[mirror_ubuntu-jammy-kernel.git] / kernel / stacktrace.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * kernel/stacktrace.c
 *
 * Stack trace management functions
 *
 *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 */
#include <linux/sched/task_stack.h>
#include <linux/sched/debug.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/kallsyms.h>
#include <linux/stacktrace.h>

/**
 * stack_trace_print - Print the entries in the stack trace
 * @entries:	Pointer to storage array
 * @nr_entries:	Number of entries in the storage array
 * @spaces:	Number of leading spaces to print
 */
void stack_trace_print(const unsigned long *entries, unsigned int nr_entries,
		       int spaces)
{
	unsigned int i;

	if (WARN_ON(!entries))
		return;

	for (i = 0; i < nr_entries; i++)
		printk("%*c%pS\n", 1 + spaces, ' ', (void *)entries[i]);
}
EXPORT_SYMBOL_GPL(stack_trace_print);

/**
 * stack_trace_snprint - Print the entries in the stack trace into a buffer
 * @buf:	Pointer to the print buffer
 * @size:	Size of the print buffer
 * @entries:	Pointer to storage array
 * @nr_entries:	Number of entries in the storage array
 * @spaces:	Number of leading spaces to print
 *
 * Return: Number of bytes printed.
 */
int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries,
			unsigned int nr_entries, int spaces)
{
	unsigned int generated, i, total = 0;

	if (WARN_ON(!entries))
		return 0;

	for (i = 0; i < nr_entries && size; i++) {
		generated = snprintf(buf, size, "%*c%pS\n", 1 + spaces, ' ',
				     (void *)entries[i]);

		total += generated;
		if (generated >= size) {
			buf += size;
			size = 0;
		} else {
			buf += generated;
			size -= generated;
		}
	}

	return total;
}
EXPORT_SYMBOL_GPL(stack_trace_snprint);

#ifdef CONFIG_ARCH_STACKWALK

struct stacktrace_cookie {
	unsigned long	*store;
	unsigned int	size;
	unsigned int	skip;
	unsigned int	len;
};

static bool stack_trace_consume_entry(void *cookie, unsigned long addr)
{
	struct stacktrace_cookie *c = cookie;

	if (c->len >= c->size)
		return false;

	if (c->skip > 0) {
		c->skip--;
		return true;
	}
	c->store[c->len++] = addr;
	return c->len < c->size;
}

static bool stack_trace_consume_entry_nosched(void *cookie, unsigned long addr)
{
	if (in_sched_functions(addr))
		return true;
	return stack_trace_consume_entry(cookie, addr);
}

/**
 * stack_trace_save - Save a stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored.
 */
unsigned int stack_trace_save(unsigned long *store, unsigned int size,
			      unsigned int skipnr)
{
	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	struct stacktrace_cookie c = {
		.store	= store,
		.size	= size,
		.skip	= skipnr + 1,
	};

	arch_stack_walk(consume_entry, &c, current, NULL);
	return c.len;
}
EXPORT_SYMBOL_GPL(stack_trace_save);

/**
 * stack_trace_save_tsk - Save a task stack trace into a storage array
 * @task:	The task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored.
 */
unsigned int stack_trace_save_tsk(struct task_struct *tsk, unsigned long *store,
				  unsigned int size, unsigned int skipnr)
{
	stack_trace_consume_fn consume_entry = stack_trace_consume_entry_nosched;
	struct stacktrace_cookie c = {
		.store	= store,
		.size	= size,
		/* skip this function if they are tracing us */
		.skip	= skipnr + (current == tsk),
	};

	if (!try_get_task_stack(tsk))
		return 0;

	arch_stack_walk(consume_entry, &c, tsk, NULL);
	put_task_stack(tsk);
	return c.len;
}

/**
 * stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array
 * @regs:	Pointer to pt_regs to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored.
 */
unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
				   unsigned int size, unsigned int skipnr)
{
	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	struct stacktrace_cookie c = {
		.store	= store,
		.size	= size,
		.skip	= skipnr,
	};

	arch_stack_walk(consume_entry, &c, current, regs);
	return c.len;
}

#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
/**
 * stack_trace_save_tsk_reliable - Save task stack with verification
 * @tsk:	Pointer to the task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return:	An error if it detects any unreliable features of the
 *		stack. Otherwise it guarantees that the stack trace is
 *		reliable and returns the number of entries stored.
 *
 * If the task is not 'current', the caller *must* ensure the task is inactive.
 */
int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,
				  unsigned int size)
{
	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	struct stacktrace_cookie c = {
		.store	= store,
		.size	= size,
	};
	int ret;

	/*
	 * If the task doesn't have a stack (e.g., a zombie), the stack is
	 * "reliably" empty.
	 */
	if (!try_get_task_stack(tsk))
		return 0;

	ret = arch_stack_walk_reliable(consume_entry, &c, tsk);
	put_task_stack(tsk);
	return ret ? ret : c.len;
}
#endif

#ifdef CONFIG_USER_STACKTRACE_SUPPORT
/**
 * stack_trace_save_user - Save a user space stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return: Number of trace entries stored.
 */
unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
{
	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	struct stacktrace_cookie c = {
		.store	= store,
		.size	= size,
	};
	mm_segment_t fs;

	/* Trace user stack if not a kernel thread */
	if (current->flags & PF_KTHREAD)
		return 0;

	fs = force_uaccess_begin();
	arch_stack_walk_user(consume_entry, &c, task_pt_regs(current));
	force_uaccess_end(fs);

	return c.len;
}
#endif

#else /* CONFIG_ARCH_STACKWALK */

/*
 * Architectures that do not implement save_stack_trace_*()
 * get these weak aliases and once-per-bootup warnings
 * (whenever this facility is utilized - for example by procfs):
 */
__weak void
save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
	WARN_ONCE(1, KERN_INFO "save_stack_trace_tsk() not implemented yet.\n");
}

__weak void
save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
{
	WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");
}

/**
 * stack_trace_save - Save a stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save(unsigned long *store, unsigned int size,
			      unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		.skip		= skipnr + 1,
	};

	save_stack_trace(&trace);
	return trace.nr_entries;
}
EXPORT_SYMBOL_GPL(stack_trace_save);

/**
 * stack_trace_save_tsk - Save a task stack trace into a storage array
 * @task:	The task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save_tsk(struct task_struct *task,
				  unsigned long *store, unsigned int size,
				  unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		/* skip this function if they are tracing us */
		.skip	= skipnr + (current == task),
	};

	save_stack_trace_tsk(task, &trace);
	return trace.nr_entries;
}

/**
 * stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array
 * @regs:	Pointer to pt_regs to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
				   unsigned int size, unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		.skip		= skipnr,
	};

	save_stack_trace_regs(regs, &trace);
	return trace.nr_entries;
}

#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
/**
 * stack_trace_save_tsk_reliable - Save task stack with verification
 * @tsk:	Pointer to the task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return:	An error if it detects any unreliable features of the
 *		stack. Otherwise it guarantees that the stack trace is
 *		reliable and returns the number of entries stored.
 *
 * If the task is not 'current', the caller *must* ensure the task is inactive.
 */
int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,
				  unsigned int size)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
	};
	int ret = save_stack_trace_tsk_reliable(tsk, &trace);

	return ret ? ret : trace.nr_entries;
}
#endif

#ifdef CONFIG_USER_STACKTRACE_SUPPORT
/**
 * stack_trace_save_user - Save a user space stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
	};

	save_stack_trace_user(&trace);
	return trace.nr_entries;
}
#endif /* CONFIG_USER_STACKTRACE_SUPPORT */

#endif /* !CONFIG_ARCH_STACKWALK */
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
8637c099 IM	2	/*
	3	* kernel/stacktrace.c
	4	*
	5	* Stack trace management functions
	6	*
	7	* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
	8	*/
214d8ca6 TG	9	#include <linux/sched/task_stack.h>
214d8ca6 TG	10	#include <linux/sched/debug.h>
8637c099	11	#include <linux/sched.h>
9212ddb5	12	#include <linux/kernel.h>
9984de1a	13	#include <linux/export.h>
8637c099 IM	14	#include <linux/kallsyms.h>
	15	#include <linux/stacktrace.h>
	16
e9b98e16 TG	17	/**
	18	* stack_trace_print - Print the entries in the stack trace
	19	* @entries: Pointer to storage array
	20	* @nr_entries: Number of entries in the storage array
	21	* @spaces: Number of leading spaces to print
	22	*/
a2970421	23	void stack_trace_print(const unsigned long *entries, unsigned int nr_entries,
e9b98e16	24	int spaces)
8637c099	25	{
e9b98e16	26	unsigned int i;
8637c099	27
e9b98e16	28	if (WARN_ON(!entries))
bfeeeeb9 JB	29	return;
bfeeeeb9 JB	30
e9b98e16 TG	31	for (i = 0; i < nr_entries; i++)
	32	printk("%c%pS\n", 1 + spaces, ' ', (void )entries[i]);
	33	}
	34	EXPORT_SYMBOL_GPL(stack_trace_print);
	35
e9b98e16 TG	36	/**
	37	* stack_trace_snprint - Print the entries in the stack trace into a buffer
	38	* @buf: Pointer to the print buffer
	39	* @size: Size of the print buffer
	40	* @entries: Pointer to storage array
	41	* @nr_entries: Number of entries in the storage array
	42	* @spaces: Number of leading spaces to print
	43	*
	44	* Return: Number of bytes printed.
	45	*/
a2970421	46	int stack_trace_snprint(char buf, size_t size, const unsigned long entries,
e9b98e16	47	unsigned int nr_entries, int spaces)
9a92a6ce	48	{
e9b98e16	49	unsigned int generated, i, total = 0;
9a92a6ce	50
e9b98e16	51	if (WARN_ON(!entries))
9a92a6ce JK	52	return 0;
9a92a6ce JK	53
e9b98e16	54	for (i = 0; i < nr_entries && size; i++) {
bfeda41d	55	generated = snprintf(buf, size, "%*c%pS\n", 1 + spaces, ' ',
e9b98e16	56	(void *)entries[i]);
9a92a6ce JK	57
9a92a6ce JK	58	total += generated;
9a92a6ce JK	59	if (generated >= size) {
	60	buf += size;
	61	size = 0;
	62	} else {
	63	buf += generated;
	64	size -= generated;
	65	}
	66	}
	67
	68	return total;
	69	}
e9b98e16 TG	70	EXPORT_SYMBOL_GPL(stack_trace_snprint);
e9b98e16 TG	71
214d8ca6 TG	72	#ifdef CONFIG_ARCH_STACKWALK
	73
	74	struct stacktrace_cookie {
	75	unsigned long *store;
	76	unsigned int size;
	77	unsigned int skip;
	78	unsigned int len;
	79	};
	80
264c03a2	81	static bool stack_trace_consume_entry(void *cookie, unsigned long addr)
214d8ca6 TG	82	{
	83	struct stacktrace_cookie *c = cookie;
	84
	85	if (c->len >= c->size)
	86	return false;
	87
	88	if (c->skip > 0) {
	89	c->skip--;
	90	return true;
	91	}
	92	c->store[c->len++] = addr;
	93	return c->len < c->size;
	94	}
	95
264c03a2	96	static bool stack_trace_consume_entry_nosched(void *cookie, unsigned long addr)
214d8ca6 TG	97	{
	98	if (in_sched_functions(addr))
	99	return true;
264c03a2	100	return stack_trace_consume_entry(cookie, addr);
214d8ca6 TG	101	}
	102
	103	/**
	104	* stack_trace_save - Save a stack trace into a storage array
	105	* @store: Pointer to storage array
	106	* @size: Size of the storage array
	107	* @skipnr: Number of entries to skip at the start of the stack trace
	108	*
	109	* Return: Number of trace entries stored.
	110	*/
	111	unsigned int stack_trace_save(unsigned long *store, unsigned int size,
	112	unsigned int skipnr)
	113	{
	114	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	115	struct stacktrace_cookie c = {
	116	.store = store,
	117	.size = size,
	118	.skip = skipnr + 1,
	119	};
	120
	121	arch_stack_walk(consume_entry, &c, current, NULL);
	122	return c.len;
	123	}
	124	EXPORT_SYMBOL_GPL(stack_trace_save);
	125
	126	/**
	127	* stack_trace_save_tsk - Save a task stack trace into a storage array
	128	* @task: The task to examine
	129	* @store: Pointer to storage array
	130	* @size: Size of the storage array
	131	* @skipnr: Number of entries to skip at the start of the stack trace
	132	*
	133	* Return: Number of trace entries stored.
	134	*/
	135	unsigned int stack_trace_save_tsk(struct task_struct tsk, unsigned long store,
	136	unsigned int size, unsigned int skipnr)
	137	{
	138	stack_trace_consume_fn consume_entry = stack_trace_consume_entry_nosched;
	139	struct stacktrace_cookie c = {
	140	.store = store,
	141	.size = size,
b0c51f15	142	/* skip this function if they are tracing us */
4b48512c	143	.skip = skipnr + (current == tsk),
214d8ca6 TG	144	};
	145
	146	if (!try_get_task_stack(tsk))
	147	return 0;
	148
	149	arch_stack_walk(consume_entry, &c, tsk, NULL);
	150	put_task_stack(tsk);
	151	return c.len;
	152	}
	153
	154	/**
	155	* stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array
	156	* @regs: Pointer to pt_regs to examine
	157	* @store: Pointer to storage array
	158	* @size: Size of the storage array
	159	* @skipnr: Number of entries to skip at the start of the stack trace
	160	*
	161	* Return: Number of trace entries stored.
	162	*/
	163	unsigned int stack_trace_save_regs(struct pt_regs regs, unsigned long store,
	164	unsigned int size, unsigned int skipnr)
	165	{
	166	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	167	struct stacktrace_cookie c = {
	168	.store = store,
	169	.size = size,
	170	.skip = skipnr,
	171	};
	172
	173	arch_stack_walk(consume_entry, &c, current, regs);
	174	return c.len;
	175	}
	176
	177	#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
	178	/**
	179	* stack_trace_save_tsk_reliable - Save task stack with verification
	180	* @tsk: Pointer to the task to examine
	181	* @store: Pointer to storage array
	182	* @size: Size of the storage array
	183	*
	184	* Return: An error if it detects any unreliable features of the
	185	* stack. Otherwise it guarantees that the stack trace is
	186	* reliable and returns the number of entries stored.
	187	*
	188	* If the task is not 'current', the caller must ensure the task is inactive.
	189	*/
	190	int stack_trace_save_tsk_reliable(struct task_struct tsk, unsigned long store,
	191	unsigned int size)
	192	{
	193	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	194	struct stacktrace_cookie c = {
	195	.store = store,
	196	.size = size,
	197	};
	198	int ret;
	199
	200	/*
	201	* If the task doesn't have a stack (e.g., a zombie), the stack is
	202	* "reliably" empty.
	203	*/
	204	if (!try_get_task_stack(tsk))
	205	return 0;
	206
	207	ret = arch_stack_walk_reliable(consume_entry, &c, tsk);
208	put_task_stack(tsk);
7eaf51a2	209	return ret ? ret : c.len;
214d8ca6 TG	210	}
	211	#endif
	212
	213	#ifdef CONFIG_USER_STACKTRACE_SUPPORT
	214	/**
	215	* stack_trace_save_user - Save a user space stack trace into a storage array
	216	* @store: Pointer to storage array
	217	* @size: Size of the storage array
	218	*
	219	* Return: Number of trace entries stored.
	220	*/
	221	unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
	222	{
	223	stack_trace_consume_fn consume_entry = stack_trace_consume_entry;
	224	struct stacktrace_cookie c = {
	225	.store = store,
	226	.size = size,
	227	};
cac9b9a4	228	mm_segment_t fs;
214d8ca6 TG	229
214d8ca6 TG	230	/* Trace user stack if not a kernel thread */
7e8e6816	231	if (current->flags & PF_KTHREAD)
214d8ca6 TG	232	return 0;
214d8ca6 TG	233
3d13f313	234	fs = force_uaccess_begin();
214d8ca6	235	arch_stack_walk_user(consume_entry, &c, task_pt_regs(current));
3d13f313	236	force_uaccess_end(fs);
cac9b9a4	237
214d8ca6 TG	238	return c.len;
	239	}
	240	#endif
	241
	242	#else /* CONFIG_ARCH_STACKWALK */
	243
9212ddb5	244	/*
af085d90 JP	245	* Architectures that do not implement save_stack_trace_*()
af085d90 JP	246	* get these weak aliases and once-per-bootup warnings
c624d33f	247	* (whenever this facility is utilized - for example by procfs):
9212ddb5 IM	248	*/
	249	__weak void
	250	save_stack_trace_tsk(struct task_struct tsk, struct stack_trace trace)
	251	{
	252	WARN_ONCE(1, KERN_INFO "save_stack_trace_tsk() not implemented yet.\n");
	253	}
c624d33f MH	254
	255	__weak void
	256	save_stack_trace_regs(struct pt_regs regs, struct stack_trace trace)
	257	{
	258	WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");
	259	}
af085d90	260
e9b98e16 TG	261	/**
	262	* stack_trace_save - Save a stack trace into a storage array
	263	* @store: Pointer to storage array
	264	* @size: Size of the storage array
	265	* @skipnr: Number of entries to skip at the start of the stack trace
	266	*
	267	* Return: Number of trace entries stored
	268	*/
	269	unsigned int stack_trace_save(unsigned long *store, unsigned int size,
	270	unsigned int skipnr)
	271	{
	272	struct stack_trace trace = {
	273	.entries = store,
	274	.max_entries = size,
	275	.skip = skipnr + 1,
	276	};
	277
	278	save_stack_trace(&trace);
	279	return trace.nr_entries;
	280	}
	281	EXPORT_SYMBOL_GPL(stack_trace_save);
	282
	283	/**
	284	* stack_trace_save_tsk - Save a task stack trace into a storage array
	285	* @task: The task to examine
	286	* @store: Pointer to storage array
	287	* @size: Size of the storage array
	288	* @skipnr: Number of entries to skip at the start of the stack trace
	289	*
	290	* Return: Number of trace entries stored
	291	*/
	292	unsigned int stack_trace_save_tsk(struct task_struct *task,
	293	unsigned long *store, unsigned int size,
	294	unsigned int skipnr)
	295	{
	296	struct stack_trace trace = {
	297	.entries = store,
	298	.max_entries = size,
b0c51f15	299	/* skip this function if they are tracing us */
4b48512c	300	.skip = skipnr + (current == task),
e9b98e16 TG	301	};
	302
	303	save_stack_trace_tsk(task, &trace);
	304	return trace.nr_entries;
	305	}
	306
	307	/**
	308	* stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array
	309	* @regs: Pointer to pt_regs to examine
	310	* @store: Pointer to storage array
	311	* @size: Size of the storage array
	312	* @skipnr: Number of entries to skip at the start of the stack trace
	313	*
	314	* Return: Number of trace entries stored
	315	*/
	316	unsigned int stack_trace_save_regs(struct pt_regs regs, unsigned long store,
	317	unsigned int size, unsigned int skipnr)
	318	{
	319	struct stack_trace trace = {
	320	.entries = store,
	321	.max_entries = size,
	322	.skip = skipnr,
	323	};
	324
	325	save_stack_trace_regs(regs, &trace);
	326	return trace.nr_entries;
	327	}
	328
	329	#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
	330	/**
	331	* stack_trace_save_tsk_reliable - Save task stack with verification
	332	* @tsk: Pointer to the task to examine
	333	* @store: Pointer to storage array
	334	* @size: Size of the storage array
	335	*
	336	* Return: An error if it detects any unreliable features of the
	337	* stack. Otherwise it guarantees that the stack trace is
	338	* reliable and returns the number of entries stored.
	339	*
	340	* If the task is not 'current', the caller must ensure the task is inactive.
	341	*/
	342	int stack_trace_save_tsk_reliable(struct task_struct tsk, unsigned long store,
	343	unsigned int size)
	344	{
	345	struct stack_trace trace = {
	346	.entries = store,
	347	.max_entries = size,
	348	};
	349	int ret = save_stack_trace_tsk_reliable(tsk, &trace);
	350
	351	return ret ? ret : trace.nr_entries;
	352	}
	353	#endif
	354
	355	#ifdef CONFIG_USER_STACKTRACE_SUPPORT
	356	/**
	357	* stack_trace_save_user - Save a user space stack trace into a storage array
	358	* @store: Pointer to storage array
	359	* @size: Size of the storage array
	360	*
	361	* Return: Number of trace entries stored
	362	*/
	363	unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
	364	{
365	struct stack_trace trace = {
366	.entries = store,
367	.max_entries = size,
368	};
369
370	save_stack_trace_user(&trace);
371	return trace.nr_entries;
372	}
373	#endif /* CONFIG_USER_STACKTRACE_SUPPORT */
214d8ca6 TG	374
214d8ca6 TG	375	#endif /* !CONFIG_ARCH_STACKWALK */