[deliverable/linux.git] / arch / x86 / kernel / dumpstack.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/ftrace.h>
#include <linux/kexec.h>
#include <linux/bug.h>
#include <linux/nmi.h>
#include <linux/sysfs.h>

#include <asm/stacktrace.h>


int panic_on_unrecovered_nmi;
int panic_on_io_nmi;
unsigned int code_bytes = 64;
int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
static int die_counter;

void printk_address(unsigned long address, int reliable)
{
	pr_cont(" [<%p>] %s%pB\n",
		(void *)address, reliable ? "" : "? ", (void *)address);
}

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static void
print_ftrace_graph_addr(unsigned long addr, void *data,
			const struct stacktrace_ops *ops,
			struct thread_info *tinfo, int *graph)
{
	struct task_struct *task;
	unsigned long ret_addr;
	int index;

	if (addr != (unsigned long)return_to_handler)
		return;

	task = tinfo->task;
	index = task->curr_ret_stack;

	if (!task->ret_stack || index < *graph)
		return;

	index -= *graph;
	ret_addr = task->ret_stack[index].ret;

	ops->address(data, ret_addr, 1);

	(*graph)++;
}
#else
static inline void
print_ftrace_graph_addr(unsigned long addr, void *data,
			const struct stacktrace_ops *ops,
			struct thread_info *tinfo, int *graph)
{ }
#endif

/*
 * x86-64 can have up to three kernel stacks:
 * process stack
 * interrupt stack
 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
 */

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;
}

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, int *graph)
{
	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, 0);
			}
			print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
		}
		stack++;
	}
	return bp;
}
EXPORT_SYMBOL_GPL(print_context_stack);

unsigned long
print_context_stack_bp(struct thread_info *tinfo,
		       unsigned long *stack, unsigned long bp,
		       const struct stacktrace_ops *ops, void *data,
		       unsigned long *end, int *graph)
{
	struct stack_frame *frame = (struct stack_frame *)bp;
	unsigned long *ret_addr = &frame->return_address;

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

		if (!__kernel_text_address(addr))
			break;

		ops->address(data, addr, 1);
		frame = frame->next_frame;
		ret_addr = &frame->return_address;
		print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
	}

	return (unsigned long)frame;
}
EXPORT_SYMBOL_GPL(print_context_stack_bp);

static int print_trace_stack(void *data, char *name)
{
	printk("%s <%s> ", (char *)data, name);
	return 0;
}

/*
 * Print one address/symbol entries per line.
 */
static void print_trace_address(void *data, unsigned long addr, int reliable)
{
	touch_nmi_watchdog();
	printk(data);
	printk_address(addr, reliable);
}

static const struct stacktrace_ops print_trace_ops = {
	.stack			= print_trace_stack,
	.address		= print_trace_address,
	.walk_stack		= print_context_stack,
};

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

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

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

	bp = stack_frame(current, NULL);
	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(NULL, NULL, &stack, bp);
}
EXPORT_SYMBOL(dump_stack);

static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
static int die_owner = -1;
static unsigned int die_nest_count;

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

	oops_enter();

	/* racy, but better than risking deadlock. */
	raw_local_irq_save(flags);
	cpu = smp_processor_id();
	if (!arch_spin_trylock(&die_lock)) {
		if (cpu == die_owner)
			/* nested oops. should stop eventually */;
		else
			arch_spin_lock(&die_lock);
	}
	die_nest_count++;
	die_owner = cpu;
	console_verbose();
	bust_spinlocks(1);
	return flags;
}
EXPORT_SYMBOL_GPL(oops_begin);

void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
{
	if (regs && kexec_should_crash(current))
		crash_kexec(regs);

	bust_spinlocks(0);
	die_owner = -1;
	add_taint(TAINT_DIE);
	die_nest_count--;
	if (!die_nest_count)
		/* Nest count reaches zero, release the lock. */
		arch_spin_unlock(&die_lock);
	raw_local_irq_restore(flags);
	oops_exit();

	if (!signr)
		return;
	if (in_interrupt())
		panic("Fatal exception in interrupt");
	if (panic_on_oops)
		panic("Fatal exception");
	do_exit(signr);
}

int __kprobes __die(const char *str, struct pt_regs *regs, long err)
{
#ifdef CONFIG_X86_32
	unsigned short ss;
	unsigned long sp;
#endif
	printk(KERN_DEFAULT
	       "%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_nr, SIGSEGV) == NOTIFY_STOP)
		return 1;

	print_modules();
	show_regs(regs);
#ifdef CONFIG_X86_32
	if (user_mode_vm(regs)) {
		sp = regs->sp;
		ss = regs->ss & 0xffff;
	} else {
		sp = kernel_stack_pointer(regs);
		savesegment(ss, ss);
	}
	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
	print_symbol("%s", regs->ip);
	printk(" SS:ESP %04x:%08lx\n", ss, sp);
#else
	/* Executive summary in case the oops scrolled away */
	printk(KERN_ALERT "RIP ");
	printk_address(regs->ip, 1);
	printk(" RSP <%016lx>\n", regs->sp);
#endif
	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();
	int sig = SIGSEGV;

	if (!user_mode_vm(regs))
		report_bug(regs->ip, regs);

	if (__die(str, regs, err))
		sig = 0;
	oops_end(flags, regs, sig);
}

static int __init kstack_setup(char *s)
{
	ssize_t ret;
	unsigned long val;

	if (!s)
		return -EINVAL;

	ret = kstrtoul(s, 0, &val);
	if (ret)
		return ret;
	kstack_depth_to_print = val;
	return 0;
}
early_param("kstack", kstack_setup);

static int __init code_bytes_setup(char *s)
{
	ssize_t ret;
	unsigned long val;

	if (!s)
		return -EINVAL;

	ret = kstrtoul(s, 0, &val);
	if (ret)
		return ret;

	code_bytes = val;
	if (code_bytes > 8192)
		code_bytes = 8192;

	return 1;
}
__setup("code_bytes=", code_bytes_setup);
Commit	Line	Data
878719e8 NH	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>
712406a6	13	#include <linux/ftrace.h>
878719e8 NH	14	#include <linux/kexec.h>
	15	#include <linux/bug.h>
	16	#include <linux/nmi.h>
	17	#include <linux/sysfs.h>
	18
	19	#include <asm/stacktrace.h>
	20
878719e8 NH	21
878719e8 NH	22	int panic_on_unrecovered_nmi;
5211a242	23	int panic_on_io_nmi;
878719e8 NH	24	unsigned int code_bytes = 64;
	25	int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
	26	static int die_counter;
	27
	28	void printk_address(unsigned long address, int reliable)
	29	{
c767a54b JP	30	pr_cont(" [<%p>] %s%pB\n",
c767a54b JP	31	(void )address, reliable ? "" : "? ", (void )address);
878719e8 NH	32	}
878719e8 NH	33
7ee991fb SR	34	#ifdef CONFIG_FUNCTION_GRAPH_TRACER
	35	static void
	36	print_ftrace_graph_addr(unsigned long addr, void *data,
	37	const struct stacktrace_ops *ops,
	38	struct thread_info tinfo, int graph)
	39	{
65c0ff40	40	struct task_struct *task;
7ee991fb	41	unsigned long ret_addr;
65c0ff40	42	int index;
7ee991fb SR	43
	44	if (addr != (unsigned long)return_to_handler)
	45	return;
	46
65c0ff40 HD	47	task = tinfo->task;
	48	index = task->curr_ret_stack;
	49
7ee991fb SR	50	if (!task->ret_stack \|\| index < *graph)
	51	return;
	52
	53	index -= *graph;
	54	ret_addr = task->ret_stack[index].ret;
	55
	56	ops->address(data, ret_addr, 1);
	57
	58	(*graph)++;
	59	}
	60	#else
	61	static inline void
	62	print_ftrace_graph_addr(unsigned long addr, void *data,
	63	const struct stacktrace_ops *ops,
	64	struct thread_info tinfo, int graph)
	65	{ }
	66	#endif
	67
878719e8 NH	68	/*
	69	* x86-64 can have up to three kernel stacks:
	70	* process stack
	71	* interrupt stack
	72	* severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
	73	*/
	74
	75	static inline int valid_stack_ptr(struct thread_info *tinfo,
	76	void p, unsigned int size, void end)
	77	{
	78	void *t = tinfo;
	79	if (end) {
	80	if (p < end && p >= (end-THREAD_SIZE))
	81	return 1;
	82	else
	83	return 0;
	84	}
	85	return p > t && p < t + THREAD_SIZE - size;
	86	}
	87
	88	unsigned long
	89	print_context_stack(struct thread_info *tinfo,
	90	unsigned long *stack, unsigned long bp,
	91	const struct stacktrace_ops ops, void data,
7ee991fb	92	unsigned long end, int graph)
878719e8 NH	93	{
	94	struct stack_frame frame = (struct stack_frame )bp;
	95
	96	while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
	97	unsigned long addr;
	98
	99	addr = *stack;
	100	if (__kernel_text_address(addr)) {
	101	if ((unsigned long) stack == bp + sizeof(long)) {
	102	ops->address(data, addr, 1);
	103	frame = frame->next_frame;
	104	bp = (unsigned long) frame;
	105	} else {
2c344e9d	106	ops->address(data, addr, 0);
878719e8	107	}
7ee991fb	108	print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
878719e8 NH	109	}
	110	stack++;
	111	}
	112	return bp;
	113	}
06d65bda FW	114	EXPORT_SYMBOL_GPL(print_context_stack);
	115
	116	unsigned long
	117	print_context_stack_bp(struct thread_info *tinfo,
	118	unsigned long *stack, unsigned long bp,
	119	const struct stacktrace_ops ops, void data,
	120	unsigned long end, int graph)
	121	{
	122	struct stack_frame frame = (struct stack_frame )bp;
	123	unsigned long *ret_addr = &frame->return_address;
	124
	125	while (valid_stack_ptr(tinfo, ret_addr, sizeof(*ret_addr), end)) {
	126	unsigned long addr = *ret_addr;
	127
c2c5d45d FW	128	if (!__kernel_text_address(addr))
	129	break;
	130
	131	ops->address(data, addr, 1);
	132	frame = frame->next_frame;
	133	ret_addr = &frame->return_address;
	134	print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
06d65bda	135	}
c2c5d45d	136
06d65bda FW	137	return (unsigned long)frame;
	138	}
	139	EXPORT_SYMBOL_GPL(print_context_stack_bp);
878719e8	140
878719e8 NH	141	static int print_trace_stack(void data, char name)
	142	{
	143	printk("%s <%s> ", (char *)data, name);
	144	return 0;
	145	}
	146
	147	/*
	148	* Print one address/symbol entries per line.
	149	*/
	150	static void print_trace_address(void *data, unsigned long addr, int reliable)
	151	{
	152	touch_nmi_watchdog();
	153	printk(data);
	154	printk_address(addr, reliable);
	155	}
	156
	157	static const struct stacktrace_ops print_trace_ops = {
06d65bda FW	158	.stack = print_trace_stack,
06d65bda FW	159	.address = print_trace_address,
61c1917f	160	.walk_stack = print_context_stack,
878719e8 NH	161	};
	162
	163	void
	164	show_trace_log_lvl(struct task_struct task, struct pt_regs regs,
e8e999cf	165	unsigned long stack, unsigned long bp, char log_lvl)
878719e8 NH	166	{
878719e8 NH	167	printk("%sCall Trace:\n", log_lvl);
e8e999cf	168	dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
878719e8 NH	169	}
	170
	171	void show_trace(struct task_struct task, struct pt_regs regs,
e8e999cf	172	unsigned long *stack, unsigned long bp)
878719e8	173	{
e8e999cf	174	show_trace_log_lvl(task, regs, stack, bp, "");
878719e8 NH	175	}
	176
	177	void show_stack(struct task_struct task, unsigned long sp)
	178	{
e8e999cf	179	show_stack_log_lvl(task, NULL, sp, 0, "");
878719e8 NH	180	}
	181
	182	/*
	183	* The architecture-independent dump_stack generator
	184	*/
	185	void dump_stack(void)
	186	{
e8e999cf	187	unsigned long bp;
878719e8 NH	188	unsigned long stack;
878719e8 NH	189
e8e999cf	190	bp = stack_frame(current, NULL);
878719e8 NH	191	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
	192	current->pid, current->comm, print_tainted(),
	193	init_utsname()->release,
	194	(int)strcspn(init_utsname()->version, " "),
	195	init_utsname()->version);
e8e999cf	196	show_trace(NULL, NULL, &stack, bp);
878719e8 NH	197	}
	198	EXPORT_SYMBOL(dump_stack);
	199
edc35bd7	200	static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
878719e8 NH	201	static int die_owner = -1;
	202	static unsigned int die_nest_count;
	203
	204	unsigned __kprobes long oops_begin(void)
	205	{
	206	int cpu;
	207	unsigned long flags;
	208
	209	oops_enter();
	210
	211	/* racy, but better than risking deadlock. */
	212	raw_local_irq_save(flags);
	213	cpu = smp_processor_id();
0199c4e6	214	if (!arch_spin_trylock(&die_lock)) {
878719e8 NH	215	if (cpu == die_owner)
	216	/* nested oops. should stop eventually */;
	217	else
0199c4e6	218	arch_spin_lock(&die_lock);
878719e8 NH	219	}
	220	die_nest_count++;
	221	die_owner = cpu;
	222	console_verbose();
	223	bust_spinlocks(1);
	224	return flags;
	225	}
81e88fdc	226	EXPORT_SYMBOL_GPL(oops_begin);
878719e8 NH	227
	228	void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
	229	{
	230	if (regs && kexec_should_crash(current))
	231	crash_kexec(regs);
	232
	233	bust_spinlocks(0);
	234	die_owner = -1;
	235	add_taint(TAINT_DIE);
	236	die_nest_count--;
	237	if (!die_nest_count)
	238	/* Nest count reaches zero, release the lock. */
0199c4e6	239	arch_spin_unlock(&die_lock);
878719e8 NH	240	raw_local_irq_restore(flags);
	241	oops_exit();
	242
	243	if (!signr)
	244	return;
	245	if (in_interrupt())
	246	panic("Fatal exception in interrupt");
	247	if (panic_on_oops)
	248	panic("Fatal exception");
	249	do_exit(signr);
	250	}
	251
	252	int __kprobes __die(const char str, struct pt_regs regs, long err)
	253	{
	254	#ifdef CONFIG_X86_32
	255	unsigned short ss;
	256	unsigned long sp;
	257	#endif
b0f4c4b3 PB	258	printk(KERN_DEFAULT
b0f4c4b3 PB	259	"%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
878719e8 NH	260	#ifdef CONFIG_PREEMPT
	261	printk("PREEMPT ");
	262	#endif
	263	#ifdef CONFIG_SMP
	264	printk("SMP ");
	265	#endif
	266	#ifdef CONFIG_DEBUG_PAGEALLOC
	267	printk("DEBUG_PAGEALLOC");
	268	#endif
	269	printk("\n");
878719e8	270	if (notify_die(DIE_OOPS, str, regs, err,
51e7dc70	271	current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP)
878719e8 NH	272	return 1;
878719e8 NH	273
0fa0e2f0	274	print_modules();
57da8b96	275	show_regs(regs);
878719e8	276	#ifdef CONFIG_X86_32
a343c75d	277	if (user_mode_vm(regs)) {
878719e8 NH	278	sp = regs->sp;
878719e8 NH	279	ss = regs->ss & 0xffff;
a343c75d PA	280	} else {
	281	sp = kernel_stack_pointer(regs);
	282	savesegment(ss, ss);
878719e8 NH	283	}
	284	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
	285	print_symbol("%s", regs->ip);
	286	printk(" SS:ESP %04x:%08lx\n", ss, sp);
	287	#else
	288	/* Executive summary in case the oops scrolled away */
	289	printk(KERN_ALERT "RIP ");
	290	printk_address(regs->ip, 1);
	291	printk(" RSP <%016lx>\n", regs->sp);
	292	#endif
	293	return 0;
	294	}
	295
	296	/*
	297	* This is gone through when something in the kernel has done something bad
	298	* and is about to be terminated:
	299	*/
	300	void die(const char str, struct pt_regs regs, long err)
	301	{
	302	unsigned long flags = oops_begin();
	303	int sig = SIGSEGV;
	304
	305	if (!user_mode_vm(regs))
	306	report_bug(regs->ip, regs);
	307
	308	if (__die(str, regs, err))
	309	sig = 0;
	310	oops_end(flags, regs, sig);
	311	}
	312
878719e8 NH	313	static int __init kstack_setup(char *s)
878719e8 NH	314	{
363f7ce3 SK	315	ssize_t ret;
	316	unsigned long val;
	317
878719e8 NH	318	if (!s)
878719e8 NH	319	return -EINVAL;
363f7ce3 SK	320
	321	ret = kstrtoul(s, 0, &val);
	322	if (ret)
	323	return ret;
	324	kstack_depth_to_print = val;
878719e8 NH	325	return 0;
	326	}
	327	early_param("kstack", kstack_setup);
	328
	329	static int __init code_bytes_setup(char *s)
	330	{
363f7ce3 SK	331	ssize_t ret;
	332	unsigned long val;
	333
	334	if (!s)
	335	return -EINVAL;
	336
	337	ret = kstrtoul(s, 0, &val);
	338	if (ret)
	339	return ret;
	340
	341	code_bytes = val;
878719e8 NH	342	if (code_bytes > 8192)
	343	code_bytes = 8192;
	344
	345	return 1;
	346	}
	347	__setup("code_bytes=", code_bytes_setup);