | } | |
300 | printk("\n"); | |
301 | } | |
302 | ||
303 | void handle_BUG(struct pt_regs *regs) | |
304 | { | |
305 | struct bug_frame f; | |
306 | char tmp; | |
307 | ||
308 | if (regs->cs & 3) | |
309 | return; | |
310 | if (__copy_from_user(&f, (struct bug_frame *) regs->rip, | |
311 | sizeof(struct bug_frame))) | |
312 | return; | |
313 | if ((unsigned long)f.filename < __PAGE_OFFSET || | |
314 | f.ud2[0] != 0x0f || f.ud2[1] != 0x0b) | |
315 | return; | |
316 | if (__get_user(tmp, f.filename)) | |
317 | f.filename = "unmapped filename"; | |
318 | printk("----------- [cut here ] --------- [please bite here ] ---------\n"); | |
319 | printk(KERN_ALERT "Kernel BUG at %.50s:%d\n", f.filename, f.line); | |
320 | } | |
321 | ||
322 | void out_of_line_bug(void) | |
323 | { | |
324 | BUG(); | |
325 | } | |
326 | ||
327 | static DEFINE_SPINLOCK(die_lock); | |
328 | static int die_owner = -1; | |
329 | ||
330 | void oops_begin(void) | |
331 | { | |
332 | int cpu = safe_smp_processor_id(); | |
333 | /* racy, but better than risking deadlock. */ | |
334 | local_irq_disable(); | |
335 | if (!spin_trylock(&die_lock)) { | |
336 | if (cpu == die_owner) | |
337 | /* nested oops. should stop eventually */; | |
338 | else | |
339 | spin_lock(&die_lock); | |
340 | } | |
341 | die_owner = cpu; | |
342 | console_verbose(); | |
343 | bust_spinlocks(1); | |
344 | } | |
345 | ||
346 | void oops_end(void) | |
347 | { | |
348 | die_owner = -1; | |
349 | bust_spinlocks(0); | |
350 | spin_unlock(&die_lock); | |
351 | if (panic_on_oops) | |
352 | panic("Oops"); | |
353 | } | |
354 | ||
355 | void __die(const char * str, struct pt_regs * regs, long err) | |
356 | { | |
357 | static int die_counter; | |
358 | printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter); | |
359 | #ifdef CONFIG_PREEMPT | |
360 | printk("PREEMPT "); | |
361 | #endif | |
362 | #ifdef CONFIG_SMP | |
363 | printk("SMP "); | |
364 | #endif | |
365 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
366 | printk("DEBUG_PAGEALLOC"); | |
367 | #endif | |
368 | printk("\n"); | |
369 | notify_die(DIE_OOPS, (char *)str, regs, err, 255, SIGSEGV); | |
370 | show_registers(regs); | |
371 | /* Executive summary in case the oops scrolled away */ | |
372 | printk(KERN_ALERT "RIP "); | |
373 | printk_address(regs->rip); | |
374 | printk(" RSP <%016lx>\n", regs->rsp); | |
375 | } | |
376 | ||
377 | void die(const char * str, struct pt_regs * regs, long err) | |
378 | { | |
379 | oops_begin(); | |
380 | handle_BUG(regs); | |
381 | __die(str, regs, err); | |
382 | oops_end(); | |
383 | do_exit(SIGSEGV); | |
384 | } | |
385 | static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err) | |
386 | { | |
387 | if (!(regs->eflags & VM_MASK) && (regs->cs == __KERNEL_CS)) | |
388 | die(str, regs, err); | |
389 | } | |
390 | ||
391 | void die_nmi(char *str, struct pt_regs *regs) | |
392 | { | |
393 | oops_begin(); | |
394 | /* | |
395 | * We are in trouble anyway, lets at least try | |
396 | * to get a message out. | |
397 | */ | |
398 | printk(str, safe_smp_processor_id()); | |
399 | show_registers(regs); | |
400 | if (panic_on_timeout || panic_on_oops) | |
401 | panic("nmi watchdog"); | |
402 | printk("console shuts up ...\n"); | |
403 | oops_end(); | |
404 | do_exit(SIGSEGV); | |
405 | } | |
406 | ||
407 | static void do_trap(int trapnr, int signr, char *str, | |
408 | struct pt_regs * regs, long error_code, siginfo_t *info) | |
409 | { | |
410 | conditional_sti(regs); | |
411 | ||
412 | #ifdef CONFIG_CHECKING | |
413 | { | |
414 | unsigned long gs; | |
415 | struct x8664_pda *pda = cpu_pda + safe_smp_processor_id(); | |
416 | rdmsrl(MSR_GS_BASE, gs); | |
417 | if (gs != (unsigned long)pda) { | |
418 | wrmsrl(MSR_GS_BASE, pda); | |
419 | printk("%s: wrong gs %lx expected %p rip %lx\n", str, gs, pda, | |
420 | regs->rip); | |
421 | } | |
422 | } | |
423 | #endif | |
424 | ||
425 | if ((regs->cs & 3) != 0) { | |
426 | struct task_struct *tsk = current; | |
427 | ||
428 | if (exception_trace && unhandled_signal(tsk, signr)) | |
429 | printk(KERN_INFO | |
430 | "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n", | |
431 | tsk->comm, tsk->pid, str, | |
432 | regs->rip,regs->rsp,error_code); | |
433 | ||
434 | tsk->thread.error_code = error_code; | |
435 | tsk->thread.trap_no = trapnr; | |
436 | if (info) | |
437 | force_sig_info(signr, info, tsk); | |
438 | else | |
439 | force_sig(signr, tsk); | |
440 | return; | |
441 | } | |
442 | ||
443 | ||
444 | /* kernel trap */ | |
445 | { | |
446 | const struct exception_table_entry *fixup; | |
447 | fixup = search_exception_tables(regs->rip); | |
448 | if (fixup) { | |
449 | regs->rip = fixup->fixup; | |
450 | } else | |
451 | die(str, regs, error_code); | |
452 | return; | |
453 | } | |
454 | } | |
455 | ||
456 | #define DO_ERROR(trapnr, signr, str, name) \ | |
457 | asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ | |
458 | { \ | |
459 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ | |
460 | == NOTIFY_STOP) \ | |
461 | return; \ | |
462 | do_trap(trapnr, signr, str, regs, error_code, NULL); \ | |
463 | } | |
464 | ||
465 | #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ | |
466 | asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ | |
467 | { \ | |
468 | siginfo_t info; \ | |
469 | info.si_signo = signr; \ | |
470 | info.si_errno = 0; \ | |
471 | info.si_code = sicode; \ | |
472 | info.si_addr = (void __user *)siaddr; \ | |
473 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ | |
474 | == NOTIFY_STOP) \ | |
475 | return; \ | |
476 | do_trap(trapnr, signr, str, regs, error_code, &info); \ | |
477 | } | |
478 | ||
479 | DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip) | |
480 | DO_ERROR( 4, SIGSEGV, "overflow", overflow) | |
481 | DO_ERROR( 5, SIGSEGV, "bounds", bounds) | |
482 | DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->rip) | |
483 | DO_ERROR( 7, SIGSEGV, "device not available", device_not_available) | |
484 | DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun) | |
485 | DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS) | |
486 | DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) | |
487 | DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) | |
488 | DO_ERROR(18, SIGSEGV, "reserved", reserved) | |
489 | ||
490 | #define DO_ERROR_STACK(trapnr, signr, str, name) \ | |
491 | asmlinkage void *do_##name(struct pt_regs * regs, long error_code) \ | |
492 | { \ | |
493 | struct pt_regs *pr = ((struct pt_regs *)(current->thread.rsp0))-1; \ | |
494 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ | |
495 | == NOTIFY_STOP) \ | |
496 | return regs; \ | |
497 | if (regs->cs & 3) { \ | |
498 | memcpy(pr, regs, sizeof(struct pt_regs)); \ | |
499 | regs = pr; \ | |
500 | } \ | |
501 | do_trap(trapnr, signr, str, regs, error_code, NULL); \ | |
502 | return regs; \ | |
503 | } | |
504 | ||
505 | DO_ERROR_STACK(12, SIGBUS, "stack segment", stack_segment) | |
506 | DO_ERROR_STACK( 8, SIGSEGV, "double fault", double_fault) | |
507 | ||
508 | asmlinkage void do_general_protection(struct pt_regs * regs, long error_code) | |
509 | { | |
510 | conditional_sti(regs); | |
511 | ||
512 | #ifdef CONFIG_CHECKING | |
513 | { | |
514 | unsigned long gs; | |
515 | struct x8664_pda *pda = cpu_pda + safe_smp_processor_id(); | |
516 | rdmsrl(MSR_GS_BASE, gs); | |
517 | if (gs != (unsigned long)pda) { | |
518 | wrmsrl(MSR_GS_BASE, pda); | |
519 | oops_in_progress++; | |
520 | printk("general protection handler: wrong gs %lx expected %p\n", gs, pda); | |
521 | oops_in_progress--; | |
522 | } | |
523 | } | |
524 | #endif | |
525 | ||
526 | if ((regs->cs & 3)!=0) { | |
527 | struct task_struct *tsk = current; | |
528 | ||
529 | if (exception_trace && unhandled_signal(tsk, SIGSEGV)) | |
530 | printk(KERN_INFO | |
531 | "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n", | |
532 | tsk->comm, tsk->pid, | |
533 | regs->rip,regs->rsp,error_code); | |
534 | ||
535 | tsk->thread.error_code = error_code; | |
536 | tsk->thread.trap_no = 13; | |
537 | force_sig(SIGSEGV, tsk); | |
538 | return; | |
539 | } | |
540 | ||
541 | /* kernel gp */ | |
542 | { | |
543 | const struct exception_table_entry *fixup; | |
544 | fixup = search_exception_tables(regs->rip); | |
545 | if (fixup) { | |
546 | regs->rip = fixup->fixup; | |
547 | return; | |
548 | } | |
549 | if (notify_die(DIE_GPF, "general protection fault", regs, | |
550 | error_code, 13, SIGSEGV) == NOTIFY_STOP) | |
551 | return; | |
552 | die("general protection fault", regs, error_code); | |
553 | } | |
554 | } | |
555 | ||
556 | static void mem_parity_error(unsigned char reason, struct pt_regs * regs) | |
557 | { | |
558 | printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n"); | |
559 | printk("You probably have a hardware problem with your RAM chips\n"); | |
560 | ||
561 | /* Clear and disable the memory parity error line. */ | |
562 | reason = (reason & 0xf) | 4; | |
563 | outb(reason, 0x61); | |
564 | } | |
565 | ||
566 | static void io_check_error(unsigned char reason, struct pt_regs * regs) | |
567 | { | |
568 | printk("NMI: IOCK error (debug interrupt?)\n"); | |
569 | show_registers(regs); | |
570 | ||
571 | /* Re-enable the IOCK line, wait for a few seconds */ | |
572 | reason = (reason & 0xf) | 8; | |
573 | outb(reason, 0x61); | |
574 | mdelay(2000); | |
575 | reason &= ~8; | |
576 | outb(reason, 0x61); | |
577 | } | |
578 | ||
579 | static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs) | |
580 | { printk("Uhhuh. NMI received for unknown reason %02x.\n", reason); | |
581 | printk("Dazed and confused, but trying to continue\n"); | |
582 | printk("Do you have a strange power saving mode enabled?\n"); | |
583 | } | |
584 | ||
585 | asmlinkage void default_do_nmi(struct pt_regs *regs) | |
586 | { | |
587 | unsigned char reason = 0; | |
588 | ||
589 | /* Only the BSP gets external NMIs from the system. */ | |
590 | if (!smp_processor_id()) | |
591 | reason = get_nmi_reason(); | |
592 | ||
593 | if (!(reason & 0xc0)) { | |
594 | if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 0, SIGINT) | |
595 | == NOTIFY_STOP) | |
596 | return; | |
597 | #ifdef CONFIG_X86_LOCAL_APIC | |
598 | /* | |
599 | * Ok, so this is none of the documented NMI sources, | |
600 | * so it must be the NMI watchdog. | |
601 | */ | |
602 | if (nmi_watchdog > 0) { | |
603 | nmi_watchdog_tick(regs,reason); | |
604 | return; | |
605 | } | |
606 | #endif | |
607 | unknown_nmi_error(reason, regs); | |
608 | return; | |
609 | } | |
610 | if (notify_die(DIE_NMI, "nmi", regs, reason, 0, SIGINT) == NOTIFY_STOP) | |
611 | return; | |
612 | ||
613 | /* AK: following checks seem to be broken on modern chipsets. FIXME */ | |
614 | ||
615 | if (reason & 0x80) | |
616 | mem_parity_error(reason, regs); | |
617 | if (reason & 0x40) | |
618 | io_check_error(reason, regs); | |
619 | } | |
620 | ||
621 | asmlinkage void do_int3(struct pt_regs * regs, long error_code) | |
622 | { | |
623 | if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) { | |
624 | return; | |
625 | } | |
626 | do_trap(3, SIGTRAP, "int3", regs, error_code, NULL); | |
627 | return; | |
628 | } | |
629 | ||
630 | /* runs on IST stack. */ | |
631 | asmlinkage void *do_debug(struct pt_regs * regs, unsigned long error_code) | |
632 | { | |
633 | struct pt_regs *pr; | |
634 | unsigned long condition; | |
635 | struct task_struct *tsk = current; | |
636 | siginfo_t info; | |
637 | ||
638 | pr = (struct pt_regs *)(current->thread.rsp0)-1; | |
639 | if (regs->cs & 3) { | |
640 | memcpy(pr, regs, sizeof(struct pt_regs)); | |
641 | regs = pr; | |
642 | } | |
643 | ||
644 | #ifdef CONFIG_CHECKING | |
645 | { | |
646 | /* RED-PEN interaction with debugger - could destroy gs */ | |
647 | unsigned long gs; | |
648 | struct x8664_pda *pda = cpu_pda + safe_smp_processor_id(); | |
649 | rdmsrl(MSR_GS_BASE, gs); | |
650 | if (gs != (unsigned long)pda) { | |
651 | wrmsrl(MSR_GS_BASE, pda); | |
652 | printk("debug handler: wrong gs %lx expected %p\n", gs, pda); | |
653 | } | |
654 | } | |
655 | #endif | |
656 | ||
657 | asm("movq %%db6,%0" : "=r" (condition)); | |
658 | ||
659 | if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code, | |
660 | SIGTRAP) == NOTIFY_STOP) { | |
661 | return regs; | |
662 | } | |
663 | conditional_sti(regs); | |
664 | ||
665 | /* Mask out spurious debug traps due to lazy DR7 setting */ | |
666 | if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) { | |
667 | if (!tsk->thread.debugreg7) { | |
668 | goto clear_dr7; | |
669 | } | |
670 | } | |
671 | ||
672 | tsk->thread.debugreg6 = condition; | |
673 | ||
674 | /* Mask out spurious TF errors due to lazy TF clearing */ | |
675 | if ((condition & DR_STEP) && | |
676 | (notify_die(DIE_DEBUGSTEP, "debugstep", regs, condition, | |
677 | 1, SIGTRAP) != NOTIFY_STOP)) { | |
678 | /* | |
679 | * The TF error should be masked out only if the current | |
680 | * process is not traced and if the TRAP flag has been set | |
681 | * previously by a tracing process (condition detected by | |
682 | * the PT_DTRACE flag); remember that the i386 TRAP flag | |
683 | * can be modified by the process itself in user mode, | |
684 | * allowing programs to debug themselves without the ptrace() | |
685 | * interface. | |
686 | */ | |
687 | if ((regs->cs & 3) == 0) | |
688 | goto clear_TF_reenable; | |
689 | if ((tsk->ptrace & (PT_DTRACE|PT_PTRACED)) == PT_DTRACE) | |
690 | goto clear_TF; | |
691 | } | |
692 | ||
693 | /* Ok, finally something we can handle */ | |
694 | tsk->thread.trap_no = 1; | |
695 | tsk->thread.error_code = error_code; | |
696 | info.si_signo = SIGTRAP; | |
697 | info.si_errno = 0; | |
698 | info.si_code = TRAP_BRKPT; | |
699 | if ((regs->cs & 3) == 0) | |
700 | goto clear_dr7; | |
701 | ||
702 | info.si_addr = (void __user *)regs->rip; | |
703 | force_sig_info(SIGTRAP, &info, tsk); | |
704 | clear_dr7: | |
705 | asm volatile("movq %0,%%db7"::"r"(0UL)); | |
706 | notify_die(DIE_DEBUG, "debug", regs, condition, 1, SIGTRAP); | |
707 | return regs; | |
708 | ||
709 | clear_TF_reenable: | |
710 | set_tsk_thread_flag(tsk, TIF_SINGLESTEP); | |
711 | ||
712 | clear_TF: | |
713 | /* RED-PEN could cause spurious errors */ | |
714 | if (notify_die(DIE_DEBUG, "debug2", regs, condition, 1, SIGTRAP) | |
715 | != NOTIFY_STOP) | |
716 | regs->eflags &= ~TF_MASK; | |
717 | return regs; | |
718 | } | |
719 | ||
720 | static int kernel_math_error(struct pt_regs *regs, char *str) | |
721 | { | |
722 | const struct exception_table_entry *fixup; | |
723 | fixup = search_exception_tables(regs->rip); | |
724 | if (fixup) { | |
725 | regs->rip = fixup->fixup; | |
726 | return 1; | |
727 | } | |
728 | notify_die(DIE_GPF, str, regs, 0, 16, SIGFPE); | |
729 | #if 0 | |
730 | /* This should be a die, but warn only for now */ | |
731 | die(str, regs, 0); | |
732 | #else | |
733 | printk(KERN_DEBUG "%s: %s at ", current->comm, str); | |
734 | printk_address(regs->rip); | |
735 | printk("\n"); | |
736 | #endif | |
737 | return 0; | |
738 | } | |
739 | ||
740 | /* | |
741 | * Note that we play around with the 'TS' bit in an attempt to get | |
742 | * the correct behaviour even in the presence of the asynchronous | |
743 | * IRQ13 behaviour | |
744 | */ | |
745 | asmlinkage void do_coprocessor_error(struct pt_regs *regs) | |
746 | { | |
747 | void __user *rip = (void __user *)(regs->rip); | |
748 | struct task_struct * task; | |
749 | siginfo_t info; | |
750 | unsigned short cwd, swd; | |
751 | ||
752 | conditional_sti(regs); | |
753 | if ((regs->cs & 3) == 0 && | |
754 | kernel_math_error(regs, "kernel x87 math error")) | |
755 | return; | |
756 | ||
757 | /* | |
758 | * Save the info for the exception handler and clear the error. | |
759 | */ | |
760 | task = current; | |
761 | save_init_fpu(task); | |
762 | task->thread.trap_no = 16; | |
763 | task->thread.error_code = 0; | |
764 | info.si_signo = SIGFPE; | |
765 | info.si_errno = 0; | |
766 | info.si_code = __SI_FAULT; | |
767 | info.si_addr = rip; | |
768 | /* | |
769 | * (~cwd & swd) will mask out exceptions that are not set to unmasked | |
770 | * status. 0x3f is the exception bits in these regs, 0x200 is the | |
771 | * C1 reg you need in case of a stack fault, 0x040 is the stack | |
772 | * fault bit. We should only be taking one exception at a time, | |
773 | * so if this combination doesn't produce any single exception, | |
774 | * then we have a bad program that isn't synchronizing its FPU usage | |
775 | * and it will suffer the consequences since we won't be able to | |
776 | * fully reproduce the context of the exception | |
777 | */ | |
778 | cwd = get_fpu_cwd(task); | |
779 | swd = get_fpu_swd(task); | |
780 | switch (((~cwd) & swd & 0x3f) | (swd & 0x240)) { | |
781 | case 0x000: | |
782 | default: | |
783 | break; | |
784 | case 0x001: /* Invalid Op */ | |
785 | case 0x041: /* Stack Fault */ | |
786 | case 0x241: /* Stack Fault | Direction */ | |
787 | info.si_code = FPE_FLTINV; | |
788 | break; | |
789 | case 0x002: /* Denormalize */ | |
790 | case 0x010: /* Underflow */ | |
791 | info.si_code = FPE_FLTUND; | |
792 | break; | |
793 | case 0x004: /* Zero Divide */ | |
794 | info.si_code = FPE_FLTDIV; | |
795 | break; | |
796 | case 0x008: /* Overflow */ | |
797 | info.si_code = FPE_FLTOVF; | |
798 | break; | |
799 | case 0x020: /* Precision */ | |
800 | info.si_code = FPE_FLTRES; | |
801 | break; | |
802 | } | |
803 | force_sig_info(SIGFPE, &info, task); | |
804 | } | |
805 | ||
806 | asmlinkage void bad_intr(void) | |
807 | { | |
808 | printk("bad interrupt"); | |
809 | } | |
810 | ||
811 | asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs) | |
812 | { | |
813 | void __user *rip = (void __user *)(regs->rip); | |
814 | struct task_struct * task; | |
815 | siginfo_t info; | |
816 | unsigned short mxcsr; | |
817 | ||
818 | conditional_sti(regs); | |
819 | if ((regs->cs & 3) == 0 && | |
820 | kernel_math_error(regs, "simd math error")) | |
821 | return; | |
822 | ||
823 | /* | |
824 | * Save the info for the exception handler and clear the error. | |
825 | */ | |
826 | task = current; | |
827 | save_init_fpu(task); | |
828 | task->thread.trap_no = 19; | |
829 | task->thread.error_code = 0; | |
830 | info.si_signo = SIGFPE; | |
831 | info.si_errno = 0; | |
832 | info.si_code = __SI_FAULT; | |
833 | info.si_addr = rip; | |
834 | /* | |
835 | * The SIMD FPU exceptions are handled a little differently, as there | |
836 | * is only a single status/control register. Thus, to determine which | |
837 | * unmasked exception was caught we must mask the exception mask bits | |
838 | * at 0x1f80, and then use these to mask the exception bits at 0x3f. | |
839 | */ | |
840 | mxcsr = get_fpu_mxcsr(task); | |
841 | switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) { | |
842 | case 0x000: | |
843 | default: | |
844 | break; | |
845 | case 0x001: /* Invalid Op */ | |
846 | info.si_code = FPE_FLTINV; | |
847 | break; | |
848 | case 0x002: /* Denormalize */ | |
849 | case 0x010: /* Underflow */ | |
850 | info.si_code = FPE_FLTUND; | |
851 | break; | |
852 | case 0x004: /* Zero Divide */ | |
853 | info.si_code = FPE_FLTDIV; | |
854 | break; | |
855 | case 0x008: /* Overflow */ | |
856 | info.si_code = FPE_FLTOVF; | |
857 | break; | |
858 | case 0x020: /* Precision */ | |
859 | info.si_code = FPE_FLTRES; | |
860 | break; | |
861 | } | |
862 | force_sig_info(SIGFPE, &info, task); | |
863 | } | |
864 | ||
865 | asmlinkage void do_spurious_interrupt_bug(struct pt_regs * regs) | |
866 | { | |
867 | } | |
868 | ||
869 | asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void) | |
870 | { | |
871 | } | |
872 | ||
873 | /* | |
874 | * 'math_state_restore()' saves the current math information in the | |
875 | * old math state array, and gets the new ones from the current task | |
876 | * | |
877 | * Careful.. There are problems with IBM-designed IRQ13 behaviour. | |
878 | * Don't touch unless you *really* know how it works. | |
879 | */ | |
880 | asmlinkage void math_state_restore(void) | |
881 | { | |
882 | struct task_struct *me = current; | |
883 | clts(); /* Allow maths ops (or we recurse) */ | |
884 | ||
885 | if (!used_math()) | |
886 | init_fpu(me); | |
887 | restore_fpu_checking(&me->thread.i387.fxsave); | |
888 | me->thread_info->status |= TS_USEDFPU; | |
889 | } | |
890 | ||
891 | void do_call_debug(struct pt_regs *regs) | |
892 | { | |
893 | notify_die(DIE_CALL, "debug call", regs, 0, 255, SIGINT); | |
894 | } | |
895 | ||
896 | void __init trap_init(void) | |
897 | { | |
898 | set_intr_gate(0,÷_error); | |
899 | set_intr_gate_ist(1,&debug,DEBUG_STACK); | |
900 | set_intr_gate_ist(2,&nmi,NMI_STACK); | |
901 | set_system_gate(3,&int3); | |
902 | set_system_gate(4,&overflow); /* int4-5 can be called from all */ | |
903 | set_system_gate(5,&bounds); | |
904 | set_intr_gate(6,&invalid_op); | |
905 | set_intr_gate(7,&device_not_available); | |
906 | set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK); | |
907 | set_intr_gate(9,&coprocessor_segment_overrun); | |
908 | set_intr_gate(10,&invalid_TSS); | |
909 | set_intr_gate(11,&segment_not_present); | |
910 | set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK); | |
911 | set_intr_gate(13,&general_protection); | |
912 | set_intr_gate(14,&page_fault); | |
913 | set_intr_gate(15,&spurious_interrupt_bug); | |
914 | set_intr_gate(16,&coprocessor_error); | |
915 | set_intr_gate(17,&alignment_check); | |
916 | #ifdef CONFIG_X86_MCE | |
917 | set_intr_gate_ist(18,&machine_check, MCE_STACK); | |
918 | #endif | |
919 | set_intr_gate(19,&simd_coprocessor_error); | |
920 | ||
921 | #ifdef CONFIG_IA32_EMULATION | |
922 | set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall); | |
923 | #endif | |
924 | ||
925 | set_intr_gate(KDB_VECTOR, call_debug); | |
926 | ||
927 | /* | |
928 | * Should be a barrier for any external CPU state. | |
929 | */ | |
930 | cpu_init(); | |
931 | } | |
932 | ||
933 | ||
934 | /* Actual parsing is done early in setup.c. */ | |
935 | static int __init oops_dummy(char *s) | |
936 | { | |
937 | panic_on_oops = 1; | |
938 | return -1; | |
939 | } | |
940 | __setup("oops=", oops_dummy); | |
941 | ||
942 | static int __init kstack_setup(char *s) | |
943 | { | |
944 | kstack_depth_to_print = simple_strtoul(s,NULL,0); | |
945 | return 0; | |
946 | } | |
947 | __setup("kstack=", kstack_setup); | |
948 |