[linux-2.6-block.git] / arch / x86 / kernel / dumpstack_32.c

/*
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
 */
#include <linux/kallsyms.h>
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/utsname.h>
#include <linux/hardirq.h>
#include <linux/kdebug.h>
#include <linux/module.h>
#include <linux/ptrace.h>
#include <linux/kexec.h>
#include <linux/bug.h>
#include <linux/nmi.h>

#include <asm/stacktrace.h>

int panic_on_unrecovered_nmi;
int kstack_depth_to_print = 24;
static unsigned int code_bytes = 64;
static int die_counter;

void printk_address(unsigned long address, int reliable)
{
#ifdef CONFIG_KALLSYMS
	unsigned long offset = 0;
	unsigned long symsize;
	const char *symname;
	char *modname;
	char *delim = ":";
	char namebuf[KSYM_NAME_LEN];
	char reliab[4] = "";

	symname = kallsyms_lookup(address, &symsize, &offset,
					&modname, namebuf);
	if (!symname) {
		printk(" [<%08lx>]\n", address);
		return;
	}
	if (!reliable)
		strcpy(reliab, "? ");

	if (!modname)
		modname = delim = "";
	printk(" [<%08lx>] %s%s%s%s%s+0x%lx/0x%lx\n",
		address, reliab, delim, modname, delim, symname, offset, symsize);
#else
	printk(" [<%08lx>]\n", address);
#endif
}

static inline int valid_stack_ptr(struct thread_info *tinfo,
			void *p, unsigned int size)
{
	void *t = tinfo;
	return	p > t && p <= t + THREAD_SIZE - size;
}

/* The form of the top of the frame on the stack */
struct stack_frame {
	struct stack_frame *next_frame;
	unsigned long return_address;
};

static inline unsigned long
print_context_stack(struct thread_info *tinfo,
		unsigned long *stack, unsigned long bp,
		const struct stacktrace_ops *ops, void *data)
{
	struct stack_frame *frame = (struct stack_frame *)bp;

	while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
		unsigned long addr;

		addr = *stack;
		if (__kernel_text_address(addr)) {
			if ((unsigned long) stack == bp + 4) {
				ops->address(data, addr, 1);
				frame = frame->next_frame;
				bp = (unsigned long) frame;
			} else {
				ops->address(data, addr, bp == 0);
			}
		}
		stack++;
	}
	return bp;
}

void dump_trace(struct task_struct *task, struct pt_regs *regs,
		unsigned long *stack, unsigned long bp,
		const struct stacktrace_ops *ops, void *data)
{
	if (!task)
		task = current;

	if (!stack) {
		unsigned long dummy;
		stack = &dummy;
		if (task != current)
			stack = (unsigned long *)task->thread.sp;
	}

#ifdef CONFIG_FRAME_POINTER
	if (!bp) {
		if (task == current) {
			/* Grab bp right from our regs */
			asm("movl %%ebp, %0" : "=r" (bp) :);
		} else {
			/* bp is the last reg pushed by switch_to */
			bp = *(unsigned long *) task->thread.sp;
		}
	}
#endif

	for (;;) {
		struct thread_info *context;

		context = (struct thread_info *)
			((unsigned long)stack & (~(THREAD_SIZE - 1)));
		bp = print_context_stack(context, stack, bp, ops, data);
		/*
		 * Should be after the line below, but somewhere
		 * in early boot context comes out corrupted and we
		 * can't reference it:
		 */
		if (ops->stack(data, "IRQ") < 0)
			break;
		stack = (unsigned long *)context->previous_esp;
		if (!stack)
			break;
		touch_nmi_watchdog();
	}
}
EXPORT_SYMBOL(dump_trace);

static void
print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
{
	printk(data);
	print_symbol(msg, symbol);
	printk("\n");
}

static void print_trace_warning(void *data, char *msg)
{
	printk("%s%s\n", (char *)data, msg);
}

static int print_trace_stack(void *data, char *name)
{
	return 0;
}

/*
 * Print one address/symbol entries per line.
 */
static void print_trace_address(void *data, unsigned long addr, int reliable)
{
	printk("%s [<%08lx>] ", (char *)data, addr);
	if (!reliable)
		printk("? ");
	print_symbol("%s\n", addr);
	touch_nmi_watchdog();
}

static const struct stacktrace_ops print_trace_ops = {
	.warning = print_trace_warning,
	.warning_symbol = print_trace_warning_symbol,
	.stack = print_trace_stack,
	.address = print_trace_address,
};

static void
show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
		unsigned long *stack, unsigned long bp, char *log_lvl)
{
	dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
	printk("%s =======================\n", log_lvl);
}

void show_trace(struct task_struct *task, struct pt_regs *regs,
		unsigned long *stack, unsigned long bp)
{
	show_trace_log_lvl(task, regs, stack, bp, "");
}

static void
show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
		   unsigned long *sp, unsigned long bp, char *log_lvl)
{
	unsigned long *stack;
	int i;

	if (sp == NULL) {
		if (task)
			sp = (unsigned long *)task->thread.sp;
		else
			sp = (unsigned long *)&sp;
	}

	stack = sp;
	for (i = 0; i < kstack_depth_to_print; i++) {
		if (kstack_end(stack))
			break;
		if (i && ((i % 8) == 0))
			printk("\n%s       ", log_lvl);
		printk("%08lx ", *stack++);
	}
	printk("\n%sCall Trace:\n", log_lvl);

	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
}

void show_stack(struct task_struct *task, unsigned long *sp)
{
	printk("       ");
	show_stack_log_lvl(task, NULL, sp, 0, "");
}

/*
 * The architecture-independent dump_stack generator
 */
void dump_stack(void)
{
	unsigned long bp = 0;
	unsigned long stack;

#ifdef CONFIG_FRAME_POINTER
	if (!bp)
		asm("movl %%ebp, %0" : "=r" (bp):);
#endif

	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
		current->pid, current->comm, print_tainted(),
		init_utsname()->release,
		(int)strcspn(init_utsname()->version, " "),
		init_utsname()->version);

	show_trace(current, NULL, &stack, bp);
}

EXPORT_SYMBOL(dump_stack);

void show_registers(struct pt_regs *regs)
{
	int i;

	print_modules();
	__show_regs(regs, 0);

	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
		TASK_COMM_LEN, current->comm, task_pid_nr(current),
		current_thread_info(), current, task_thread_info(current));
	/*
	 * When in-kernel, we also print out the stack and code at the
	 * time of the fault..
	 */
	if (!user_mode_vm(regs)) {
		unsigned int code_prologue = code_bytes * 43 / 64;
		unsigned int code_len = code_bytes;
		unsigned char c;
		u8 *ip;

		printk("\n" KERN_EMERG "Stack: ");
		show_stack_log_lvl(NULL, regs, &regs->sp, 0, KERN_EMERG);

		printk(KERN_EMERG "Code: ");

		ip = (u8 *)regs->ip - code_prologue;
		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
			/* try starting at EIP */
			ip = (u8 *)regs->ip;
			code_len = code_len - code_prologue + 1;
		}
		for (i = 0; i < code_len; i++, ip++) {
			if (ip < (u8 *)PAGE_OFFSET ||
					probe_kernel_address(ip, c)) {
				printk(" Bad EIP value.");
				break;
			}
			if (ip == (u8 *)regs->ip)
				printk("<%02x> ", c);
			else
				printk("%02x ", c);
		}
	}
	printk("\n");
}

int is_valid_bugaddr(unsigned long ip)
{
	unsigned short ud2;

	if (ip < PAGE_OFFSET)
		return 0;
	if (probe_kernel_address((unsigned short *)ip, ud2))
		return 0;

	return ud2 == 0x0b0f;
}

static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
static int die_owner = -1;
static unsigned int die_nest_count;

unsigned __kprobes long oops_begin(void)
{
	unsigned long flags;

	oops_enter();

	if (die_owner != raw_smp_processor_id()) {
		console_verbose();
		raw_local_irq_save(flags);
		__raw_spin_lock(&die_lock);
		die_owner = smp_processor_id();
		die_nest_count = 0;
		bust_spinlocks(1);
	} else {
		raw_local_irq_save(flags);
	}
	die_nest_count++;
	return flags;
}

void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
{
	bust_spinlocks(0);
	die_owner = -1;
	add_taint(TAINT_DIE);
	__raw_spin_unlock(&die_lock);
	raw_local_irq_restore(flags);

	if (!regs)
		return;

	if (kexec_should_crash(current))
		crash_kexec(regs);

	if (in_interrupt())
		panic("Fatal exception in interrupt");

	if (panic_on_oops)
		panic("Fatal exception");

	oops_exit();
	do_exit(signr);
}

int __kprobes __die(const char *str, struct pt_regs *regs, long err)
{
	unsigned short ss;
	unsigned long sp;

	printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
#ifdef CONFIG_PREEMPT
	printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
	printk("SMP ");
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
	printk("DEBUG_PAGEALLOC");
#endif
	printk("\n");
	if (notify_die(DIE_OOPS, str, regs, err,
			current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
		return 1;

	show_registers(regs);
	/* Executive summary in case the oops scrolled away */
	sp = (unsigned long) (&regs->sp);
	savesegment(ss, ss);
	if (user_mode(regs)) {
		sp = regs->sp;
		ss = regs->ss & 0xffff;
	}
	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
	print_symbol("%s", regs->ip);
	printk(" SS:ESP %04x:%08lx\n", ss, sp);
	return 0;
}

/*
 * This is gone through when something in the kernel has done something bad
 * and is about to be terminated:
 */
void die(const char *str, struct pt_regs *regs, long err)
{
	unsigned long flags = oops_begin();

	if (die_nest_count < 3) {
		report_bug(regs->ip, regs);

		if (__die(str, regs, err))
			regs = NULL;
	} else {
		printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
	}

	oops_end(flags, regs, SIGSEGV);
}

static DEFINE_SPINLOCK(nmi_print_lock);

void notrace __kprobes
die_nmi(char *str, struct pt_regs *regs, int do_panic)
{
	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
		return;

	spin_lock(&nmi_print_lock);
	/*
	* We are in trouble anyway, lets at least try
	* to get a message out:
	*/
	bust_spinlocks(1);
	printk(KERN_EMERG "%s", str);
	printk(" on CPU%d, ip %08lx, registers:\n",
		smp_processor_id(), regs->ip);
	show_registers(regs);
	if (do_panic)
		panic("Non maskable interrupt");
	console_silent();
	spin_unlock(&nmi_print_lock);
	bust_spinlocks(0);

	/*
	 * If we are in kernel we are probably nested up pretty bad
	 * and might aswell get out now while we still can:
	 */
	if (!user_mode_vm(regs)) {
		current->thread.trap_no = 2;
		crash_kexec(regs);
	}

	do_exit(SIGSEGV);
}

static int __init kstack_setup(char *s)
{
	kstack_depth_to_print = simple_strtoul(s, NULL, 0);

	return 1;
}
__setup("kstack=", kstack_setup);

static int __init code_bytes_setup(char *s)
{
	code_bytes = simple_strtoul(s, NULL, 0);
	if (code_bytes > 8192)
		code_bytes = 8192;

	return 1;
}
__setup("code_bytes=", code_bytes_setup);
Commit	Line	Data
2bc5f927 AH	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
	19	int panic_on_unrecovered_nmi;
	20	int kstack_depth_to_print = 24;
	21	static unsigned int code_bytes = 64;
	22	static int die_counter;
	23
	24	void printk_address(unsigned long address, int reliable)
	25	{
	26	#ifdef CONFIG_KALLSYMS
	27	unsigned long offset = 0;
	28	unsigned long symsize;
	29	const char *symname;
	30	char *modname;
	31	char *delim = ":";
	32	char namebuf[KSYM_NAME_LEN];
	33	char reliab[4] = "";
	34
	35	symname = kallsyms_lookup(address, &symsize, &offset,
	36	&modname, namebuf);
	37	if (!symname) {
	38	printk(" [<%08lx>]\n", address);
	39	return;
	40	}
	41	if (!reliable)
	42	strcpy(reliab, "? ");
	43
	44	if (!modname)
	45	modname = delim = "";
	46	printk(" [<%08lx>] %s%s%s%s%s+0x%lx/0x%lx\n",
	47	address, reliab, delim, modname, delim, symname, offset, symsize);
	48	#else
	49	printk(" [<%08lx>]\n", address);
	50	#endif
	51	}
	52
	53	static inline int valid_stack_ptr(struct thread_info *tinfo,
	54	void *p, unsigned int size)
	55	{
	56	void *t = tinfo;
	57	return p > t && p <= t + THREAD_SIZE - size;
	58	}
	59
	60	/* The form of the top of the frame on the stack */
	61	struct stack_frame {
	62	struct stack_frame *next_frame;
	63	unsigned long return_address;
	64	};
65
66	static inline unsigned long
67	print_context_stack(struct thread_info *tinfo,
68	unsigned long *stack, unsigned long bp,
69	const struct stacktrace_ops ops, void data)
70	{
71	struct stack_frame frame = (struct stack_frame )bp;
72
73	while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
74	unsigned long addr;
75
76	addr = *stack;
77	if (__kernel_text_address(addr)) {
78	if ((unsigned long) stack == bp + 4) {
79	ops->address(data, addr, 1);
80	frame = frame->next_frame;
81	bp = (unsigned long) frame;
82	} else {
83	ops->address(data, addr, bp == 0);
84	}
85	}
86	stack++;
87	}
88	return bp;
89	}
90
91	void dump_trace(struct task_struct task, struct pt_regs regs,
92	unsigned long *stack, unsigned long bp,
93	const struct stacktrace_ops ops, void data)
94	{
95	if (!task)
96	task = current;
97
98	if (!stack) {
99	unsigned long dummy;
100	stack = &dummy;
101	if (task != current)
102	stack = (unsigned long *)task->thread.sp;
103	}
104
105	#ifdef CONFIG_FRAME_POINTER
106	if (!bp) {
107	if (task == current) {
108	/* Grab bp right from our regs */
109	asm("movl %%ebp, %0" : "=r" (bp) :);
110	} else {
111	/* bp is the last reg pushed by switch_to */
112	bp = (unsigned long ) task->thread.sp;
113	}
114	}
115	#endif
116
117	for (;;) {
118	struct thread_info *context;
119
120	context = (struct thread_info *)
121	((unsigned long)stack & (~(THREAD_SIZE - 1)));
122	bp = print_context_stack(context, stack, bp, ops, data);
123	/*
124	* Should be after the line below, but somewhere
125	* in early boot context comes out corrupted and we
126	* can't reference it:
127	*/
128	if (ops->stack(data, "IRQ") < 0)
129	break;
130	stack = (unsigned long *)context->previous_esp;
131	if (!stack)
132	break;
133	touch_nmi_watchdog();
134	}
135	}
136	EXPORT_SYMBOL(dump_trace);
137
138	static void
139	print_trace_warning_symbol(void data, char msg, unsigned long symbol)
140	{
141	printk(data);
142	print_symbol(msg, symbol);
143	printk("\n");
144	}
145
146	static void print_trace_warning(void data, char msg)
147	{
148	printk("%s%s\n", (char *)data, msg);
149	}
150
151	static int print_trace_stack(void data, char name)
152	{
153	return 0;
154	}
155
156	/*
157	* Print one address/symbol entries per line.
158	*/
159	static void print_trace_address(void *data, unsigned long addr, int reliable)
160	{
161	printk("%s [<%08lx>] ", (char *)data, addr);
162	if (!reliable)
163	printk("? ");
164	print_symbol("%s\n", addr);
165	touch_nmi_watchdog();
166	}
167
168	static const struct stacktrace_ops print_trace_ops = {
169	.warning = print_trace_warning,
170	.warning_symbol = print_trace_warning_symbol,
171	.stack = print_trace_stack,
172	.address = print_trace_address,
173	};
174
175	static void
176	show_trace_log_lvl(struct task_struct task, struct pt_regs regs,
177	unsigned long stack, unsigned long bp, char log_lvl)
178	{
179	dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
180	printk("%s =======================\n", log_lvl);
181	}
182
183	void show_trace(struct task_struct task, struct pt_regs regs,
184	unsigned long *stack, unsigned long bp)
185	{
186	show_trace_log_lvl(task, regs, stack, bp, "");
187	}
188
189	static void
190	show_stack_log_lvl(struct task_struct task, struct pt_regs regs,
191	unsigned long sp, unsigned long bp, char log_lvl)
192	{
193	unsigned long *stack;
194	int i;
195
196	if (sp == NULL) {
197	if (task)
198	sp = (unsigned long *)task->thread.sp;
199	else
200	sp = (unsigned long *)&sp;
201	}
202
203	stack = sp;
204	for (i = 0; i < kstack_depth_to_print; i++) {
205	if (kstack_end(stack))
206	break;
207	if (i && ((i % 8) == 0))
208	printk("\n%s ", log_lvl);
209	printk("%08lx ", *stack++);
210	}
211	printk("\n%sCall Trace:\n", log_lvl);
212
213	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
214	}
215
216	void show_stack(struct task_struct task, unsigned long sp)
217	{
218	printk(" ");
219	show_stack_log_lvl(task, NULL, sp, 0, "");
220	}
221
222	/*
223	* The architecture-independent dump_stack generator
224	*/
225	void dump_stack(void)
226	{
227	unsigned long bp = 0;
228	unsigned long stack;
229
230	#ifdef CONFIG_FRAME_POINTER
231	if (!bp)
232	asm("movl %%ebp, %0" : "=r" (bp):);
233	#endif
234
235	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
236	current->pid, current->comm, print_tainted(),
237	init_utsname()->release,
238	(int)strcspn(init_utsname()->version, " "),
239	init_utsname()->version);
240
241	show_trace(current, NULL, &stack, bp);
242	}
243
244	EXPORT_SYMBOL(dump_stack);
245
246	void show_registers(struct pt_regs *regs)
247	{
248	int i;
249
250	print_modules();
251	__show_regs(regs, 0);
252
253	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
254	TASK_COMM_LEN, current->comm, task_pid_nr(current),
255	current_thread_info(), current, task_thread_info(current));
256	/*
257	* When in-kernel, we also print out the stack and code at the
258	* time of the fault..
259	*/
260	if (!user_mode_vm(regs)) {
261	unsigned int code_prologue = code_bytes * 43 / 64;
262	unsigned int code_len = code_bytes;
263	unsigned char c;
264	u8 *ip;
265
266	printk("\n" KERN_EMERG "Stack: ");
267	show_stack_log_lvl(NULL, regs, &regs->sp, 0, KERN_EMERG);
268
269	printk(KERN_EMERG "Code: ");
270
271	ip = (u8 *)regs->ip - code_prologue;
272	if (ip < (u8 *)PAGE_OFFSET \|\| probe_kernel_address(ip, c)) {
273	/* try starting at EIP */
274	ip = (u8 *)regs->ip;
275	code_len = code_len - code_prologue + 1;
276	}
277	for (i = 0; i < code_len; i++, ip++) {
278	if (ip < (u8 *)PAGE_OFFSET \|\|
279	probe_kernel_address(ip, c)) {
280	printk(" Bad EIP value.");
281	break;
282	}
283	if (ip == (u8 *)regs->ip)
284	printk("<%02x> ", c);
285	else
286	printk("%02x ", c);
287	}
288	}
289	printk("\n");
290	}
291
292	int is_valid_bugaddr(unsigned long ip)
293	{
294	unsigned short ud2;
295
296	if (ip < PAGE_OFFSET)
297	return 0;
298	if (probe_kernel_address((unsigned short *)ip, ud2))
299	return 0;
300
301	return ud2 == 0x0b0f;
302	}
303
304	static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
305	static int die_owner = -1;
306	static unsigned int die_nest_count;
307
308	unsigned __kprobes long oops_begin(void)
309	{
310	unsigned long flags;
311
312	oops_enter();
313
314	if (die_owner != raw_smp_processor_id()) {
315	console_verbose();
316	raw_local_irq_save(flags);
317	__raw_spin_lock(&die_lock);
318	die_owner = smp_processor_id();
319	die_nest_count = 0;
320	bust_spinlocks(1);
321	} else {
322	raw_local_irq_save(flags);
323	}
324	die_nest_count++;
325	return flags;
326	}
327
328	void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
329	{
330	bust_spinlocks(0);
331	die_owner = -1;
332	add_taint(TAINT_DIE);
333	__raw_spin_unlock(&die_lock);
334	raw_local_irq_restore(flags);
335
336	if (!regs)
337	return;
338
339	if (kexec_should_crash(current))
340	crash_kexec(regs);
341
342	if (in_interrupt())
343	panic("Fatal exception in interrupt");
344
345	if (panic_on_oops)
346	panic("Fatal exception");
347
348	oops_exit();
349	do_exit(signr);
350	}
351
352	int __kprobes __die(const char str, struct pt_regs regs, long err)
353	{
354	unsigned short ss;
355	unsigned long sp;
356
357	printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
358	#ifdef CONFIG_PREEMPT
359	printk("PREEMPT ");
360	#endif
361	#ifdef CONFIG_SMP
362	printk("SMP ");
363	#endif
364	#ifdef CONFIG_DEBUG_PAGEALLOC
365	printk("DEBUG_PAGEALLOC");
366	#endif
367	printk("\n");
368	if (notify_die(DIE_OOPS, str, regs, err,
369	current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
370	return 1;
371
372	show_registers(regs);
373	/* Executive summary in case the oops scrolled away */
374	sp = (unsigned long) (&regs->sp);
375	savesegment(ss, ss);
376	if (user_mode(regs)) {
377	sp = regs->sp;
378	ss = regs->ss & 0xffff;
379	}
380	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
381	print_symbol("%s", regs->ip);
382	printk(" SS:ESP %04x:%08lx\n", ss, sp);
383	return 0;
384	}
385
386	/*
387	* This is gone through when something in the kernel has done something bad
388	* and is about to be terminated:
389	*/
390	void die(const char str, struct pt_regs regs, long err)
391	{
392	unsigned long flags = oops_begin();
393
394	if (die_nest_count < 3) {
395	report_bug(regs->ip, regs);
396
397	if (__die(str, regs, err))
398	regs = NULL;
399	} else {
400	printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
401	}
402
403	oops_end(flags, regs, SIGSEGV);
404	}
405
dd6e4eba AH	406	static DEFINE_SPINLOCK(nmi_print_lock);
	407
	408	void notrace __kprobes
	409	die_nmi(char str, struct pt_regs regs, int do_panic)
	410	{
	411	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
	412	return;
	413
	414	spin_lock(&nmi_print_lock);
	415	/*
	416	* We are in trouble anyway, lets at least try
	417	* to get a message out:
	418	*/
	419	bust_spinlocks(1);
	420	printk(KERN_EMERG "%s", str);
	421	printk(" on CPU%d, ip %08lx, registers:\n",
	422	smp_processor_id(), regs->ip);
	423	show_registers(regs);
	424	if (do_panic)
	425	panic("Non maskable interrupt");
	426	console_silent();
	427	spin_unlock(&nmi_print_lock);
	428	bust_spinlocks(0);
	429
	430	/*
	431	* If we are in kernel we are probably nested up pretty bad
	432	* and might aswell get out now while we still can:
	433	*/
	434	if (!user_mode_vm(regs)) {
	435	current->thread.trap_no = 2;
	436	crash_kexec(regs);
	437	}
	438
	439	do_exit(SIGSEGV);
	440	}
	441
2bc5f927 AH	442	static int __init kstack_setup(char *s)
	443	{
	444	kstack_depth_to_print = simple_strtoul(s, NULL, 0);
	445
	446	return 1;
	447	}
	448	__setup("kstack=", kstack_setup);
	449
	450	static int __init code_bytes_setup(char *s)
	451	{
	452	code_bytes = simple_strtoul(s, NULL, 0);
	453	if (code_bytes > 8192)
	454	code_bytes = 8192;
	455
	456	return 1;
	457	}
	458	__setup("code_bytes=", code_bytes_setup);