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Commit | Line | Data |
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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 | |
1da177e4 LT |
9 | */ |
10 | ||
11 | /* | |
12 | * 'Traps.c' handles hardware traps and faults after we have saved some | |
13 | * state in 'entry.S'. | |
14 | */ | |
1da177e4 LT |
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> | |
21 | #include <linux/mm.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/delay.h> | |
24 | #include <linux/spinlock.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/moduleparam.h> | |
35faa714 | 28 | #include <linux/nmi.h> |
0f2fbdcb | 29 | #include <linux/kprobes.h> |
8bcc5280 | 30 | #include <linux/kexec.h> |
b538ed27 | 31 | #include <linux/unwind.h> |
1da177e4 LT |
32 | |
33 | #include <asm/system.h> | |
34 | #include <asm/uaccess.h> | |
35 | #include <asm/io.h> | |
36 | #include <asm/atomic.h> | |
37 | #include <asm/debugreg.h> | |
38 | #include <asm/desc.h> | |
39 | #include <asm/i387.h> | |
40 | #include <asm/kdebug.h> | |
41 | #include <asm/processor.h> | |
b538ed27 | 42 | #include <asm/unwind.h> |
1da177e4 LT |
43 | #include <asm/smp.h> |
44 | #include <asm/pgalloc.h> | |
45 | #include <asm/pda.h> | |
46 | #include <asm/proto.h> | |
47 | #include <asm/nmi.h> | |
c0b766f1 | 48 | #include <asm/stacktrace.h> |
1da177e4 | 49 | |
1da177e4 LT |
50 | asmlinkage void divide_error(void); |
51 | asmlinkage void debug(void); | |
52 | asmlinkage void nmi(void); | |
53 | asmlinkage void int3(void); | |
54 | asmlinkage void overflow(void); | |
55 | asmlinkage void bounds(void); | |
56 | asmlinkage void invalid_op(void); | |
57 | asmlinkage void device_not_available(void); | |
58 | asmlinkage void double_fault(void); | |
59 | asmlinkage void coprocessor_segment_overrun(void); | |
60 | asmlinkage void invalid_TSS(void); | |
61 | asmlinkage void segment_not_present(void); | |
62 | asmlinkage void stack_segment(void); | |
63 | asmlinkage void general_protection(void); | |
64 | asmlinkage void page_fault(void); | |
65 | asmlinkage void coprocessor_error(void); | |
66 | asmlinkage void simd_coprocessor_error(void); | |
67 | asmlinkage void reserved(void); | |
68 | asmlinkage void alignment_check(void); | |
69 | asmlinkage void machine_check(void); | |
70 | asmlinkage void spurious_interrupt_bug(void); | |
1da177e4 | 71 | |
e041c683 | 72 | ATOMIC_NOTIFIER_HEAD(die_chain); |
2ee60e17 | 73 | EXPORT_SYMBOL(die_chain); |
1da177e4 LT |
74 | |
75 | int register_die_notifier(struct notifier_block *nb) | |
76 | { | |
8c914cb7 | 77 | vmalloc_sync_all(); |
e041c683 AS |
78 | return atomic_notifier_chain_register(&die_chain, nb); |
79 | } | |
1454aed9 | 80 | EXPORT_SYMBOL(register_die_notifier); /* used modular by kdb */ |
e041c683 AS |
81 | |
82 | int unregister_die_notifier(struct notifier_block *nb) | |
83 | { | |
84 | return atomic_notifier_chain_unregister(&die_chain, nb); | |
1da177e4 | 85 | } |
1454aed9 | 86 | EXPORT_SYMBOL(unregister_die_notifier); /* used modular by kdb */ |
1da177e4 LT |
87 | |
88 | static inline void conditional_sti(struct pt_regs *regs) | |
89 | { | |
90 | if (regs->eflags & X86_EFLAGS_IF) | |
91 | local_irq_enable(); | |
92 | } | |
93 | ||
a65d17c9 JB |
94 | static inline void preempt_conditional_sti(struct pt_regs *regs) |
95 | { | |
96 | preempt_disable(); | |
97 | if (regs->eflags & X86_EFLAGS_IF) | |
98 | local_irq_enable(); | |
99 | } | |
100 | ||
101 | static inline void preempt_conditional_cli(struct pt_regs *regs) | |
102 | { | |
103 | if (regs->eflags & X86_EFLAGS_IF) | |
104 | local_irq_disable(); | |
40e59a61 AK |
105 | /* Make sure to not schedule here because we could be running |
106 | on an exception stack. */ | |
a65d17c9 JB |
107 | preempt_enable_no_resched(); |
108 | } | |
109 | ||
cab093b9 | 110 | static int kstack_depth_to_print = 12; |
ea424055 | 111 | #ifdef CONFIG_STACK_UNWIND |
c33bd9aa | 112 | static int call_trace = 1; |
ea424055 JB |
113 | #else |
114 | #define call_trace (-1) | |
115 | #endif | |
1da177e4 LT |
116 | |
117 | #ifdef CONFIG_KALLSYMS | |
3ac94932 IM |
118 | # include <linux/kallsyms.h> |
119 | void printk_address(unsigned long address) | |
120 | { | |
1da177e4 LT |
121 | unsigned long offset = 0, symsize; |
122 | const char *symname; | |
123 | char *modname; | |
3ac94932 | 124 | char *delim = ":"; |
1da177e4 LT |
125 | char namebuf[128]; |
126 | ||
3ac94932 IM |
127 | symname = kallsyms_lookup(address, &symsize, &offset, |
128 | &modname, namebuf); | |
129 | if (!symname) { | |
130 | printk(" [<%016lx>]\n", address); | |
131 | return; | |
132 | } | |
133 | if (!modname) | |
1da177e4 | 134 | modname = delim = ""; |
3ac94932 IM |
135 | printk(" [<%016lx>] %s%s%s%s+0x%lx/0x%lx\n", |
136 | address, delim, modname, delim, symname, offset, symsize); | |
137 | } | |
1da177e4 | 138 | #else |
3ac94932 IM |
139 | void printk_address(unsigned long address) |
140 | { | |
141 | printk(" [<%016lx>]\n", address); | |
142 | } | |
1da177e4 LT |
143 | #endif |
144 | ||
0a658002 | 145 | static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, |
c0b766f1 | 146 | unsigned *usedp, char **idp) |
0a658002 | 147 | { |
b556b35e | 148 | static char ids[][8] = { |
0a658002 AK |
149 | [DEBUG_STACK - 1] = "#DB", |
150 | [NMI_STACK - 1] = "NMI", | |
151 | [DOUBLEFAULT_STACK - 1] = "#DF", | |
152 | [STACKFAULT_STACK - 1] = "#SS", | |
153 | [MCE_STACK - 1] = "#MC", | |
b556b35e JB |
154 | #if DEBUG_STKSZ > EXCEPTION_STKSZ |
155 | [N_EXCEPTION_STACKS ... N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]" | |
156 | #endif | |
0a658002 AK |
157 | }; |
158 | unsigned k; | |
1da177e4 | 159 | |
c9ca1ba5 IM |
160 | /* |
161 | * Iterate over all exception stacks, and figure out whether | |
162 | * 'stack' is in one of them: | |
163 | */ | |
0a658002 AK |
164 | for (k = 0; k < N_EXCEPTION_STACKS; k++) { |
165 | unsigned long end; | |
166 | ||
c9ca1ba5 IM |
167 | /* |
168 | * set 'end' to the end of the exception stack. | |
169 | */ | |
b556b35e | 170 | switch (k + 1) { |
c9ca1ba5 IM |
171 | /* |
172 | * TODO: this block is not needed i think, because | |
173 | * setup64.c:cpu_init() sets up t->ist[DEBUG_STACK] | |
174 | * properly too. | |
175 | */ | |
b556b35e JB |
176 | #if DEBUG_STKSZ > EXCEPTION_STKSZ |
177 | case DEBUG_STACK: | |
df79efde | 178 | end = cpu_pda(cpu)->debugstack + DEBUG_STKSZ; |
b556b35e JB |
179 | break; |
180 | #endif | |
181 | default: | |
01ebb77b | 182 | end = per_cpu(orig_ist, cpu).ist[k]; |
b556b35e JB |
183 | break; |
184 | } | |
c9ca1ba5 IM |
185 | /* |
186 | * Is 'stack' above this exception frame's end? | |
187 | * If yes then skip to the next frame. | |
188 | */ | |
0a658002 AK |
189 | if (stack >= end) |
190 | continue; | |
c9ca1ba5 IM |
191 | /* |
192 | * Is 'stack' above this exception frame's start address? | |
193 | * If yes then we found the right frame. | |
194 | */ | |
0a658002 | 195 | if (stack >= end - EXCEPTION_STKSZ) { |
c9ca1ba5 IM |
196 | /* |
197 | * Make sure we only iterate through an exception | |
198 | * stack once. If it comes up for the second time | |
199 | * then there's something wrong going on - just | |
200 | * break out and return NULL: | |
201 | */ | |
0a658002 AK |
202 | if (*usedp & (1U << k)) |
203 | break; | |
204 | *usedp |= 1U << k; | |
205 | *idp = ids[k]; | |
206 | return (unsigned long *)end; | |
207 | } | |
c9ca1ba5 IM |
208 | /* |
209 | * If this is a debug stack, and if it has a larger size than | |
210 | * the usual exception stacks, then 'stack' might still | |
211 | * be within the lower portion of the debug stack: | |
212 | */ | |
b556b35e JB |
213 | #if DEBUG_STKSZ > EXCEPTION_STKSZ |
214 | if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) { | |
215 | unsigned j = N_EXCEPTION_STACKS - 1; | |
216 | ||
c9ca1ba5 IM |
217 | /* |
218 | * Black magic. A large debug stack is composed of | |
219 | * multiple exception stack entries, which we | |
220 | * iterate through now. Dont look: | |
221 | */ | |
b556b35e JB |
222 | do { |
223 | ++j; | |
224 | end -= EXCEPTION_STKSZ; | |
225 | ids[j][4] = '1' + (j - N_EXCEPTION_STACKS); | |
226 | } while (stack < end - EXCEPTION_STKSZ); | |
227 | if (*usedp & (1U << j)) | |
228 | break; | |
229 | *usedp |= 1U << j; | |
230 | *idp = ids[j]; | |
231 | return (unsigned long *)end; | |
232 | } | |
233 | #endif | |
1da177e4 LT |
234 | } |
235 | return NULL; | |
0a658002 | 236 | } |
1da177e4 | 237 | |
c0b766f1 AK |
238 | struct ops_and_data { |
239 | struct stacktrace_ops *ops; | |
240 | void *data; | |
241 | }; | |
242 | ||
243 | static int dump_trace_unwind(struct unwind_frame_info *info, void *context) | |
b538ed27 | 244 | { |
c0b766f1 | 245 | struct ops_and_data *oad = (struct ops_and_data *)context; |
3ac94932 | 246 | int n = 0; |
b538ed27 JB |
247 | |
248 | while (unwind(info) == 0 && UNW_PC(info)) { | |
3ac94932 | 249 | n++; |
c0b766f1 | 250 | oad->ops->address(oad->data, UNW_PC(info)); |
b538ed27 JB |
251 | if (arch_unw_user_mode(info)) |
252 | break; | |
253 | } | |
c33bd9aa | 254 | return n; |
b538ed27 JB |
255 | } |
256 | ||
1da177e4 LT |
257 | /* |
258 | * x86-64 can have upto three kernel stacks: | |
259 | * process stack | |
260 | * interrupt stack | |
0a658002 | 261 | * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack |
1da177e4 LT |
262 | */ |
263 | ||
c0b766f1 AK |
264 | void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * stack, |
265 | struct stacktrace_ops *ops, void *data) | |
1da177e4 | 266 | { |
0a658002 | 267 | const unsigned cpu = safe_smp_processor_id(); |
df79efde | 268 | unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr; |
0a658002 | 269 | unsigned used = 0; |
1da177e4 | 270 | |
b538ed27 JB |
271 | if (!tsk) |
272 | tsk = current; | |
273 | ||
c33bd9aa JB |
274 | if (call_trace >= 0) { |
275 | int unw_ret = 0; | |
276 | struct unwind_frame_info info; | |
c0b766f1 | 277 | struct ops_and_data oad = { .ops = ops, .data = data }; |
c33bd9aa JB |
278 | |
279 | if (regs) { | |
280 | if (unwind_init_frame_info(&info, tsk, regs) == 0) | |
c0b766f1 | 281 | unw_ret = dump_trace_unwind(&info, &oad); |
c33bd9aa | 282 | } else if (tsk == current) |
c0b766f1 | 283 | unw_ret = unwind_init_running(&info, dump_trace_unwind, &oad); |
c33bd9aa JB |
284 | else { |
285 | if (unwind_init_blocked(&info, tsk) == 0) | |
c0b766f1 | 286 | unw_ret = dump_trace_unwind(&info, &oad); |
b538ed27 | 287 | } |
ea424055 JB |
288 | if (unw_ret > 0) { |
289 | if (call_trace == 1 && !arch_unw_user_mode(&info)) { | |
c0b766f1 | 290 | ops->warning_symbol(data, "DWARF2 unwinder stuck at %s\n", |
ea424055 JB |
291 | UNW_PC(&info)); |
292 | if ((long)UNW_SP(&info) < 0) { | |
c0b766f1 | 293 | ops->warning(data, "Leftover inexact backtrace:\n"); |
ea424055 | 294 | stack = (unsigned long *)UNW_SP(&info); |
be7a9170 AK |
295 | if (!stack) |
296 | return; | |
ea424055 | 297 | } else |
c0b766f1 | 298 | ops->warning(data, "Full inexact backtrace again:\n"); |
ea424055 | 299 | } else if (call_trace >= 1) |
c33bd9aa | 300 | return; |
b13761ec | 301 | else |
c0b766f1 | 302 | ops->warning(data, "Full inexact backtrace again:\n"); |
ea424055 | 303 | } else |
c0b766f1 AK |
304 | ops->warning(data, "Inexact backtrace:\n"); |
305 | } | |
306 | if (!stack) { | |
307 | unsigned long dummy; | |
308 | stack = &dummy; | |
309 | if (tsk && tsk != current) | |
310 | stack = (unsigned long *)tsk->thread.rsp; | |
b538ed27 JB |
311 | } |
312 | ||
c9ca1ba5 IM |
313 | /* |
314 | * Print function call entries within a stack. 'cond' is the | |
315 | * "end of stackframe" condition, that the 'stack++' | |
316 | * iteration will eventually trigger. | |
317 | */ | |
0a658002 AK |
318 | #define HANDLE_STACK(cond) \ |
319 | do while (cond) { \ | |
1b2f6304 | 320 | unsigned long addr = *stack++; \ |
0a658002 AK |
321 | if (kernel_text_address(addr)) { \ |
322 | /* \ | |
323 | * If the address is either in the text segment of the \ | |
324 | * kernel, or in the region which contains vmalloc'ed \ | |
325 | * memory, it *may* be the address of a calling \ | |
326 | * routine; if so, print it so that someone tracing \ | |
327 | * down the cause of the crash will be able to figure \ | |
328 | * out the call path that was taken. \ | |
329 | */ \ | |
c0b766f1 | 330 | ops->address(data, addr); \ |
0a658002 AK |
331 | } \ |
332 | } while (0) | |
333 | ||
c9ca1ba5 IM |
334 | /* |
335 | * Print function call entries in all stacks, starting at the | |
336 | * current stack address. If the stacks consist of nested | |
337 | * exceptions | |
338 | */ | |
c0b766f1 AK |
339 | for (;;) { |
340 | char *id; | |
0a658002 AK |
341 | unsigned long *estack_end; |
342 | estack_end = in_exception_stack(cpu, (unsigned long)stack, | |
343 | &used, &id); | |
344 | ||
345 | if (estack_end) { | |
c0b766f1 AK |
346 | if (ops->stack(data, id) < 0) |
347 | break; | |
0a658002 | 348 | HANDLE_STACK (stack < estack_end); |
c0b766f1 | 349 | ops->stack(data, "<EOE>"); |
c9ca1ba5 IM |
350 | /* |
351 | * We link to the next stack via the | |
352 | * second-to-last pointer (index -2 to end) in the | |
353 | * exception stack: | |
354 | */ | |
0a658002 AK |
355 | stack = (unsigned long *) estack_end[-2]; |
356 | continue; | |
1da177e4 | 357 | } |
0a658002 AK |
358 | if (irqstack_end) { |
359 | unsigned long *irqstack; | |
360 | irqstack = irqstack_end - | |
361 | (IRQSTACKSIZE - 64) / sizeof(*irqstack); | |
362 | ||
363 | if (stack >= irqstack && stack < irqstack_end) { | |
c0b766f1 AK |
364 | if (ops->stack(data, "IRQ") < 0) |
365 | break; | |
0a658002 | 366 | HANDLE_STACK (stack < irqstack_end); |
c9ca1ba5 IM |
367 | /* |
368 | * We link to the next stack (which would be | |
369 | * the process stack normally) the last | |
370 | * pointer (index -1 to end) in the IRQ stack: | |
371 | */ | |
0a658002 AK |
372 | stack = (unsigned long *) (irqstack_end[-1]); |
373 | irqstack_end = NULL; | |
c0b766f1 | 374 | ops->stack(data, "EOI"); |
0a658002 | 375 | continue; |
1da177e4 | 376 | } |
1da177e4 | 377 | } |
0a658002 | 378 | break; |
1da177e4 | 379 | } |
0a658002 | 380 | |
c9ca1ba5 | 381 | /* |
c0b766f1 | 382 | * This handles the process stack: |
c9ca1ba5 | 383 | */ |
0a658002 AK |
384 | HANDLE_STACK (((long) stack & (THREAD_SIZE-1)) != 0); |
385 | #undef HANDLE_STACK | |
c0b766f1 AK |
386 | } |
387 | EXPORT_SYMBOL(dump_trace); | |
388 | ||
389 | static void | |
390 | print_trace_warning_symbol(void *data, char *msg, unsigned long symbol) | |
391 | { | |
392 | print_symbol(msg, symbol); | |
393 | printk("\n"); | |
394 | } | |
395 | ||
396 | static void print_trace_warning(void *data, char *msg) | |
397 | { | |
398 | printk("%s\n", msg); | |
399 | } | |
400 | ||
401 | static int print_trace_stack(void *data, char *name) | |
402 | { | |
403 | printk(" <%s> ", name); | |
404 | return 0; | |
405 | } | |
3ac94932 | 406 | |
c0b766f1 AK |
407 | static void print_trace_address(void *data, unsigned long addr) |
408 | { | |
409 | printk_address(addr); | |
410 | } | |
411 | ||
412 | static struct stacktrace_ops print_trace_ops = { | |
413 | .warning = print_trace_warning, | |
414 | .warning_symbol = print_trace_warning_symbol, | |
415 | .stack = print_trace_stack, | |
416 | .address = print_trace_address, | |
417 | }; | |
418 | ||
419 | void | |
420 | show_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long *stack) | |
421 | { | |
422 | printk("\nCall Trace:\n"); | |
423 | dump_trace(tsk, regs, stack, &print_trace_ops, NULL); | |
1da177e4 LT |
424 | printk("\n"); |
425 | } | |
426 | ||
c0b766f1 AK |
427 | static void |
428 | _show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long *rsp) | |
1da177e4 LT |
429 | { |
430 | unsigned long *stack; | |
431 | int i; | |
432 | const int cpu = safe_smp_processor_id(); | |
df79efde RT |
433 | unsigned long *irqstack_end = (unsigned long *) (cpu_pda(cpu)->irqstackptr); |
434 | unsigned long *irqstack = (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE); | |
1da177e4 LT |
435 | |
436 | // debugging aid: "show_stack(NULL, NULL);" prints the | |
437 | // back trace for this cpu. | |
438 | ||
439 | if (rsp == NULL) { | |
440 | if (tsk) | |
441 | rsp = (unsigned long *)tsk->thread.rsp; | |
442 | else | |
443 | rsp = (unsigned long *)&rsp; | |
444 | } | |
445 | ||
446 | stack = rsp; | |
447 | for(i=0; i < kstack_depth_to_print; i++) { | |
448 | if (stack >= irqstack && stack <= irqstack_end) { | |
449 | if (stack == irqstack_end) { | |
450 | stack = (unsigned long *) (irqstack_end[-1]); | |
451 | printk(" <EOI> "); | |
452 | } | |
453 | } else { | |
454 | if (((long) stack & (THREAD_SIZE-1)) == 0) | |
455 | break; | |
456 | } | |
457 | if (i && ((i % 4) == 0)) | |
3ac94932 IM |
458 | printk("\n"); |
459 | printk(" %016lx", *stack++); | |
35faa714 | 460 | touch_nmi_watchdog(); |
1da177e4 | 461 | } |
b538ed27 JB |
462 | show_trace(tsk, regs, rsp); |
463 | } | |
464 | ||
465 | void show_stack(struct task_struct *tsk, unsigned long * rsp) | |
466 | { | |
467 | _show_stack(tsk, NULL, rsp); | |
1da177e4 LT |
468 | } |
469 | ||
470 | /* | |
471 | * The architecture-independent dump_stack generator | |
472 | */ | |
473 | void dump_stack(void) | |
474 | { | |
475 | unsigned long dummy; | |
b538ed27 | 476 | show_trace(NULL, NULL, &dummy); |
1da177e4 LT |
477 | } |
478 | ||
479 | EXPORT_SYMBOL(dump_stack); | |
480 | ||
481 | void show_registers(struct pt_regs *regs) | |
482 | { | |
483 | int i; | |
76381fee | 484 | int in_kernel = !user_mode(regs); |
1da177e4 LT |
485 | unsigned long rsp; |
486 | const int cpu = safe_smp_processor_id(); | |
df79efde | 487 | struct task_struct *cur = cpu_pda(cpu)->pcurrent; |
1da177e4 LT |
488 | |
489 | rsp = regs->rsp; | |
490 | ||
491 | printk("CPU %d ", cpu); | |
492 | __show_regs(regs); | |
493 | printk("Process %s (pid: %d, threadinfo %p, task %p)\n", | |
e4f17c43 | 494 | cur->comm, cur->pid, task_thread_info(cur), cur); |
1da177e4 LT |
495 | |
496 | /* | |
497 | * When in-kernel, we also print out the stack and code at the | |
498 | * time of the fault.. | |
499 | */ | |
500 | if (in_kernel) { | |
501 | ||
502 | printk("Stack: "); | |
b538ed27 | 503 | _show_stack(NULL, regs, (unsigned long*)rsp); |
1da177e4 LT |
504 | |
505 | printk("\nCode: "); | |
2b692a87 | 506 | if (regs->rip < PAGE_OFFSET) |
1da177e4 LT |
507 | goto bad; |
508 | ||
2b692a87 | 509 | for (i=0; i<20; i++) { |
1da177e4 | 510 | unsigned char c; |
2b692a87 | 511 | if (__get_user(c, &((unsigned char*)regs->rip)[i])) { |
1da177e4 LT |
512 | bad: |
513 | printk(" Bad RIP value."); | |
514 | break; | |
515 | } | |
516 | printk("%02x ", c); | |
517 | } | |
518 | } | |
519 | printk("\n"); | |
520 | } | |
521 | ||
522 | void handle_BUG(struct pt_regs *regs) | |
523 | { | |
524 | struct bug_frame f; | |
5f1d189f JB |
525 | long len; |
526 | const char *prefix = ""; | |
1da177e4 | 527 | |
76381fee | 528 | if (user_mode(regs)) |
1da177e4 | 529 | return; |
77a75333 | 530 | if (__copy_from_user(&f, (const void __user *) regs->rip, |
1da177e4 LT |
531 | sizeof(struct bug_frame))) |
532 | return; | |
049cdefe | 533 | if (f.filename >= 0 || |
1da177e4 LT |
534 | f.ud2[0] != 0x0f || f.ud2[1] != 0x0b) |
535 | return; | |
5f1d189f JB |
536 | len = __strnlen_user((char *)(long)f.filename, PATH_MAX) - 1; |
537 | if (len < 0 || len >= PATH_MAX) | |
049cdefe | 538 | f.filename = (int)(long)"unmapped filename"; |
5f1d189f JB |
539 | else if (len > 50) { |
540 | f.filename += len - 50; | |
541 | prefix = "..."; | |
542 | } | |
1da177e4 | 543 | printk("----------- [cut here ] --------- [please bite here ] ---------\n"); |
5f1d189f | 544 | printk(KERN_ALERT "Kernel BUG at %s%.50s:%d\n", prefix, (char *)(long)f.filename, f.line); |
1da177e4 LT |
545 | } |
546 | ||
4f60fdf6 | 547 | #ifdef CONFIG_BUG |
1da177e4 LT |
548 | void out_of_line_bug(void) |
549 | { | |
550 | BUG(); | |
551 | } | |
2ee60e17 | 552 | EXPORT_SYMBOL(out_of_line_bug); |
4f60fdf6 | 553 | #endif |
1da177e4 LT |
554 | |
555 | static DEFINE_SPINLOCK(die_lock); | |
556 | static int die_owner = -1; | |
cdc60a4c | 557 | static unsigned int die_nest_count; |
1da177e4 | 558 | |
eddb6fb9 | 559 | unsigned __kprobes long oops_begin(void) |
1da177e4 | 560 | { |
1209140c JB |
561 | int cpu = safe_smp_processor_id(); |
562 | unsigned long flags; | |
563 | ||
564 | /* racy, but better than risking deadlock. */ | |
565 | local_irq_save(flags); | |
1da177e4 LT |
566 | if (!spin_trylock(&die_lock)) { |
567 | if (cpu == die_owner) | |
568 | /* nested oops. should stop eventually */; | |
569 | else | |
1209140c | 570 | spin_lock(&die_lock); |
1da177e4 | 571 | } |
cdc60a4c | 572 | die_nest_count++; |
1209140c | 573 | die_owner = cpu; |
1da177e4 | 574 | console_verbose(); |
1209140c JB |
575 | bust_spinlocks(1); |
576 | return flags; | |
1da177e4 LT |
577 | } |
578 | ||
eddb6fb9 | 579 | void __kprobes oops_end(unsigned long flags) |
1da177e4 LT |
580 | { |
581 | die_owner = -1; | |
1209140c | 582 | bust_spinlocks(0); |
cdc60a4c CM |
583 | die_nest_count--; |
584 | if (die_nest_count) | |
585 | /* We still own the lock */ | |
586 | local_irq_restore(flags); | |
587 | else | |
588 | /* Nest count reaches zero, release the lock. */ | |
589 | spin_unlock_irqrestore(&die_lock, flags); | |
1da177e4 | 590 | if (panic_on_oops) |
012c437d | 591 | panic("Fatal exception"); |
1209140c | 592 | } |
1da177e4 | 593 | |
eddb6fb9 | 594 | void __kprobes __die(const char * str, struct pt_regs * regs, long err) |
1da177e4 LT |
595 | { |
596 | static int die_counter; | |
597 | printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter); | |
598 | #ifdef CONFIG_PREEMPT | |
599 | printk("PREEMPT "); | |
600 | #endif | |
601 | #ifdef CONFIG_SMP | |
602 | printk("SMP "); | |
603 | #endif | |
604 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
605 | printk("DEBUG_PAGEALLOC"); | |
606 | #endif | |
607 | printk("\n"); | |
6e3f3617 | 608 | notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV); |
1da177e4 LT |
609 | show_registers(regs); |
610 | /* Executive summary in case the oops scrolled away */ | |
611 | printk(KERN_ALERT "RIP "); | |
612 | printk_address(regs->rip); | |
613 | printk(" RSP <%016lx>\n", regs->rsp); | |
8bcc5280 VG |
614 | if (kexec_should_crash(current)) |
615 | crash_kexec(regs); | |
1da177e4 LT |
616 | } |
617 | ||
618 | void die(const char * str, struct pt_regs * regs, long err) | |
619 | { | |
1209140c JB |
620 | unsigned long flags = oops_begin(); |
621 | ||
1da177e4 LT |
622 | handle_BUG(regs); |
623 | __die(str, regs, err); | |
1209140c | 624 | oops_end(flags); |
1da177e4 LT |
625 | do_exit(SIGSEGV); |
626 | } | |
1da177e4 | 627 | |
fac58550 | 628 | void __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic) |
1da177e4 | 629 | { |
1209140c JB |
630 | unsigned long flags = oops_begin(); |
631 | ||
1da177e4 LT |
632 | /* |
633 | * We are in trouble anyway, lets at least try | |
634 | * to get a message out. | |
635 | */ | |
636 | printk(str, safe_smp_processor_id()); | |
637 | show_registers(regs); | |
8bcc5280 VG |
638 | if (kexec_should_crash(current)) |
639 | crash_kexec(regs); | |
fac58550 AK |
640 | if (do_panic || panic_on_oops) |
641 | panic("Non maskable interrupt"); | |
1209140c | 642 | oops_end(flags); |
8b1ffe95 CM |
643 | nmi_exit(); |
644 | local_irq_enable(); | |
1da177e4 LT |
645 | do_exit(SIGSEGV); |
646 | } | |
647 | ||
0f2fbdcb PP |
648 | static void __kprobes do_trap(int trapnr, int signr, char *str, |
649 | struct pt_regs * regs, long error_code, | |
650 | siginfo_t *info) | |
1da177e4 | 651 | { |
6e3f3617 JB |
652 | struct task_struct *tsk = current; |
653 | ||
6e3f3617 JB |
654 | tsk->thread.error_code = error_code; |
655 | tsk->thread.trap_no = trapnr; | |
1da177e4 | 656 | |
6e3f3617 | 657 | if (user_mode(regs)) { |
1da177e4 LT |
658 | if (exception_trace && unhandled_signal(tsk, signr)) |
659 | printk(KERN_INFO | |
660 | "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n", | |
661 | tsk->comm, tsk->pid, str, | |
2b692a87 | 662 | regs->rip, regs->rsp, error_code); |
1da177e4 | 663 | |
1da177e4 LT |
664 | if (info) |
665 | force_sig_info(signr, info, tsk); | |
666 | else | |
667 | force_sig(signr, tsk); | |
668 | return; | |
669 | } | |
670 | ||
671 | ||
672 | /* kernel trap */ | |
673 | { | |
674 | const struct exception_table_entry *fixup; | |
675 | fixup = search_exception_tables(regs->rip); | |
2b692a87 | 676 | if (fixup) |
1da177e4 | 677 | regs->rip = fixup->fixup; |
2b692a87 | 678 | else |
1da177e4 LT |
679 | die(str, regs, error_code); |
680 | return; | |
681 | } | |
682 | } | |
683 | ||
684 | #define DO_ERROR(trapnr, signr, str, name) \ | |
685 | asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ | |
686 | { \ | |
687 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ | |
688 | == NOTIFY_STOP) \ | |
689 | return; \ | |
40e59a61 | 690 | conditional_sti(regs); \ |
1da177e4 LT |
691 | do_trap(trapnr, signr, str, regs, error_code, NULL); \ |
692 | } | |
693 | ||
694 | #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ | |
695 | asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ | |
696 | { \ | |
697 | siginfo_t info; \ | |
698 | info.si_signo = signr; \ | |
699 | info.si_errno = 0; \ | |
700 | info.si_code = sicode; \ | |
701 | info.si_addr = (void __user *)siaddr; \ | |
702 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ | |
703 | == NOTIFY_STOP) \ | |
704 | return; \ | |
40e59a61 | 705 | conditional_sti(regs); \ |
1da177e4 LT |
706 | do_trap(trapnr, signr, str, regs, error_code, &info); \ |
707 | } | |
708 | ||
709 | DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip) | |
710 | DO_ERROR( 4, SIGSEGV, "overflow", overflow) | |
711 | DO_ERROR( 5, SIGSEGV, "bounds", bounds) | |
100c0e36 | 712 | DO_ERROR_INFO( 6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->rip) |
1da177e4 LT |
713 | DO_ERROR( 7, SIGSEGV, "device not available", device_not_available) |
714 | DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun) | |
715 | DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS) | |
716 | DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) | |
717 | DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) | |
718 | DO_ERROR(18, SIGSEGV, "reserved", reserved) | |
40e59a61 AK |
719 | |
720 | /* Runs on IST stack */ | |
721 | asmlinkage void do_stack_segment(struct pt_regs *regs, long error_code) | |
722 | { | |
723 | if (notify_die(DIE_TRAP, "stack segment", regs, error_code, | |
724 | 12, SIGBUS) == NOTIFY_STOP) | |
725 | return; | |
726 | preempt_conditional_sti(regs); | |
727 | do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL); | |
728 | preempt_conditional_cli(regs); | |
729 | } | |
eca37c18 JB |
730 | |
731 | asmlinkage void do_double_fault(struct pt_regs * regs, long error_code) | |
732 | { | |
733 | static const char str[] = "double fault"; | |
734 | struct task_struct *tsk = current; | |
735 | ||
736 | /* Return not checked because double check cannot be ignored */ | |
737 | notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV); | |
738 | ||
739 | tsk->thread.error_code = error_code; | |
740 | tsk->thread.trap_no = 8; | |
741 | ||
742 | /* This is always a kernel trap and never fixable (and thus must | |
743 | never return). */ | |
744 | for (;;) | |
745 | die(str, regs, error_code); | |
746 | } | |
1da177e4 | 747 | |
0f2fbdcb PP |
748 | asmlinkage void __kprobes do_general_protection(struct pt_regs * regs, |
749 | long error_code) | |
1da177e4 | 750 | { |
6e3f3617 JB |
751 | struct task_struct *tsk = current; |
752 | ||
1da177e4 LT |
753 | conditional_sti(regs); |
754 | ||
6e3f3617 JB |
755 | tsk->thread.error_code = error_code; |
756 | tsk->thread.trap_no = 13; | |
1da177e4 | 757 | |
6e3f3617 | 758 | if (user_mode(regs)) { |
1da177e4 LT |
759 | if (exception_trace && unhandled_signal(tsk, SIGSEGV)) |
760 | printk(KERN_INFO | |
761 | "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n", | |
762 | tsk->comm, tsk->pid, | |
2b692a87 | 763 | regs->rip, regs->rsp, error_code); |
1da177e4 | 764 | |
1da177e4 LT |
765 | force_sig(SIGSEGV, tsk); |
766 | return; | |
767 | } | |
768 | ||
769 | /* kernel gp */ | |
770 | { | |
771 | const struct exception_table_entry *fixup; | |
772 | fixup = search_exception_tables(regs->rip); | |
773 | if (fixup) { | |
774 | regs->rip = fixup->fixup; | |
775 | return; | |
776 | } | |
777 | if (notify_die(DIE_GPF, "general protection fault", regs, | |
778 | error_code, 13, SIGSEGV) == NOTIFY_STOP) | |
779 | return; | |
780 | die("general protection fault", regs, error_code); | |
781 | } | |
782 | } | |
783 | ||
eddb6fb9 AK |
784 | static __kprobes void |
785 | mem_parity_error(unsigned char reason, struct pt_regs * regs) | |
1da177e4 | 786 | { |
c41c5cd3 DZ |
787 | printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n", |
788 | reason); | |
789 | printk(KERN_EMERG "You probably have a hardware problem with your " | |
790 | "RAM chips\n"); | |
791 | ||
8da5adda | 792 | if (panic_on_unrecovered_nmi) |
c41c5cd3 DZ |
793 | panic("NMI: Not continuing"); |
794 | ||
795 | printk(KERN_EMERG "Dazed and confused, but trying to continue\n"); | |
1da177e4 LT |
796 | |
797 | /* Clear and disable the memory parity error line. */ | |
798 | reason = (reason & 0xf) | 4; | |
799 | outb(reason, 0x61); | |
800 | } | |
801 | ||
eddb6fb9 AK |
802 | static __kprobes void |
803 | io_check_error(unsigned char reason, struct pt_regs * regs) | |
1da177e4 LT |
804 | { |
805 | printk("NMI: IOCK error (debug interrupt?)\n"); | |
806 | show_registers(regs); | |
807 | ||
808 | /* Re-enable the IOCK line, wait for a few seconds */ | |
809 | reason = (reason & 0xf) | 8; | |
810 | outb(reason, 0x61); | |
811 | mdelay(2000); | |
812 | reason &= ~8; | |
813 | outb(reason, 0x61); | |
814 | } | |
815 | ||
eddb6fb9 AK |
816 | static __kprobes void |
817 | unknown_nmi_error(unsigned char reason, struct pt_regs * regs) | |
c41c5cd3 DZ |
818 | { |
819 | printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n", | |
820 | reason); | |
821 | printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n"); | |
8da5adda DZ |
822 | |
823 | if (panic_on_unrecovered_nmi) | |
c41c5cd3 | 824 | panic("NMI: Not continuing"); |
8da5adda | 825 | |
c41c5cd3 | 826 | printk(KERN_EMERG "Dazed and confused, but trying to continue\n"); |
1da177e4 LT |
827 | } |
828 | ||
6fefb0d1 AK |
829 | /* Runs on IST stack. This code must keep interrupts off all the time. |
830 | Nested NMIs are prevented by the CPU. */ | |
eddb6fb9 | 831 | asmlinkage __kprobes void default_do_nmi(struct pt_regs *regs) |
1da177e4 LT |
832 | { |
833 | unsigned char reason = 0; | |
76e4f660 AR |
834 | int cpu; |
835 | ||
836 | cpu = smp_processor_id(); | |
1da177e4 LT |
837 | |
838 | /* Only the BSP gets external NMIs from the system. */ | |
76e4f660 | 839 | if (!cpu) |
1da177e4 LT |
840 | reason = get_nmi_reason(); |
841 | ||
842 | if (!(reason & 0xc0)) { | |
6e3f3617 | 843 | if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT) |
1da177e4 LT |
844 | == NOTIFY_STOP) |
845 | return; | |
1da177e4 LT |
846 | /* |
847 | * Ok, so this is none of the documented NMI sources, | |
848 | * so it must be the NMI watchdog. | |
849 | */ | |
3adbbcce | 850 | if (nmi_watchdog_tick(regs,reason)) |
1da177e4 | 851 | return; |
3adbbcce | 852 | if (!do_nmi_callback(regs,cpu)) |
3adbbcce DZ |
853 | unknown_nmi_error(reason, regs); |
854 | ||
1da177e4 LT |
855 | return; |
856 | } | |
6e3f3617 | 857 | if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP) |
1da177e4 LT |
858 | return; |
859 | ||
860 | /* AK: following checks seem to be broken on modern chipsets. FIXME */ | |
861 | ||
862 | if (reason & 0x80) | |
863 | mem_parity_error(reason, regs); | |
864 | if (reason & 0x40) | |
865 | io_check_error(reason, regs); | |
866 | } | |
867 | ||
b556b35e | 868 | /* runs on IST stack. */ |
0f2fbdcb | 869 | asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code) |
1da177e4 LT |
870 | { |
871 | if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) { | |
872 | return; | |
873 | } | |
40e59a61 | 874 | preempt_conditional_sti(regs); |
1da177e4 | 875 | do_trap(3, SIGTRAP, "int3", regs, error_code, NULL); |
40e59a61 | 876 | preempt_conditional_cli(regs); |
1da177e4 LT |
877 | } |
878 | ||
6fefb0d1 AK |
879 | /* Help handler running on IST stack to switch back to user stack |
880 | for scheduling or signal handling. The actual stack switch is done in | |
881 | entry.S */ | |
eddb6fb9 | 882 | asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) |
6fefb0d1 AK |
883 | { |
884 | struct pt_regs *regs = eregs; | |
885 | /* Did already sync */ | |
886 | if (eregs == (struct pt_regs *)eregs->rsp) | |
887 | ; | |
888 | /* Exception from user space */ | |
76381fee | 889 | else if (user_mode(eregs)) |
bb049232 | 890 | regs = task_pt_regs(current); |
6fefb0d1 AK |
891 | /* Exception from kernel and interrupts are enabled. Move to |
892 | kernel process stack. */ | |
893 | else if (eregs->eflags & X86_EFLAGS_IF) | |
894 | regs = (struct pt_regs *)(eregs->rsp -= sizeof(struct pt_regs)); | |
895 | if (eregs != regs) | |
896 | *regs = *eregs; | |
897 | return regs; | |
898 | } | |
899 | ||
1da177e4 | 900 | /* runs on IST stack. */ |
0f2fbdcb PP |
901 | asmlinkage void __kprobes do_debug(struct pt_regs * regs, |
902 | unsigned long error_code) | |
1da177e4 | 903 | { |
1da177e4 LT |
904 | unsigned long condition; |
905 | struct task_struct *tsk = current; | |
906 | siginfo_t info; | |
907 | ||
e9129e56 | 908 | get_debugreg(condition, 6); |
1da177e4 LT |
909 | |
910 | if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code, | |
daeeafec | 911 | SIGTRAP) == NOTIFY_STOP) |
6fefb0d1 | 912 | return; |
daeeafec | 913 | |
a65d17c9 | 914 | preempt_conditional_sti(regs); |
1da177e4 LT |
915 | |
916 | /* Mask out spurious debug traps due to lazy DR7 setting */ | |
917 | if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) { | |
918 | if (!tsk->thread.debugreg7) { | |
919 | goto clear_dr7; | |
920 | } | |
921 | } | |
922 | ||
923 | tsk->thread.debugreg6 = condition; | |
924 | ||
925 | /* Mask out spurious TF errors due to lazy TF clearing */ | |
daeeafec | 926 | if (condition & DR_STEP) { |
1da177e4 LT |
927 | /* |
928 | * The TF error should be masked out only if the current | |
929 | * process is not traced and if the TRAP flag has been set | |
930 | * previously by a tracing process (condition detected by | |
931 | * the PT_DTRACE flag); remember that the i386 TRAP flag | |
932 | * can be modified by the process itself in user mode, | |
933 | * allowing programs to debug themselves without the ptrace() | |
934 | * interface. | |
935 | */ | |
76381fee | 936 | if (!user_mode(regs)) |
1da177e4 | 937 | goto clear_TF_reenable; |
be61bff7 AK |
938 | /* |
939 | * Was the TF flag set by a debugger? If so, clear it now, | |
940 | * so that register information is correct. | |
941 | */ | |
942 | if (tsk->ptrace & PT_DTRACE) { | |
943 | regs->eflags &= ~TF_MASK; | |
944 | tsk->ptrace &= ~PT_DTRACE; | |
945 | } | |
1da177e4 LT |
946 | } |
947 | ||
948 | /* Ok, finally something we can handle */ | |
949 | tsk->thread.trap_no = 1; | |
950 | tsk->thread.error_code = error_code; | |
951 | info.si_signo = SIGTRAP; | |
952 | info.si_errno = 0; | |
953 | info.si_code = TRAP_BRKPT; | |
01b8faae JB |
954 | info.si_addr = user_mode(regs) ? (void __user *)regs->rip : NULL; |
955 | force_sig_info(SIGTRAP, &info, tsk); | |
1da177e4 | 956 | |
1da177e4 | 957 | clear_dr7: |
e9129e56 | 958 | set_debugreg(0UL, 7); |
a65d17c9 | 959 | preempt_conditional_cli(regs); |
6fefb0d1 | 960 | return; |
1da177e4 LT |
961 | |
962 | clear_TF_reenable: | |
963 | set_tsk_thread_flag(tsk, TIF_SINGLESTEP); | |
1da177e4 | 964 | regs->eflags &= ~TF_MASK; |
a65d17c9 | 965 | preempt_conditional_cli(regs); |
1da177e4 LT |
966 | } |
967 | ||
6e3f3617 | 968 | static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr) |
1da177e4 LT |
969 | { |
970 | const struct exception_table_entry *fixup; | |
971 | fixup = search_exception_tables(regs->rip); | |
972 | if (fixup) { | |
973 | regs->rip = fixup->fixup; | |
974 | return 1; | |
975 | } | |
6e3f3617 | 976 | notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE); |
3a848f63 | 977 | /* Illegal floating point operation in the kernel */ |
6e3f3617 | 978 | current->thread.trap_no = trapnr; |
1da177e4 | 979 | die(str, regs, 0); |
1da177e4 LT |
980 | return 0; |
981 | } | |
982 | ||
983 | /* | |
984 | * Note that we play around with the 'TS' bit in an attempt to get | |
985 | * the correct behaviour even in the presence of the asynchronous | |
986 | * IRQ13 behaviour | |
987 | */ | |
988 | asmlinkage void do_coprocessor_error(struct pt_regs *regs) | |
989 | { | |
990 | void __user *rip = (void __user *)(regs->rip); | |
991 | struct task_struct * task; | |
992 | siginfo_t info; | |
993 | unsigned short cwd, swd; | |
994 | ||
995 | conditional_sti(regs); | |
76381fee | 996 | if (!user_mode(regs) && |
6e3f3617 | 997 | kernel_math_error(regs, "kernel x87 math error", 16)) |
1da177e4 LT |
998 | return; |
999 | ||
1000 | /* | |
1001 | * Save the info for the exception handler and clear the error. | |
1002 | */ | |
1003 | task = current; | |
1004 | save_init_fpu(task); | |
1005 | task->thread.trap_no = 16; | |
1006 | task->thread.error_code = 0; | |
1007 | info.si_signo = SIGFPE; | |
1008 | info.si_errno = 0; | |
1009 | info.si_code = __SI_FAULT; | |
1010 | info.si_addr = rip; | |
1011 | /* | |
1012 | * (~cwd & swd) will mask out exceptions that are not set to unmasked | |
1013 | * status. 0x3f is the exception bits in these regs, 0x200 is the | |
1014 | * C1 reg you need in case of a stack fault, 0x040 is the stack | |
1015 | * fault bit. We should only be taking one exception at a time, | |
1016 | * so if this combination doesn't produce any single exception, | |
1017 | * then we have a bad program that isn't synchronizing its FPU usage | |
1018 | * and it will suffer the consequences since we won't be able to | |
1019 | * fully reproduce the context of the exception | |
1020 | */ | |
1021 | cwd = get_fpu_cwd(task); | |
1022 | swd = get_fpu_swd(task); | |
ff347b22 | 1023 | switch (swd & ~cwd & 0x3f) { |
1da177e4 LT |
1024 | case 0x000: |
1025 | default: | |
1026 | break; | |
1027 | case 0x001: /* Invalid Op */ | |
ff347b22 CE |
1028 | /* |
1029 | * swd & 0x240 == 0x040: Stack Underflow | |
1030 | * swd & 0x240 == 0x240: Stack Overflow | |
1031 | * User must clear the SF bit (0x40) if set | |
1032 | */ | |
1da177e4 LT |
1033 | info.si_code = FPE_FLTINV; |
1034 | break; | |
1035 | case 0x002: /* Denormalize */ | |
1036 | case 0x010: /* Underflow */ | |
1037 | info.si_code = FPE_FLTUND; | |
1038 | break; | |
1039 | case 0x004: /* Zero Divide */ | |
1040 | info.si_code = FPE_FLTDIV; | |
1041 | break; | |
1042 | case 0x008: /* Overflow */ | |
1043 | info.si_code = FPE_FLTOVF; | |
1044 | break; | |
1045 | case 0x020: /* Precision */ | |
1046 | info.si_code = FPE_FLTRES; | |
1047 | break; | |
1048 | } | |
1049 | force_sig_info(SIGFPE, &info, task); | |
1050 | } | |
1051 | ||
1052 | asmlinkage void bad_intr(void) | |
1053 | { | |
1054 | printk("bad interrupt"); | |
1055 | } | |
1056 | ||
1057 | asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs) | |
1058 | { | |
1059 | void __user *rip = (void __user *)(regs->rip); | |
1060 | struct task_struct * task; | |
1061 | siginfo_t info; | |
1062 | unsigned short mxcsr; | |
1063 | ||
1064 | conditional_sti(regs); | |
76381fee | 1065 | if (!user_mode(regs) && |
6e3f3617 | 1066 | kernel_math_error(regs, "kernel simd math error", 19)) |
1da177e4 LT |
1067 | return; |
1068 | ||
1069 | /* | |
1070 | * Save the info for the exception handler and clear the error. | |
1071 | */ | |
1072 | task = current; | |
1073 | save_init_fpu(task); | |
1074 | task->thread.trap_no = 19; | |
1075 | task->thread.error_code = 0; | |
1076 | info.si_signo = SIGFPE; | |
1077 | info.si_errno = 0; | |
1078 | info.si_code = __SI_FAULT; | |
1079 | info.si_addr = rip; | |
1080 | /* | |
1081 | * The SIMD FPU exceptions are handled a little differently, as there | |
1082 | * is only a single status/control register. Thus, to determine which | |
1083 | * unmasked exception was caught we must mask the exception mask bits | |
1084 | * at 0x1f80, and then use these to mask the exception bits at 0x3f. | |
1085 | */ | |
1086 | mxcsr = get_fpu_mxcsr(task); | |
1087 | switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) { | |
1088 | case 0x000: | |
1089 | default: | |
1090 | break; | |
1091 | case 0x001: /* Invalid Op */ | |
1092 | info.si_code = FPE_FLTINV; | |
1093 | break; | |
1094 | case 0x002: /* Denormalize */ | |
1095 | case 0x010: /* Underflow */ | |
1096 | info.si_code = FPE_FLTUND; | |
1097 | break; | |
1098 | case 0x004: /* Zero Divide */ | |
1099 | info.si_code = FPE_FLTDIV; | |
1100 | break; | |
1101 | case 0x008: /* Overflow */ | |
1102 | info.si_code = FPE_FLTOVF; | |
1103 | break; | |
1104 | case 0x020: /* Precision */ | |
1105 | info.si_code = FPE_FLTRES; | |
1106 | break; | |
1107 | } | |
1108 | force_sig_info(SIGFPE, &info, task); | |
1109 | } | |
1110 | ||
1111 | asmlinkage void do_spurious_interrupt_bug(struct pt_regs * regs) | |
1112 | { | |
1113 | } | |
1114 | ||
1115 | asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void) | |
89b831ef JS |
1116 | { |
1117 | } | |
1118 | ||
1119 | asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void) | |
1da177e4 LT |
1120 | { |
1121 | } | |
1122 | ||
1123 | /* | |
1124 | * 'math_state_restore()' saves the current math information in the | |
1125 | * old math state array, and gets the new ones from the current task | |
1126 | * | |
1127 | * Careful.. There are problems with IBM-designed IRQ13 behaviour. | |
1128 | * Don't touch unless you *really* know how it works. | |
1129 | */ | |
1130 | asmlinkage void math_state_restore(void) | |
1131 | { | |
1132 | struct task_struct *me = current; | |
1133 | clts(); /* Allow maths ops (or we recurse) */ | |
1134 | ||
1135 | if (!used_math()) | |
1136 | init_fpu(me); | |
1137 | restore_fpu_checking(&me->thread.i387.fxsave); | |
e4f17c43 | 1138 | task_thread_info(me)->status |= TS_USEDFPU; |
1da177e4 LT |
1139 | } |
1140 | ||
1da177e4 LT |
1141 | void __init trap_init(void) |
1142 | { | |
1143 | set_intr_gate(0,÷_error); | |
1144 | set_intr_gate_ist(1,&debug,DEBUG_STACK); | |
1145 | set_intr_gate_ist(2,&nmi,NMI_STACK); | |
b556b35e | 1146 | set_system_gate_ist(3,&int3,DEBUG_STACK); /* int3 can be called from all */ |
0a521588 JB |
1147 | set_system_gate(4,&overflow); /* int4 can be called from all */ |
1148 | set_intr_gate(5,&bounds); | |
1da177e4 LT |
1149 | set_intr_gate(6,&invalid_op); |
1150 | set_intr_gate(7,&device_not_available); | |
1151 | set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK); | |
1152 | set_intr_gate(9,&coprocessor_segment_overrun); | |
1153 | set_intr_gate(10,&invalid_TSS); | |
1154 | set_intr_gate(11,&segment_not_present); | |
1155 | set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK); | |
1156 | set_intr_gate(13,&general_protection); | |
1157 | set_intr_gate(14,&page_fault); | |
1158 | set_intr_gate(15,&spurious_interrupt_bug); | |
1159 | set_intr_gate(16,&coprocessor_error); | |
1160 | set_intr_gate(17,&alignment_check); | |
1161 | #ifdef CONFIG_X86_MCE | |
1162 | set_intr_gate_ist(18,&machine_check, MCE_STACK); | |
1163 | #endif | |
1164 | set_intr_gate(19,&simd_coprocessor_error); | |
1165 | ||
1166 | #ifdef CONFIG_IA32_EMULATION | |
1167 | set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall); | |
1168 | #endif | |
1169 | ||
1da177e4 LT |
1170 | /* |
1171 | * Should be a barrier for any external CPU state. | |
1172 | */ | |
1173 | cpu_init(); | |
1174 | } | |
1175 | ||
1176 | ||
2c8c0e6b | 1177 | static int __init oops_setup(char *s) |
1da177e4 | 1178 | { |
2c8c0e6b AK |
1179 | if (!s) |
1180 | return -EINVAL; | |
1181 | if (!strcmp(s, "panic")) | |
1182 | panic_on_oops = 1; | |
1183 | return 0; | |
1da177e4 | 1184 | } |
2c8c0e6b | 1185 | early_param("oops", oops_setup); |
1da177e4 LT |
1186 | |
1187 | static int __init kstack_setup(char *s) | |
1188 | { | |
2c8c0e6b AK |
1189 | if (!s) |
1190 | return -EINVAL; | |
1da177e4 | 1191 | kstack_depth_to_print = simple_strtoul(s,NULL,0); |
2c8c0e6b | 1192 | return 0; |
1da177e4 | 1193 | } |
2c8c0e6b | 1194 | early_param("kstack", kstack_setup); |
1da177e4 | 1195 | |
ea424055 | 1196 | #ifdef CONFIG_STACK_UNWIND |
c33bd9aa JB |
1197 | static int __init call_trace_setup(char *s) |
1198 | { | |
2c8c0e6b AK |
1199 | if (!s) |
1200 | return -EINVAL; | |
c33bd9aa JB |
1201 | if (strcmp(s, "old") == 0) |
1202 | call_trace = -1; | |
1203 | else if (strcmp(s, "both") == 0) | |
1204 | call_trace = 0; | |
b13761ec | 1205 | else if (strcmp(s, "newfallback") == 0) |
c33bd9aa | 1206 | call_trace = 1; |
b13761ec AK |
1207 | else if (strcmp(s, "new") == 0) |
1208 | call_trace = 2; | |
2c8c0e6b | 1209 | return 0; |
c33bd9aa | 1210 | } |
2c8c0e6b | 1211 | early_param("call_trace", call_trace_setup); |
ea424055 | 1212 | #endif |