7f07bbf9bc
[ Upstream commit e8a8a18505 ]
Yang Yang reported the following crash caused by requeueing a flush
request in Kyber:
[ 2.517297] Unable to handle kernel paging request at virtual address ffffffd8071c0b00
...
[ 2.517468] pc : clear_bit+0x18/0x2c
[ 2.517502] lr : sbitmap_queue_clear+0x40/0x228
[ 2.517503] sp : ffffff800832bc60 pstate : 00c00145
...
[ 2.517599] Process ksoftirqd/5 (pid: 51, stack limit = 0xffffff8008328000)
[ 2.517602] Call trace:
[ 2.517606] clear_bit+0x18/0x2c
[ 2.517619] kyber_finish_request+0x74/0x80
[ 2.517627] blk_mq_requeue_request+0x3c/0xc0
[ 2.517637] __scsi_queue_insert+0x11c/0x148
[ 2.517640] scsi_softirq_done+0x114/0x130
[ 2.517643] blk_done_softirq+0x7c/0xb0
[ 2.517651] __do_softirq+0x208/0x3bc
[ 2.517657] run_ksoftirqd+0x34/0x60
[ 2.517663] smpboot_thread_fn+0x1c4/0x2c0
[ 2.517667] kthread+0x110/0x120
[ 2.517669] ret_from_fork+0x10/0x18
This happens because Kyber doesn't track flush requests, so
kyber_finish_request() reads a garbage domain token. Only call the
scheduler's requeue_request() hook if RQF_ELVPRIV is set (like we do for
the finish_request() hook in blk_mq_free_request()). Now that we're
handling it in blk-mq, also remove the check from BFQ.
Reported-by: Yang Yang <yang.yang@vivo.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
89 lines
2.5 KiB
C
89 lines
2.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef BLK_MQ_SCHED_H
|
|
#define BLK_MQ_SCHED_H
|
|
|
|
#include "blk-mq.h"
|
|
#include "blk-mq-tag.h"
|
|
|
|
void blk_mq_sched_free_hctx_data(struct request_queue *q,
|
|
void (*exit)(struct blk_mq_hw_ctx *));
|
|
|
|
void blk_mq_sched_assign_ioc(struct request *rq);
|
|
|
|
void blk_mq_sched_request_inserted(struct request *rq);
|
|
bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,
|
|
unsigned int nr_segs, struct request **merged_request);
|
|
bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
|
|
unsigned int nr_segs);
|
|
bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq);
|
|
void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx);
|
|
void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx);
|
|
|
|
void blk_mq_sched_insert_request(struct request *rq, bool at_head,
|
|
bool run_queue, bool async);
|
|
void blk_mq_sched_insert_requests(struct blk_mq_hw_ctx *hctx,
|
|
struct blk_mq_ctx *ctx,
|
|
struct list_head *list, bool run_queue_async);
|
|
|
|
void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx);
|
|
|
|
int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e);
|
|
void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e);
|
|
void blk_mq_sched_free_requests(struct request_queue *q);
|
|
|
|
static inline bool
|
|
blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
|
|
unsigned int nr_segs)
|
|
{
|
|
if (blk_queue_nomerges(q) || !bio_mergeable(bio))
|
|
return false;
|
|
|
|
return __blk_mq_sched_bio_merge(q, bio, nr_segs);
|
|
}
|
|
|
|
static inline bool
|
|
blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq,
|
|
struct bio *bio)
|
|
{
|
|
struct elevator_queue *e = q->elevator;
|
|
|
|
if (e && e->type->ops.allow_merge)
|
|
return e->type->ops.allow_merge(q, rq, bio);
|
|
|
|
return true;
|
|
}
|
|
|
|
static inline void blk_mq_sched_completed_request(struct request *rq, u64 now)
|
|
{
|
|
struct elevator_queue *e = rq->q->elevator;
|
|
|
|
if (e && e->type->ops.completed_request)
|
|
e->type->ops.completed_request(rq, now);
|
|
}
|
|
|
|
static inline void blk_mq_sched_requeue_request(struct request *rq)
|
|
{
|
|
struct request_queue *q = rq->q;
|
|
struct elevator_queue *e = q->elevator;
|
|
|
|
if ((rq->rq_flags & RQF_ELVPRIV) && e && e->type->ops.requeue_request)
|
|
e->type->ops.requeue_request(rq);
|
|
}
|
|
|
|
static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx)
|
|
{
|
|
struct elevator_queue *e = hctx->queue->elevator;
|
|
|
|
if (e && e->type->ops.has_work)
|
|
return e->type->ops.has_work(hctx);
|
|
|
|
return false;
|
|
}
|
|
|
|
static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx)
|
|
{
|
|
return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
|
|
}
|
|
|
|
#endif
|