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authorAlexander van Heukelum <heukelum@fastmail.fm>2008-09-30 07:12:15 -0400
committerIngo Molnar <mingo@elte.hu>2008-10-13 04:33:17 -0400
commit6fcbede3fdfbd83d8de97296286f5a9ff5a8f371 (patch)
treec65eceb4a1c023a17a7e5f2474ebadb038072c5f /arch
parent2bc5f927d489f9e47b6fa71f323b653e8ec81782 (diff)
x86_64: split out dumpstack code from traps_64.c
The dumpstack code is logically quite independent from the hardware traps. Split it out into its own file. Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/Makefile4
-rw-r--r--arch/x86/kernel/dumpstack_64.c565
-rw-r--r--arch/x86/kernel/traps_64.c545
3 files changed, 567 insertions, 547 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index d5bde5d8c2b6..de63fed9fae8 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -23,12 +23,12 @@ CFLAGS_hpet.o := $(nostackp)
23CFLAGS_tsc.o := $(nostackp) 23CFLAGS_tsc.o := $(nostackp)
24 24
25obj-y := process_$(BITS).o signal_$(BITS).o entry_$(BITS).o 25obj-y := process_$(BITS).o signal_$(BITS).o entry_$(BITS).o
26obj-y += traps_$(BITS).o irq_$(BITS).o 26obj-y += traps_$(BITS).o irq_$(BITS).o dumpstack_$(BITS).o
27obj-y += time_$(BITS).o ioport.o ldt.o 27obj-y += time_$(BITS).o ioport.o ldt.o
28obj-y += setup.o i8259.o irqinit_$(BITS).o setup_percpu.o 28obj-y += setup.o i8259.o irqinit_$(BITS).o setup_percpu.o
29obj-$(CONFIG_X86_VISWS) += visws_quirks.o 29obj-$(CONFIG_X86_VISWS) += visws_quirks.o
30obj-$(CONFIG_X86_32) += probe_roms_32.o 30obj-$(CONFIG_X86_32) += probe_roms_32.o
31obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o dumpstack_32.o 31obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o
32obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o 32obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o
33obj-$(CONFIG_X86_64) += syscall_64.o vsyscall_64.o 33obj-$(CONFIG_X86_64) += syscall_64.o vsyscall_64.o
34obj-y += bootflag.o e820.o 34obj-y += bootflag.o e820.o
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
new file mode 100644
index 000000000000..6f1505074db0
--- /dev/null
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -0,0 +1,565 @@
1/*
2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
4 */
5#include <linux/kallsyms.h>
6#include <linux/kprobes.h>
7#include <linux/uaccess.h>
8#include <linux/utsname.h>
9#include <linux/hardirq.h>
10#include <linux/kdebug.h>
11#include <linux/module.h>
12#include <linux/ptrace.h>
13#include <linux/kexec.h>
14#include <linux/bug.h>
15#include <linux/nmi.h>
16
17#include <asm/stacktrace.h>
18
19int panic_on_unrecovered_nmi;
20int kstack_depth_to_print = 12;
21static unsigned int code_bytes = 64;
22static int die_counter;
23
24void printk_address(unsigned long address, int reliable)
25{
26 printk(" [<%016lx>] %s%pS\n",
27 address, reliable ? "" : "? ", (void *) address);
28}
29
30static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
31 unsigned *usedp, char **idp)
32{
33 static char ids[][8] = {
34 [DEBUG_STACK - 1] = "#DB",
35 [NMI_STACK - 1] = "NMI",
36 [DOUBLEFAULT_STACK - 1] = "#DF",
37 [STACKFAULT_STACK - 1] = "#SS",
38 [MCE_STACK - 1] = "#MC",
39#if DEBUG_STKSZ > EXCEPTION_STKSZ
40 [N_EXCEPTION_STACKS ...
41 N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
42#endif
43 };
44 unsigned k;
45
46 /*
47 * Iterate over all exception stacks, and figure out whether
48 * 'stack' is in one of them:
49 */
50 for (k = 0; k < N_EXCEPTION_STACKS; k++) {
51 unsigned long end = per_cpu(orig_ist, cpu).ist[k];
52 /*
53 * Is 'stack' above this exception frame's end?
54 * If yes then skip to the next frame.
55 */
56 if (stack >= end)
57 continue;
58 /*
59 * Is 'stack' above this exception frame's start address?
60 * If yes then we found the right frame.
61 */
62 if (stack >= end - EXCEPTION_STKSZ) {
63 /*
64 * Make sure we only iterate through an exception
65 * stack once. If it comes up for the second time
66 * then there's something wrong going on - just
67 * break out and return NULL:
68 */
69 if (*usedp & (1U << k))
70 break;
71 *usedp |= 1U << k;
72 *idp = ids[k];
73 return (unsigned long *)end;
74 }
75 /*
76 * If this is a debug stack, and if it has a larger size than
77 * the usual exception stacks, then 'stack' might still
78 * be within the lower portion of the debug stack:
79 */
80#if DEBUG_STKSZ > EXCEPTION_STKSZ
81 if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
82 unsigned j = N_EXCEPTION_STACKS - 1;
83
84 /*
85 * Black magic. A large debug stack is composed of
86 * multiple exception stack entries, which we
87 * iterate through now. Dont look:
88 */
89 do {
90 ++j;
91 end -= EXCEPTION_STKSZ;
92 ids[j][4] = '1' + (j - N_EXCEPTION_STACKS);
93 } while (stack < end - EXCEPTION_STKSZ);
94 if (*usedp & (1U << j))
95 break;
96 *usedp |= 1U << j;
97 *idp = ids[j];
98 return (unsigned long *)end;
99 }
100#endif
101 }
102 return NULL;
103}
104
105/*
106 * x86-64 can have up to three kernel stacks:
107 * process stack
108 * interrupt stack
109 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
110 */
111
112static inline int valid_stack_ptr(struct thread_info *tinfo,
113 void *p, unsigned int size, void *end)
114{
115 void *t = tinfo;
116 if (end) {
117 if (p < end && p >= (end-THREAD_SIZE))
118 return 1;
119 else
120 return 0;
121 }
122 return p > t && p < t + THREAD_SIZE - size;
123}
124
125/* The form of the top of the frame on the stack */
126struct stack_frame {
127 struct stack_frame *next_frame;
128 unsigned long return_address;
129};
130
131static inline unsigned long
132print_context_stack(struct thread_info *tinfo,
133 unsigned long *stack, unsigned long bp,
134 const struct stacktrace_ops *ops, void *data,
135 unsigned long *end)
136{
137 struct stack_frame *frame = (struct stack_frame *)bp;
138
139 while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
140 unsigned long addr;
141
142 addr = *stack;
143 if (__kernel_text_address(addr)) {
144 if ((unsigned long) stack == bp + 8) {
145 ops->address(data, addr, 1);
146 frame = frame->next_frame;
147 bp = (unsigned long) frame;
148 } else {
149 ops->address(data, addr, bp == 0);
150 }
151 }
152 stack++;
153 }
154 return bp;
155}
156
157void dump_trace(struct task_struct *task, struct pt_regs *regs,
158 unsigned long *stack, unsigned long bp,
159 const struct stacktrace_ops *ops, void *data)
160{
161 const unsigned cpu = get_cpu();
162 unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr;
163 unsigned used = 0;
164 struct thread_info *tinfo;
165
166 if (!task)
167 task = current;
168
169 if (!stack) {
170 unsigned long dummy;
171 stack = &dummy;
172 if (task && task != current)
173 stack = (unsigned long *)task->thread.sp;
174 }
175
176#ifdef CONFIG_FRAME_POINTER
177 if (!bp) {
178 if (task == current) {
179 /* Grab bp right from our regs */
180 asm("movq %%rbp, %0" : "=r" (bp) : );
181 } else {
182 /* bp is the last reg pushed by switch_to */
183 bp = *(unsigned long *) task->thread.sp;
184 }
185 }
186#endif
187
188 /*
189 * Print function call entries in all stacks, starting at the
190 * current stack address. If the stacks consist of nested
191 * exceptions
192 */
193 tinfo = task_thread_info(task);
194 for (;;) {
195 char *id;
196 unsigned long *estack_end;
197 estack_end = in_exception_stack(cpu, (unsigned long)stack,
198 &used, &id);
199
200 if (estack_end) {
201 if (ops->stack(data, id) < 0)
202 break;
203
204 bp = print_context_stack(tinfo, stack, bp, ops,
205 data, estack_end);
206 ops->stack(data, "<EOE>");
207 /*
208 * We link to the next stack via the
209 * second-to-last pointer (index -2 to end) in the
210 * exception stack:
211 */
212 stack = (unsigned long *) estack_end[-2];
213 continue;
214 }
215 if (irqstack_end) {
216 unsigned long *irqstack;
217 irqstack = irqstack_end -
218 (IRQSTACKSIZE - 64) / sizeof(*irqstack);
219
220 if (stack >= irqstack && stack < irqstack_end) {
221 if (ops->stack(data, "IRQ") < 0)
222 break;
223 bp = print_context_stack(tinfo, stack, bp,
224 ops, data, irqstack_end);
225 /*
226 * We link to the next stack (which would be
227 * the process stack normally) the last
228 * pointer (index -1 to end) in the IRQ stack:
229 */
230 stack = (unsigned long *) (irqstack_end[-1]);
231 irqstack_end = NULL;
232 ops->stack(data, "EOI");
233 continue;
234 }
235 }
236 break;
237 }
238
239 /*
240 * This handles the process stack:
241 */
242 bp = print_context_stack(tinfo, stack, bp, ops, data, NULL);
243 put_cpu();
244}
245EXPORT_SYMBOL(dump_trace);
246
247static void
248print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
249{
250 print_symbol(msg, symbol);
251 printk("\n");
252}
253
254static void print_trace_warning(void *data, char *msg)
255{
256 printk("%s\n", msg);
257}
258
259static int print_trace_stack(void *data, char *name)
260{
261 printk(" <%s> ", name);
262 return 0;
263}
264
265static void print_trace_address(void *data, unsigned long addr, int reliable)
266{
267 touch_nmi_watchdog();
268 printk_address(addr, reliable);
269}
270
271static const struct stacktrace_ops print_trace_ops = {
272 .warning = print_trace_warning,
273 .warning_symbol = print_trace_warning_symbol,
274 .stack = print_trace_stack,
275 .address = print_trace_address,
276};
277
278static void
279show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
280 unsigned long *stack, unsigned long bp, char *log_lvl)
281{
282 printk("Call Trace:\n");
283 dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
284}
285
286void show_trace(struct task_struct *task, struct pt_regs *regs,
287 unsigned long *stack, unsigned long bp)
288{
289 show_trace_log_lvl(task, regs, stack, bp, "");
290}
291
292static void
293show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
294 unsigned long *sp, unsigned long bp, char *log_lvl)
295{
296 unsigned long *stack;
297 int i;
298 const int cpu = smp_processor_id();
299 unsigned long *irqstack_end =
300 (unsigned long *) (cpu_pda(cpu)->irqstackptr);
301 unsigned long *irqstack =
302 (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE);
303
304 /*
305 * debugging aid: "show_stack(NULL, NULL);" prints the
306 * back trace for this cpu.
307 */
308
309 if (sp == NULL) {
310 if (task)
311 sp = (unsigned long *)task->thread.sp;
312 else
313 sp = (unsigned long *)&sp;
314 }
315
316 stack = sp;
317 for (i = 0; i < kstack_depth_to_print; i++) {
318 if (stack >= irqstack && stack <= irqstack_end) {
319 if (stack == irqstack_end) {
320 stack = (unsigned long *) (irqstack_end[-1]);
321 printk(" <EOI> ");
322 }
323 } else {
324 if (((long) stack & (THREAD_SIZE-1)) == 0)
325 break;
326 }
327 if (i && ((i % 4) == 0))
328 printk("\n");
329 printk(" %016lx", *stack++);
330 touch_nmi_watchdog();
331 }
332 printk("\n");
333 show_trace_log_lvl(task, regs, sp, bp, log_lvl);
334}
335
336void show_stack(struct task_struct *task, unsigned long *sp)
337{
338 show_stack_log_lvl(task, NULL, sp, 0, "");
339}
340
341/*
342 * The architecture-independent dump_stack generator
343 */
344void dump_stack(void)
345{
346 unsigned long bp = 0;
347 unsigned long stack;
348
349#ifdef CONFIG_FRAME_POINTER
350 if (!bp)
351 asm("movq %%rbp, %0" : "=r" (bp) : );
352#endif
353
354 printk("Pid: %d, comm: %.20s %s %s %.*s\n",
355 current->pid, current->comm, print_tainted(),
356 init_utsname()->release,
357 (int)strcspn(init_utsname()->version, " "),
358 init_utsname()->version);
359 show_trace(NULL, NULL, &stack, bp);
360}
361EXPORT_SYMBOL(dump_stack);
362
363void show_registers(struct pt_regs *regs)
364{
365 int i;
366 unsigned long sp;
367 const int cpu = smp_processor_id();
368 struct task_struct *cur = cpu_pda(cpu)->pcurrent;
369
370 sp = regs->sp;
371 printk("CPU %d ", cpu);
372 __show_regs(regs, 1);
373 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
374 cur->comm, cur->pid, task_thread_info(cur), cur);
375
376 /*
377 * When in-kernel, we also print out the stack and code at the
378 * time of the fault..
379 */
380 if (!user_mode(regs)) {
381 unsigned int code_prologue = code_bytes * 43 / 64;
382 unsigned int code_len = code_bytes;
383 unsigned char c;
384 u8 *ip;
385
386 printk("Stack: ");
387 show_stack_log_lvl(NULL, regs, (unsigned long *)sp,
388 regs->bp, "");
389
390 printk(KERN_EMERG "Code: ");
391
392 ip = (u8 *)regs->ip - code_prologue;
393 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
394 /* try starting at RIP */
395 ip = (u8 *)regs->ip;
396 code_len = code_len - code_prologue + 1;
397 }
398 for (i = 0; i < code_len; i++, ip++) {
399 if (ip < (u8 *)PAGE_OFFSET ||
400 probe_kernel_address(ip, c)) {
401 printk(" Bad RIP value.");
402 break;
403 }
404 if (ip == (u8 *)regs->ip)
405 printk("<%02x> ", c);
406 else
407 printk("%02x ", c);
408 }
409 }
410 printk("\n");
411}
412
413int is_valid_bugaddr(unsigned long ip)
414{
415 unsigned short ud2;
416
417 if (__copy_from_user(&ud2, (const void __user *) ip, sizeof(ud2)))
418 return 0;
419
420 return ud2 == 0x0b0f;
421}
422
423static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
424static int die_owner = -1;
425static unsigned int die_nest_count;
426
427unsigned __kprobes long oops_begin(void)
428{
429 int cpu;
430 unsigned long flags;
431
432 oops_enter();
433
434 /* racy, but better than risking deadlock. */
435 raw_local_irq_save(flags);
436 cpu = smp_processor_id();
437 if (!__raw_spin_trylock(&die_lock)) {
438 if (cpu == die_owner)
439 /* nested oops. should stop eventually */;
440 else
441 __raw_spin_lock(&die_lock);
442 }
443 die_nest_count++;
444 die_owner = cpu;
445 console_verbose();
446 bust_spinlocks(1);
447 return flags;
448}
449
450void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
451{
452 die_owner = -1;
453 bust_spinlocks(0);
454 die_nest_count--;
455 if (!die_nest_count)
456 /* Nest count reaches zero, release the lock. */
457 __raw_spin_unlock(&die_lock);
458 raw_local_irq_restore(flags);
459 if (!regs) {
460 oops_exit();
461 return;
462 }
463 if (in_interrupt())
464 panic("Fatal exception in interrupt");
465 if (panic_on_oops)
466 panic("Fatal exception");
467 oops_exit();
468 do_exit(signr);
469}
470
471int __kprobes __die(const char *str, struct pt_regs *regs, long err)
472{
473 printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff, ++die_counter);
474#ifdef CONFIG_PREEMPT
475 printk("PREEMPT ");
476#endif
477#ifdef CONFIG_SMP
478 printk("SMP ");
479#endif
480#ifdef CONFIG_DEBUG_PAGEALLOC
481 printk("DEBUG_PAGEALLOC");
482#endif
483 printk("\n");
484 if (notify_die(DIE_OOPS, str, regs, err,
485 current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
486 return 1;
487
488 show_registers(regs);
489 add_taint(TAINT_DIE);
490 /* Executive summary in case the oops scrolled away */
491 printk(KERN_ALERT "RIP ");
492 printk_address(regs->ip, 1);
493 printk(" RSP <%016lx>\n", regs->sp);
494 if (kexec_should_crash(current))
495 crash_kexec(regs);
496 return 0;
497}
498
499void die(const char *str, struct pt_regs *regs, long err)
500{
501 unsigned long flags = oops_begin();
502
503 if (!user_mode(regs))
504 report_bug(regs->ip, regs);
505
506 if (__die(str, regs, err))
507 regs = NULL;
508 oops_end(flags, regs, SIGSEGV);
509}
510
511notrace __kprobes void
512die_nmi(char *str, struct pt_regs *regs, int do_panic)
513{
514 unsigned long flags;
515
516 if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
517 return;
518
519 flags = oops_begin();
520 /*
521 * We are in trouble anyway, lets at least try
522 * to get a message out.
523 */
524 printk(KERN_EMERG "%s", str);
525 printk(" on CPU%d, ip %08lx, registers:\n",
526 smp_processor_id(), regs->ip);
527 show_registers(regs);
528 if (kexec_should_crash(current))
529 crash_kexec(regs);
530 if (do_panic || panic_on_oops)
531 panic("Non maskable interrupt");
532 oops_end(flags, NULL, SIGBUS);
533 nmi_exit();
534 local_irq_enable();
535 do_exit(SIGBUS);
536}
537
538static int __init oops_setup(char *s)
539{
540 if (!s)
541 return -EINVAL;
542 if (!strcmp(s, "panic"))
543 panic_on_oops = 1;
544 return 0;
545}
546early_param("oops", oops_setup);
547
548static int __init kstack_setup(char *s)
549{
550 if (!s)
551 return -EINVAL;
552 kstack_depth_to_print = simple_strtoul(s, NULL, 0);
553 return 0;
554}
555early_param("kstack", kstack_setup);
556
557static int __init code_bytes_setup(char *s)
558{
559 code_bytes = simple_strtoul(s, NULL, 0);
560 if (code_bytes > 8192)
561 code_bytes = 8192;
562
563 return 1;
564}
565__setup("code_bytes=", code_bytes_setup);
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index 729157ee4c17..1cd61ddd90be 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -54,11 +54,7 @@
54 54
55#include <mach_traps.h> 55#include <mach_traps.h>
56 56
57int panic_on_unrecovered_nmi;
58int kstack_depth_to_print = 12;
59static unsigned int code_bytes = 64;
60static int ignore_nmis; 57static int ignore_nmis;
61static int die_counter;
62 58
63static inline void conditional_sti(struct pt_regs *regs) 59static inline void conditional_sti(struct pt_regs *regs)
64{ 60{
@@ -82,518 +78,6 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
82 dec_preempt_count(); 78 dec_preempt_count();
83} 79}
84 80
85void printk_address(unsigned long address, int reliable)
86{
87 printk(" [<%016lx>] %s%pS\n",
88 address, reliable ? "" : "? ", (void *) address);
89}
90
91static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
92 unsigned *usedp, char **idp)
93{
94 static char ids[][8] = {
95 [DEBUG_STACK - 1] = "#DB",
96 [NMI_STACK - 1] = "NMI",
97 [DOUBLEFAULT_STACK - 1] = "#DF",
98 [STACKFAULT_STACK - 1] = "#SS",
99 [MCE_STACK - 1] = "#MC",
100#if DEBUG_STKSZ > EXCEPTION_STKSZ
101 [N_EXCEPTION_STACKS ...
102 N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
103#endif
104 };
105 unsigned k;
106
107 /*
108 * Iterate over all exception stacks, and figure out whether
109 * 'stack' is in one of them:
110 */
111 for (k = 0; k < N_EXCEPTION_STACKS; k++) {
112 unsigned long end = per_cpu(orig_ist, cpu).ist[k];
113 /*
114 * Is 'stack' above this exception frame's end?
115 * If yes then skip to the next frame.
116 */
117 if (stack >= end)
118 continue;
119 /*
120 * Is 'stack' above this exception frame's start address?
121 * If yes then we found the right frame.
122 */
123 if (stack >= end - EXCEPTION_STKSZ) {
124 /*
125 * Make sure we only iterate through an exception
126 * stack once. If it comes up for the second time
127 * then there's something wrong going on - just
128 * break out and return NULL:
129 */
130 if (*usedp & (1U << k))
131 break;
132 *usedp |= 1U << k;
133 *idp = ids[k];
134 return (unsigned long *)end;
135 }
136 /*
137 * If this is a debug stack, and if it has a larger size than
138 * the usual exception stacks, then 'stack' might still
139 * be within the lower portion of the debug stack:
140 */
141#if DEBUG_STKSZ > EXCEPTION_STKSZ
142 if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
143 unsigned j = N_EXCEPTION_STACKS - 1;
144
145 /*
146 * Black magic. A large debug stack is composed of
147 * multiple exception stack entries, which we
148 * iterate through now. Dont look:
149 */
150 do {
151 ++j;
152 end -= EXCEPTION_STKSZ;
153 ids[j][4] = '1' + (j - N_EXCEPTION_STACKS);
154 } while (stack < end - EXCEPTION_STKSZ);
155 if (*usedp & (1U << j))
156 break;
157 *usedp |= 1U << j;
158 *idp = ids[j];
159 return (unsigned long *)end;
160 }
161#endif
162 }
163 return NULL;
164}
165
166/*
167 * x86-64 can have up to three kernel stacks:
168 * process stack
169 * interrupt stack
170 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
171 */
172
173static inline int valid_stack_ptr(struct thread_info *tinfo,
174 void *p, unsigned int size, void *end)
175{
176 void *t = tinfo;
177 if (end) {
178 if (p < end && p >= (end-THREAD_SIZE))
179 return 1;
180 else
181 return 0;
182 }
183 return p > t && p < t + THREAD_SIZE - size;
184}
185
186/* The form of the top of the frame on the stack */
187struct stack_frame {
188 struct stack_frame *next_frame;
189 unsigned long return_address;
190};
191
192static inline unsigned long
193print_context_stack(struct thread_info *tinfo,
194 unsigned long *stack, unsigned long bp,
195 const struct stacktrace_ops *ops, void *data,
196 unsigned long *end)
197{
198 struct stack_frame *frame = (struct stack_frame *)bp;
199
200 while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
201 unsigned long addr;
202
203 addr = *stack;
204 if (__kernel_text_address(addr)) {
205 if ((unsigned long) stack == bp + 8) {
206 ops->address(data, addr, 1);
207 frame = frame->next_frame;
208 bp = (unsigned long) frame;
209 } else {
210 ops->address(data, addr, bp == 0);
211 }
212 }
213 stack++;
214 }
215 return bp;
216}
217
218void dump_trace(struct task_struct *task, struct pt_regs *regs,
219 unsigned long *stack, unsigned long bp,
220 const struct stacktrace_ops *ops, void *data)
221{
222 const unsigned cpu = get_cpu();
223 unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr;
224 unsigned used = 0;
225 struct thread_info *tinfo;
226
227 if (!task)
228 task = current;
229
230 if (!stack) {
231 unsigned long dummy;
232 stack = &dummy;
233 if (task && task != current)
234 stack = (unsigned long *)task->thread.sp;
235 }
236
237#ifdef CONFIG_FRAME_POINTER
238 if (!bp) {
239 if (task == current) {
240 /* Grab bp right from our regs */
241 asm("movq %%rbp, %0" : "=r" (bp) : );
242 } else {
243 /* bp is the last reg pushed by switch_to */
244 bp = *(unsigned long *) task->thread.sp;
245 }
246 }
247#endif
248
249 /*
250 * Print function call entries in all stacks, starting at the
251 * current stack address. If the stacks consist of nested
252 * exceptions
253 */
254 tinfo = task_thread_info(task);
255 for (;;) {
256 char *id;
257 unsigned long *estack_end;
258 estack_end = in_exception_stack(cpu, (unsigned long)stack,
259 &used, &id);
260
261 if (estack_end) {
262 if (ops->stack(data, id) < 0)
263 break;
264
265 bp = print_context_stack(tinfo, stack, bp, ops,
266 data, estack_end);
267 ops->stack(data, "<EOE>");
268 /*
269 * We link to the next stack via the
270 * second-to-last pointer (index -2 to end) in the
271 * exception stack:
272 */
273 stack = (unsigned long *) estack_end[-2];
274 continue;
275 }
276 if (irqstack_end) {
277 unsigned long *irqstack;
278 irqstack = irqstack_end -
279 (IRQSTACKSIZE - 64) / sizeof(*irqstack);
280
281 if (stack >= irqstack && stack < irqstack_end) {
282 if (ops->stack(data, "IRQ") < 0)
283 break;
284 bp = print_context_stack(tinfo, stack, bp,
285 ops, data, irqstack_end);
286 /*
287 * We link to the next stack (which would be
288 * the process stack normally) the last
289 * pointer (index -1 to end) in the IRQ stack:
290 */
291 stack = (unsigned long *) (irqstack_end[-1]);
292 irqstack_end = NULL;
293 ops->stack(data, "EOI");
294 continue;
295 }
296 }
297 break;
298 }
299
300 /*
301 * This handles the process stack:
302 */
303 bp = print_context_stack(tinfo, stack, bp, ops, data, NULL);
304 put_cpu();
305}
306EXPORT_SYMBOL(dump_trace);
307
308static void
309print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
310{
311 print_symbol(msg, symbol);
312 printk("\n");
313}
314
315static void print_trace_warning(void *data, char *msg)
316{
317 printk("%s\n", msg);
318}
319
320static int print_trace_stack(void *data, char *name)
321{
322 printk(" <%s> ", name);
323 return 0;
324}
325
326static void print_trace_address(void *data, unsigned long addr, int reliable)
327{
328 touch_nmi_watchdog();
329 printk_address(addr, reliable);
330}
331
332static const struct stacktrace_ops print_trace_ops = {
333 .warning = print_trace_warning,
334 .warning_symbol = print_trace_warning_symbol,
335 .stack = print_trace_stack,
336 .address = print_trace_address,
337};
338
339static void
340show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
341 unsigned long *stack, unsigned long bp, char *log_lvl)
342{
343 printk("Call Trace:\n");
344 dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
345}
346
347void show_trace(struct task_struct *task, struct pt_regs *regs,
348 unsigned long *stack, unsigned long bp)
349{
350 show_trace_log_lvl(task, regs, stack, bp, "");
351}
352
353static void
354show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
355 unsigned long *sp, unsigned long bp, char *log_lvl)
356{
357 unsigned long *stack;
358 int i;
359 const int cpu = smp_processor_id();
360 unsigned long *irqstack_end =
361 (unsigned long *) (cpu_pda(cpu)->irqstackptr);
362 unsigned long *irqstack =
363 (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE);
364
365 /*
366 * debugging aid: "show_stack(NULL, NULL);" prints the
367 * back trace for this cpu.
368 */
369
370 if (sp == NULL) {
371 if (task)
372 sp = (unsigned long *)task->thread.sp;
373 else
374 sp = (unsigned long *)&sp;
375 }
376
377 stack = sp;
378 for (i = 0; i < kstack_depth_to_print; i++) {
379 if (stack >= irqstack && stack <= irqstack_end) {
380 if (stack == irqstack_end) {
381 stack = (unsigned long *) (irqstack_end[-1]);
382 printk(" <EOI> ");
383 }
384 } else {
385 if (((long) stack & (THREAD_SIZE-1)) == 0)
386 break;
387 }
388 if (i && ((i % 4) == 0))
389 printk("\n");
390 printk(" %016lx", *stack++);
391 touch_nmi_watchdog();
392 }
393 printk("\n");
394 show_trace_log_lvl(task, regs, sp, bp, log_lvl);
395}
396
397void show_stack(struct task_struct *task, unsigned long *sp)
398{
399 show_stack_log_lvl(task, NULL, sp, 0, "");
400}
401
402/*
403 * The architecture-independent dump_stack generator
404 */
405void dump_stack(void)
406{
407 unsigned long bp = 0;
408 unsigned long stack;
409
410#ifdef CONFIG_FRAME_POINTER
411 if (!bp)
412 asm("movq %%rbp, %0" : "=r" (bp) : );
413#endif
414
415 printk("Pid: %d, comm: %.20s %s %s %.*s\n",
416 current->pid, current->comm, print_tainted(),
417 init_utsname()->release,
418 (int)strcspn(init_utsname()->version, " "),
419 init_utsname()->version);
420 show_trace(NULL, NULL, &stack, bp);
421}
422EXPORT_SYMBOL(dump_stack);
423
424void show_registers(struct pt_regs *regs)
425{
426 int i;
427 unsigned long sp;
428 const int cpu = smp_processor_id();
429 struct task_struct *cur = cpu_pda(cpu)->pcurrent;
430
431 sp = regs->sp;
432 printk("CPU %d ", cpu);
433 __show_regs(regs, 1);
434 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
435 cur->comm, cur->pid, task_thread_info(cur), cur);
436
437 /*
438 * When in-kernel, we also print out the stack and code at the
439 * time of the fault..
440 */
441 if (!user_mode(regs)) {
442 unsigned int code_prologue = code_bytes * 43 / 64;
443 unsigned int code_len = code_bytes;
444 unsigned char c;
445 u8 *ip;
446
447 printk("Stack: ");
448 show_stack_log_lvl(NULL, regs, (unsigned long *)sp,
449 regs->bp, "");
450
451 printk(KERN_EMERG "Code: ");
452
453 ip = (u8 *)regs->ip - code_prologue;
454 if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
455 /* try starting at RIP */
456 ip = (u8 *)regs->ip;
457 code_len = code_len - code_prologue + 1;
458 }
459 for (i = 0; i < code_len; i++, ip++) {
460 if (ip < (u8 *)PAGE_OFFSET ||
461 probe_kernel_address(ip, c)) {
462 printk(" Bad RIP value.");
463 break;
464 }
465 if (ip == (u8 *)regs->ip)
466 printk("<%02x> ", c);
467 else
468 printk("%02x ", c);
469 }
470 }
471 printk("\n");
472}
473
474int is_valid_bugaddr(unsigned long ip)
475{
476 unsigned short ud2;
477
478 if (__copy_from_user(&ud2, (const void __user *) ip, sizeof(ud2)))
479 return 0;
480
481 return ud2 == 0x0b0f;
482}
483
484static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
485static int die_owner = -1;
486static unsigned int die_nest_count;
487
488unsigned __kprobes long oops_begin(void)
489{
490 int cpu;
491 unsigned long flags;
492
493 oops_enter();
494
495 /* racy, but better than risking deadlock. */
496 raw_local_irq_save(flags);
497 cpu = smp_processor_id();
498 if (!__raw_spin_trylock(&die_lock)) {
499 if (cpu == die_owner)
500 /* nested oops. should stop eventually */;
501 else
502 __raw_spin_lock(&die_lock);
503 }
504 die_nest_count++;
505 die_owner = cpu;
506 console_verbose();
507 bust_spinlocks(1);
508 return flags;
509}
510
511void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
512{
513 die_owner = -1;
514 bust_spinlocks(0);
515 die_nest_count--;
516 if (!die_nest_count)
517 /* Nest count reaches zero, release the lock. */
518 __raw_spin_unlock(&die_lock);
519 raw_local_irq_restore(flags);
520 if (!regs) {
521 oops_exit();
522 return;
523 }
524 if (panic_on_oops)
525 panic("Fatal exception");
526 oops_exit();
527 do_exit(signr);
528}
529
530int __kprobes __die(const char *str, struct pt_regs *regs, long err)
531{
532 printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff, ++die_counter);
533#ifdef CONFIG_PREEMPT
534 printk("PREEMPT ");
535#endif
536#ifdef CONFIG_SMP
537 printk("SMP ");
538#endif
539#ifdef CONFIG_DEBUG_PAGEALLOC
540 printk("DEBUG_PAGEALLOC");
541#endif
542 printk("\n");
543 if (notify_die(DIE_OOPS, str, regs, err,
544 current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
545 return 1;
546
547 show_registers(regs);
548 add_taint(TAINT_DIE);
549 /* Executive summary in case the oops scrolled away */
550 printk(KERN_ALERT "RIP ");
551 printk_address(regs->ip, 1);
552 printk(" RSP <%016lx>\n", regs->sp);
553 if (kexec_should_crash(current))
554 crash_kexec(regs);
555 return 0;
556}
557
558void die(const char *str, struct pt_regs *regs, long err)
559{
560 unsigned long flags = oops_begin();
561
562 if (!user_mode(regs))
563 report_bug(regs->ip, regs);
564
565 if (__die(str, regs, err))
566 regs = NULL;
567 oops_end(flags, regs, SIGSEGV);
568}
569
570notrace __kprobes void
571die_nmi(char *str, struct pt_regs *regs, int do_panic)
572{
573 unsigned long flags;
574
575 if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
576 return;
577
578 flags = oops_begin();
579 /*
580 * We are in trouble anyway, lets at least try
581 * to get a message out.
582 */
583 printk(KERN_EMERG "%s", str);
584 printk(" on CPU%d, ip %08lx, registers:\n",
585 smp_processor_id(), regs->ip);
586 show_registers(regs);
587 if (kexec_should_crash(current))
588 crash_kexec(regs);
589 if (do_panic || panic_on_oops)
590 panic("Non maskable interrupt");
591 oops_end(flags, NULL, SIGBUS);
592 nmi_exit();
593 local_irq_enable();
594 do_exit(SIGBUS);
595}
596
597static void __kprobes 81static void __kprobes
598do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, 82do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
599 long error_code, siginfo_t *info) 83 long error_code, siginfo_t *info)
@@ -1178,32 +662,3 @@ void __init trap_init(void)
1178 */ 662 */
1179 cpu_init(); 663 cpu_init();
1180} 664}
1181
1182static int __init oops_setup(char *s)
1183{
1184 if (!s)
1185 return -EINVAL;
1186 if (!strcmp(s, "panic"))
1187 panic_on_oops = 1;
1188 return 0;
1189}
1190early_param("oops", oops_setup);
1191
1192static int __init kstack_setup(char *s)
1193{
1194 if (!s)
1195 return -EINVAL;
1196 kstack_depth_to_print = simple_strtoul(s, NULL, 0);
1197 return 0;
1198}
1199early_param("kstack", kstack_setup);
1200
1201static int __init code_bytes_setup(char *s)
1202{
1203 code_bytes = simple_strtoul(s, NULL, 0);
1204 if (code_bytes > 8192)
1205 code_bytes = 8192;
1206
1207 return 1;
1208}
1209__setup("code_bytes=", code_bytes_setup);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-11 12:09:49 -0500