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02 December 2022, 17:28:11 UTC
Revision a4412fdd49dc011bcc2c0d81ac4cab7457092650 authored by Steven Rostedt (Google) on 21 November 2022, 15:44:03 UTC, committed by Linus Torvalds on 01 December 2022, 21:14:21 UTC 
error-injection: Add prompt for function error injection
 
The config to be able to inject error codes into any function annotated
with ALLOW_ERROR_INJECTION() is enabled when FUNCTION_ERROR_INJECTION is
enabled.  But unfortunately, this is always enabled on x86 when KPROBES
is enabled, and there's no way to turn it off.

As kprobes is useful for observability of the kernel, it is useful to
have it enabled in production environments.  But error injection should
be avoided.  Add a prompt to the config to allow it to be disabled even
when kprobes is enabled, and get rid of the "def_bool y".

This is a kernel debug feature (it's in Kconfig.debug), and should have
never been something enabled by default.

Cc: stable@vger.kernel.org
Fixes: 540adea3809f6 ("error-injection: Separate error-injection from kprobe")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 355479c
Raw File
Tip revision: a4412fdd49dc011bcc2c0d81ac4cab7457092650 authored by Steven Rostedt (Google) on 21 November 2022, 15:44:03 UTC
error-injection: Add prompt for function error injection
Tip revision: a4412fd
blk-mq-tag.h 
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef INT_BLK_MQ_TAG_H
#define INT_BLK_MQ_TAG_H

struct blk_mq_alloc_data;

extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags,
					unsigned int reserved_tags,
					int node, int alloc_policy);
extern void blk_mq_free_tags(struct blk_mq_tags *tags);
extern int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags,
			       struct sbitmap_queue *breserved_tags,
			       unsigned int queue_depth,
			       unsigned int reserved,
			       int node, int alloc_policy);

extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags,
			      unsigned int *offset);
extern void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
			   unsigned int tag);
void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags);
extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
					struct blk_mq_tags **tags,
					unsigned int depth, bool can_grow);
extern void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set,
					     unsigned int size);
extern void blk_mq_tag_update_sched_shared_tags(struct request_queue *q);

extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn,
		void *priv);
void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
		void *priv);

static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
						 struct blk_mq_hw_ctx *hctx)
{
	if (!hctx)
		return &bt->ws[0];
	return sbq_wait_ptr(bt, &hctx->wait_index);
}

enum {
	BLK_MQ_NO_TAG		= -1U,
	BLK_MQ_TAG_MIN		= 1,
	BLK_MQ_TAG_MAX		= BLK_MQ_NO_TAG - 1,
};

extern void __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);

static inline void blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
{
	if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
		__blk_mq_tag_busy(hctx);
}

static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
{
	if (!(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED))
		return;

	__blk_mq_tag_idle(hctx);
}

static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
					  unsigned int tag)
{
	return tag < tags->nr_reserved_tags;
}

#endif
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