[mirror_ubuntu-artful-kernel.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/kexec.h>
#include <linux/bug.h>
#include <linux/nmi.h>
#include <linux/sysfs.h>

#include <asm/stacktrace.h>

#include "dumpstack.h"

int panic_on_unrecovered_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)
{
	printk(" [<%p>] %s%pS\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 = tinfo->task;
	unsigned long ret_addr;
	int index = task->curr_ret_stack;

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

	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, bp == 0);
			}
			print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
		}
		stack++;
	}
	return bp;
}


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)
{
	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 = {
	.warning = print_trace_warning,
	.warning_symbol = print_trace_warning_symbol,
	.stack = print_trace_stack,
	.address = print_trace_address,
};

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 = 0;
	unsigned long stack;

#ifdef CONFIG_FRAME_POINTER
	if (!bp)
		get_bp(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(NULL, NULL, &stack, bp);
}
EXPORT_SYMBOL(dump_stack);

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)
{
	int cpu;
	unsigned long flags;

	oops_enter();

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

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. */
		__raw_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_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");
	sysfs_printk_last_file();
	if (notify_die(DIE_OOPS, str, regs, err,
			current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
		return 1;

	show_registers(regs);
#ifdef CONFIG_X86_32
	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);
#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);
}

void notrace __kprobes
die_nmi(char *str, struct pt_regs *regs, int do_panic)
{
	unsigned long flags;

	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
		return;

	/*
	 * We are in trouble anyway, lets at least try
	 * to get a message out.
	 */
	flags = oops_begin();
	printk(KERN_EMERG "%s", str);
	printk(" on CPU%d, ip %08lx, registers:\n",
		smp_processor_id(), regs->ip);
	show_registers(regs);
	oops_end(flags, regs, 0);
	if (do_panic || panic_on_oops)
		panic("Non maskable interrupt");
	nmi_exit();
	local_irq_enable();
	do_exit(SIGBUS);
}

static int __init oops_setup(char *s)
{
	if (!s)
		return -EINVAL;
	if (!strcmp(s, "panic"))
		panic_on_oops = 1;
	return 0;
}
early_param("oops", oops_setup);

static int __init kstack_setup(char *s)
{
	if (!s)
		return -EINVAL;
	kstack_depth_to_print = simple_strtoul(s, NULL, 0);
	return 0;
}
early_param("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
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>
	13	#include <linux/kexec.h>
	14	#include <linux/bug.h>
	15	#include <linux/nmi.h>
	16	#include <linux/sysfs.h>
	17
	18	#include <asm/stacktrace.h>
	19
	20	#include "dumpstack.h"
	21
	22	int panic_on_unrecovered_nmi;
	23	unsigned int code_bytes = 64;
	24	int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE;
	25	static int die_counter;
	26
	27	void printk_address(unsigned long address, int reliable)
	28	{
	29	printk(" [<%p>] %s%pS\n", (void *) address,
	30	reliable ? "" : "? ", (void *) address);
	31	}
	32
7ee991fb SR	33	#ifdef CONFIG_FUNCTION_GRAPH_TRACER
	34	static void
	35	print_ftrace_graph_addr(unsigned long addr, void *data,
	36	const struct stacktrace_ops *ops,
	37	struct thread_info tinfo, int graph)
	38	{
	39	struct task_struct *task = tinfo->task;
	40	unsigned long ret_addr;
	41	int index = task->curr_ret_stack;
	42
	43	if (addr != (unsigned long)return_to_handler)
	44	return;
	45
	46	if (!task->ret_stack \|\| index < *graph)
	47	return;
	48
	49	index -= *graph;
	50	ret_addr = task->ret_stack[index].ret;
	51
	52	ops->address(data, ret_addr, 1);
	53
	54	(*graph)++;
	55	}
	56	#else
	57	static inline void
	58	print_ftrace_graph_addr(unsigned long addr, void *data,
	59	const struct stacktrace_ops *ops,
	60	struct thread_info tinfo, int graph)
	61	{ }
	62	#endif
	63
878719e8 NH	64	/*
	65	* x86-64 can have up to three kernel stacks:
	66	* process stack
	67	* interrupt stack
	68	* severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
	69	*/
	70
	71	static inline int valid_stack_ptr(struct thread_info *tinfo,
	72	void p, unsigned int size, void end)
	73	{
	74	void *t = tinfo;
	75	if (end) {
	76	if (p < end && p >= (end-THREAD_SIZE))
	77	return 1;
	78	else
	79	return 0;
	80	}
	81	return p > t && p < t + THREAD_SIZE - size;
	82	}
	83
	84	unsigned long
	85	print_context_stack(struct thread_info *tinfo,
	86	unsigned long *stack, unsigned long bp,
	87	const struct stacktrace_ops ops, void data,
7ee991fb	88	unsigned long end, int graph)
878719e8 NH	89	{
	90	struct stack_frame frame = (struct stack_frame )bp;
	91
	92	while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
	93	unsigned long addr;
	94
	95	addr = *stack;
	96	if (__kernel_text_address(addr)) {
	97	if ((unsigned long) stack == bp + sizeof(long)) {
	98	ops->address(data, addr, 1);
	99	frame = frame->next_frame;
	100	bp = (unsigned long) frame;
	101	} else {
	102	ops->address(data, addr, bp == 0);
	103	}
7ee991fb	104	print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
878719e8 NH	105	}
	106	stack++;
	107	}
	108	return bp;
	109	}
	110
	111
	112	static void
	113	print_trace_warning_symbol(void data, char msg, unsigned long symbol)
	114	{
	115	printk(data);
	116	print_symbol(msg, symbol);
	117	printk("\n");
	118	}
	119
	120	static void print_trace_warning(void data, char msg)
	121	{
	122	printk("%s%s\n", (char *)data, msg);
	123	}
	124
	125	static int print_trace_stack(void data, char name)
	126	{
	127	printk("%s <%s> ", (char *)data, name);
	128	return 0;
	129	}
	130
	131	/*
	132	* Print one address/symbol entries per line.
	133	*/
	134	static void print_trace_address(void *data, unsigned long addr, int reliable)
	135	{
	136	touch_nmi_watchdog();
	137	printk(data);
	138	printk_address(addr, reliable);
	139	}
	140
	141	static const struct stacktrace_ops print_trace_ops = {
	142	.warning = print_trace_warning,
	143	.warning_symbol = print_trace_warning_symbol,
	144	.stack = print_trace_stack,
	145	.address = print_trace_address,
	146	};
	147
	148	void
	149	show_trace_log_lvl(struct task_struct task, struct pt_regs regs,
	150	unsigned long stack, unsigned long bp, char log_lvl)
	151	{
	152	printk("%sCall Trace:\n", log_lvl);
	153	dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
	154	}
	155
	156	void show_trace(struct task_struct task, struct pt_regs regs,
	157	unsigned long *stack, unsigned long bp)
	158	{
	159	show_trace_log_lvl(task, regs, stack, bp, "");
	160	}
	161
	162	void show_stack(struct task_struct task, unsigned long sp)
	163	{
	164	show_stack_log_lvl(task, NULL, sp, 0, "");
	165	}
	166
	167	/*
	168	* The architecture-independent dump_stack generator
169	*/
170	void dump_stack(void)
171	{
172	unsigned long bp = 0;
173	unsigned long stack;
174
175	#ifdef CONFIG_FRAME_POINTER
176	if (!bp)
177	get_bp(bp);
178	#endif
179
180	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
181	current->pid, current->comm, print_tainted(),
182	init_utsname()->release,
183	(int)strcspn(init_utsname()->version, " "),
184	init_utsname()->version);
185	show_trace(NULL, NULL, &stack, bp);
186	}
187	EXPORT_SYMBOL(dump_stack);
188
189	static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
190	static int die_owner = -1;
191	static unsigned int die_nest_count;
192
193	unsigned __kprobes long oops_begin(void)
194	{
195	int cpu;
196	unsigned long flags;
197
198	oops_enter();
199
200	/* racy, but better than risking deadlock. */
201	raw_local_irq_save(flags);
202	cpu = smp_processor_id();
203	if (!__raw_spin_trylock(&die_lock)) {
204	if (cpu == die_owner)
205	/* nested oops. should stop eventually */;
206	else
207	__raw_spin_lock(&die_lock);
208	}
209	die_nest_count++;
210	die_owner = cpu;
211	console_verbose();
212	bust_spinlocks(1);
213	return flags;
214	}
215
216	void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
217	{
218	if (regs && kexec_should_crash(current))
219	crash_kexec(regs);
220
221	bust_spinlocks(0);
222	die_owner = -1;
223	add_taint(TAINT_DIE);
224	die_nest_count--;
225	if (!die_nest_count)
226	/* Nest count reaches zero, release the lock. */
227	__raw_spin_unlock(&die_lock);
228	raw_local_irq_restore(flags);
229	oops_exit();
230
231	if (!signr)
232	return;
233	if (in_interrupt())
234	panic("Fatal exception in interrupt");
235	if (panic_on_oops)
236	panic("Fatal exception");
237	do_exit(signr);
238	}
239
240	int __kprobes __die(const char str, struct pt_regs regs, long err)
241	{
242	#ifdef CONFIG_X86_32
243	unsigned short ss;
244	unsigned long sp;
245	#endif
246	printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter);
247	#ifdef CONFIG_PREEMPT
248	printk("PREEMPT ");
249	#endif
250	#ifdef CONFIG_SMP
251	printk("SMP ");
252	#endif
253	#ifdef CONFIG_DEBUG_PAGEALLOC
254	printk("DEBUG_PAGEALLOC");
255	#endif
256	printk("\n");
257	sysfs_printk_last_file();
258	if (notify_die(DIE_OOPS, str, regs, err,
259	current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
260	return 1;
261
262	show_registers(regs);
263	#ifdef CONFIG_X86_32
264	sp = (unsigned long) (&regs->sp);
265	savesegment(ss, ss);
266	if (user_mode(regs)) {
267	sp = regs->sp;
268	ss = regs->ss & 0xffff;
269	}
270	printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip);
271	print_symbol("%s", regs->ip);
272	printk(" SS:ESP %04x:%08lx\n", ss, sp);
273	#else
274	/* Executive summary in case the oops scrolled away */
275	printk(KERN_ALERT "RIP ");
276	printk_address(regs->ip, 1);
277	printk(" RSP <%016lx>\n", regs->sp);
278	#endif
279	return 0;
280	}
281
282	/*
283	* This is gone through when something in the kernel has done something bad
284	* and is about to be terminated:
285	*/
286	void die(const char str, struct pt_regs regs, long err)
287	{
288	unsigned long flags = oops_begin();
289	int sig = SIGSEGV;
290
291	if (!user_mode_vm(regs))
292	report_bug(regs->ip, regs);
293
294	if (__die(str, regs, err))
295	sig = 0;
296	oops_end(flags, regs, sig);
297	}
298
299	void notrace __kprobes
300	die_nmi(char str, struct pt_regs regs, int do_panic)
301	{
302	unsigned long flags;
303
304	if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
305	return;
306
307	/*
308	* We are in trouble anyway, lets at least try
309	* to get a message out.
310	*/
311	flags = oops_begin();
312	printk(KERN_EMERG "%s", str);
313	printk(" on CPU%d, ip %08lx, registers:\n",
314	smp_processor_id(), regs->ip);
315	show_registers(regs);
316	oops_end(flags, regs, 0);
317	if (do_panic \|\| panic_on_oops)
318	panic("Non maskable interrupt");
319	nmi_exit();
320	local_irq_enable();
321	do_exit(SIGBUS);
322	}
323
324	static int __init oops_setup(char *s)
325	{
326	if (!s)
327	return -EINVAL;
328	if (!strcmp(s, "panic"))
329	panic_on_oops = 1;
330	return 0;
331	}
332	early_param("oops", oops_setup);
333
334	static int __init kstack_setup(char *s)
335	{
336	if (!s)
337	return -EINVAL;
338	kstack_depth_to_print = simple_strtoul(s, NULL, 0);
339	return 0;
340	}
341	early_param("kstack", kstack_setup);
342
343	static int __init code_bytes_setup(char *s)
344	{
345	code_bytes = simple_strtoul(s, NULL, 0);
346	if (code_bytes > 8192)
347	code_bytes = 8192;
348
349	return 1;
350	}
351	__setup("code_bytes=", code_bytes_setup);