[deliverable/linux.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)
{
	printk(" [<%p>] %s%pS\n", (void *) address,
			reliable ? "" : "? ", (void *) address);
}

static inline int valid_stack_ptr(struct thread_info *tinfo,
			void *p, unsigned int size, void *end)
{
	void *t = tinfo;
	if (end) {
		if (p < end && p >= (end-THREAD_SIZE))
			return 1;
		else
			return 0;
	}
	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,
		unsigned long *end)
{
	struct stack_frame *frame = (struct stack_frame *)bp;

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

		addr = *stack;
		if (__kernel_text_address(addr)) {
			if ((unsigned long) stack == bp + sizeof(long)) {
				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, NULL);
		/*
		 * 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	{
16182790 AH	26	printk(" [<%p>] %s%pS\n", (void *) address,
16182790 AH	27	reliable ? "" : "? ", (void *) address);
2bc5f927 AH	28	}
	29
	30	static inline int valid_stack_ptr(struct thread_info *tinfo,
3a18512d	31	void p, unsigned int size, void end)
2bc5f927 AH	32	{
2bc5f927 AH	33	void *t = tinfo;
3a18512d AH	34	if (end) {
	35	if (p < end && p >= (end-THREAD_SIZE))
	36	return 1;
	37	else
	38	return 0;
	39	}
	40	return p > t && p < t + THREAD_SIZE - size;
2bc5f927 AH	41	}
	42
	43	/* The form of the top of the frame on the stack */
	44	struct stack_frame {
	45	struct stack_frame *next_frame;
	46	unsigned long return_address;
	47	};
	48
	49	static inline unsigned long
	50	print_context_stack(struct thread_info *tinfo,
	51	unsigned long *stack, unsigned long bp,
3a18512d AH	52	const struct stacktrace_ops ops, void data,
3a18512d AH	53	unsigned long *end)
2bc5f927 AH	54	{
	55	struct stack_frame frame = (struct stack_frame )bp;
	56
3a18512d	57	while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
2bc5f927 AH	58	unsigned long addr;
	59
	60	addr = *stack;
	61	if (__kernel_text_address(addr)) {
3a18512d	62	if ((unsigned long) stack == bp + sizeof(long)) {
2bc5f927 AH	63	ops->address(data, addr, 1);
	64	frame = frame->next_frame;
	65	bp = (unsigned long) frame;
	66	} else {
	67	ops->address(data, addr, bp == 0);
	68	}
	69	}
	70	stack++;
	71	}
	72	return bp;
	73	}
	74
	75	void dump_trace(struct task_struct task, struct pt_regs regs,
	76	unsigned long *stack, unsigned long bp,
	77	const struct stacktrace_ops ops, void data)
	78	{
	79	if (!task)
	80	task = current;
	81
	82	if (!stack) {
	83	unsigned long dummy;
	84	stack = &dummy;
	85	if (task != current)
	86	stack = (unsigned long *)task->thread.sp;
	87	}
	88
	89	#ifdef CONFIG_FRAME_POINTER
	90	if (!bp) {
	91	if (task == current) {
	92	/* Grab bp right from our regs */
	93	asm("movl %%ebp, %0" : "=r" (bp) :);
	94	} else {
	95	/* bp is the last reg pushed by switch_to */
	96	bp = (unsigned long ) task->thread.sp;
	97	}
	98	}
	99	#endif
	100
	101	for (;;) {
	102	struct thread_info *context;
	103
	104	context = (struct thread_info *)
	105	((unsigned long)stack & (~(THREAD_SIZE - 1)));
3a18512d	106	bp = print_context_stack(context, stack, bp, ops, data, NULL);
2bc5f927 AH	107	/*
	108	* Should be after the line below, but somewhere
	109	* in early boot context comes out corrupted and we
	110	* can't reference it:
	111	*/
	112	if (ops->stack(data, "IRQ") < 0)
	113	break;
	114	stack = (unsigned long *)context->previous_esp;
	115	if (!stack)
	116	break;
	117	touch_nmi_watchdog();
	118	}
	119	}
	120	EXPORT_SYMBOL(dump_trace);
	121
	122	static void
	123	print_trace_warning_symbol(void data, char msg, unsigned long symbol)
	124	{
	125	printk(data);
	126	print_symbol(msg, symbol);
	127	printk("\n");
	128	}
	129
	130	static void print_trace_warning(void data, char msg)
	131	{
	132	printk("%s%s\n", (char *)data, msg);
	133	}
	134
	135	static int print_trace_stack(void data, char name)
	136	{
	137	return 0;
	138	}
	139
	140	/*
	141	* Print one address/symbol entries per line.
	142	*/
	143	static void print_trace_address(void *data, unsigned long addr, int reliable)
	144	{
	145	printk("%s [<%08lx>] ", (char *)data, addr);
	146	if (!reliable)
	147	printk("? ");
	148	print_symbol("%s\n", addr);
	149	touch_nmi_watchdog();
	150	}
	151
	152	static const struct stacktrace_ops print_trace_ops = {
	153	.warning = print_trace_warning,
	154	.warning_symbol = print_trace_warning_symbol,
	155	.stack = print_trace_stack,
	156	.address = print_trace_address,
	157	};
	158
	159	static void
	160	show_trace_log_lvl(struct task_struct task, struct pt_regs regs,
	161	unsigned long stack, unsigned long bp, char log_lvl)
	162	{
	163	dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
	164	printk("%s =======================\n", log_lvl);
	165	}
	166
	167	void show_trace(struct task_struct task, struct pt_regs regs,
	168	unsigned long *stack, unsigned long bp)
	169	{
	170	show_trace_log_lvl(task, regs, stack, bp, "");
171	}
172
173	static void
174	show_stack_log_lvl(struct task_struct task, struct pt_regs regs,
175	unsigned long sp, unsigned long bp, char log_lvl)
176	{
177	unsigned long *stack;
178	int i;
179
180	if (sp == NULL) {
181	if (task)
182	sp = (unsigned long *)task->thread.sp;
183	else
184	sp = (unsigned long *)&sp;
185	}
186
187	stack = sp;
188	for (i = 0; i < kstack_depth_to_print; i++) {
189	if (kstack_end(stack))
190	break;
191	if (i && ((i % 8) == 0))
192	printk("\n%s ", log_lvl);
193	printk("%08lx ", *stack++);
194	}
195	printk("\n%sCall Trace:\n", log_lvl);
196
197	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
198	}
199
200	void show_stack(struct task_struct task, unsigned long sp)
201	{
202	printk(" ");
203	show_stack_log_lvl(task, NULL, sp, 0, "");
204	}
205
206	/*
207	* The architecture-independent dump_stack generator
208	*/
209	void dump_stack(void)
210	{
211	unsigned long bp = 0;
212	unsigned long stack;
213
214	#ifdef CONFIG_FRAME_POINTER
215	if (!bp)
216	asm("movl %%ebp, %0" : "=r" (bp):);
217	#endif
218
219	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
220	current->pid, current->comm, print_tainted(),
221	init_utsname()->release,
222	(int)strcspn(init_utsname()->version, " "),
223	init_utsname()->version);
224
225	show_trace(current, NULL, &stack, bp);
226	}
227
228	EXPORT_SYMBOL(dump_stack);
229
230	void show_registers(struct pt_regs *regs)
231	{
232	int i;
233
234	print_modules();
235	__show_regs(regs, 0);
236
237	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
238	TASK_COMM_LEN, current->comm, task_pid_nr(current),
239	current_thread_info(), current, task_thread_info(current));
240	/*
241	* When in-kernel, we also print out the stack and code at the
242	* time of the fault..
243	*/
244	if (!user_mode_vm(regs)) {
245	unsigned int code_prologue = code_bytes * 43 / 64;
246	unsigned int code_len = code_bytes;
247	unsigned char c;
248	u8 *ip;
249
250	printk("\n" KERN_EMERG "Stack: ");
251	show_stack_log_lvl(NULL, regs, &regs->sp, 0, KERN_EMERG);
252
253	printk(KERN_EMERG "Code: ");
254
255	ip = (u8 *)regs->ip - code_prologue;
256	if (ip < (u8 *)PAGE_OFFSET \|\| probe_kernel_address(ip, c)) {
257	/* try starting at EIP */
258	ip = (u8 *)regs->ip;
259	code_len = code_len - code_prologue + 1;
260	}
261	for (i = 0; i < code_len; i++, ip++) {
262	if (ip < (u8 *)PAGE_OFFSET \|\|
263	probe_kernel_address(ip, c)) {
264	printk(" Bad EIP value.");
265	break;
266	}
267	if (ip == (u8 *)regs->ip)
268	printk("<%02x> ", c);
269	else
270	printk("%02x ", c);
271	}
272	}
273	printk("\n");
274	}
275
276	int is_valid_bugaddr(unsigned long ip)
277	{
278	unsigned short ud2;
279
280	if (ip < PAGE_OFFSET)
281	return 0;
282	if (probe_kernel_address((unsigned short *)ip, ud2))
283	return 0;
284
285	return ud2 == 0x0b0f;
286	}
287
288	static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
289	static int die_owner = -1;
290	static unsigned int die_nest_count;
291
292	unsigned __kprobes long oops_begin(void)
293	{
294	unsigned long flags;
295
296	oops_enter();
297
298	if (die_owner != raw_smp_processor_id()) {
299	console_verbose();
300	raw_local_irq_save(flags);
301	__raw_spin_lock(&die_lock);
302	die_owner = smp_processor_id();
303	die_nest_count = 0;
304	bust_spinlocks(1);
305	} else {
306	raw_local_irq_save(flags);
307	}
308	die_nest_count++;
309	return flags;
310	}
311
312	void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
313	{
314	bust_spinlocks(0);
315	die_owner = -1;
316	add_taint(TAINT_DIE);
317	__raw_spin_unlock(&die_lock);
318	raw_local_irq_restore(flags);
319
320	if (!regs)
321	return;
322
323	if (kexec_should_crash(current))
324	crash_kexec(regs);
325
326	if (in_interrupt())
327	panic("Fatal exception in interrupt");
328
329	if (panic_on_oops)
330	panic("Fatal exception");
331
332	oops_exit();
333	do_exit(signr);
334	}
335
336	int __kprobes __die(const char str, struct pt_regs regs, long err)
337	{
338	unsigned short ss;
339	unsigned long sp;
340
341	printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
342	#ifdef CONFIG_PREEMPT
343	printk("PREEMPT ");
344	#endif
345	#ifdef CONFIG_SMP
346	printk("SMP ");
347	#endif
348	#ifdef CONFIG_DEBUG_PAGEALLOC
349	printk("DEBUG_PAGEALLOC");
350	#endif
351	printk("\n");
352	if (notify_die(DIE_OOPS, str, regs, err,
353	current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
354	return 1;
355
356	show_registers(regs);
357	/* Executive summary in case the oops scrolled away */
358	sp = (unsigned long) (&regs->sp);
359	savesegment(ss, ss);
360	if (user_mode(regs)) {
361	sp = regs->sp;
362	ss = regs->ss & 0xffff;
363	}
364	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
365	print_symbol("%s", regs->ip);
366	printk(" SS:ESP %04x:%08lx\n", ss, sp);
367	return 0;
368	}
369
370	/*
371	* This is gone through when something in the kernel has done something bad
372	* and is about to be terminated:
373	*/
374	void die(const char str, struct pt_regs regs, long err)
375	{
376	unsigned long flags = oops_begin();
377
378	if (die_nest_count < 3) {
379	report_bug(regs->ip, regs);
380
381	if (__die(str, regs, err))
382	regs = NULL;
383	} else {
384	printk(KERN_EMERG "Recursive die() failure, output suppressed\n");
385	}
386
387	oops_end(flags, regs, SIGSEGV);
388	}
389
dd6e4eba AH	390	static DEFINE_SPINLOCK(nmi_print_lock);
	391
	392	void notrace __kprobes
	393	die_nmi(char str, struct pt_regs regs, int do_panic)
	394	{
	395	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
	396	return;
	397
	398	spin_lock(&nmi_print_lock);
	399	/*
	400	* We are in trouble anyway, lets at least try
	401	* to get a message out:
	402	*/
	403	bust_spinlocks(1);
	404	printk(KERN_EMERG "%s", str);
	405	printk(" on CPU%d, ip %08lx, registers:\n",
	406	smp_processor_id(), regs->ip);
	407	show_registers(regs);
	408	if (do_panic)
	409	panic("Non maskable interrupt");
	410	console_silent();
	411	spin_unlock(&nmi_print_lock);
	412	bust_spinlocks(0);
	413
	414	/*
	415	* If we are in kernel we are probably nested up pretty bad
	416	* and might aswell get out now while we still can:
	417	*/
	418	if (!user_mode_vm(regs)) {
	419	current->thread.trap_no = 2;
	420	crash_kexec(regs);
	421	}
	422
	423	do_exit(SIGSEGV);
	424	}
	425
2bc5f927 AH	426	static int __init kstack_setup(char *s)
	427	{
	428	kstack_depth_to_print = simple_strtoul(s, NULL, 0);
	429
	430	return 1;
	431	}
	432	__setup("kstack=", kstack_setup);
	433
	434	static int __init code_bytes_setup(char *s)
	435	{
	436	code_bytes = simple_strtoul(s, NULL, 0);
	437	if (code_bytes > 8192)
	438	code_bytes = 8192;
	439
	440	return 1;
	441	}
	442	__setup("code_bytes=", code_bytes_setup);