diff options
| author | Omar Sandoval <osandov@fb.com> | 2017-04-07 08:52:27 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2017-04-07 08:56:48 -0600 |
| commit | 54d5329d425650fafaf90660a139c771d2d49cae (patch) | |
| tree | 3fc6db73809742be0f0fdf403c77af02a6feeeba /block/blk-mq-sched.c | |
| parent | 93252632e828da3e90241a1c0e766556abf71598 (diff) | |
| download | lwn-54d5329d425650fafaf90660a139c771d2d49cae.tar.gz lwn-54d5329d425650fafaf90660a139c771d2d49cae.zip | |
blk-mq-sched: fix crash in switch error path
In elevator_switch(), if blk_mq_init_sched() fails, we attempt to fall
back to the original scheduler. However, at this point, we've already
torn down the original scheduler's tags, so this causes a crash. Doing
the fallback like the legacy elevator path is much harder for mq, so fix
it by just falling back to none, instead.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/blk-mq-sched.c')
| -rw-r--r-- | block/blk-mq-sched.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 0bb13bb51daa..e8c2ed654ef0 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -451,7 +451,7 @@ static int blk_mq_sched_alloc_tags(struct request_queue *q, return ret; } -void blk_mq_sched_teardown(struct request_queue *q) +static void blk_mq_sched_tags_teardown(struct request_queue *q) { struct blk_mq_tag_set *set = q->tag_set; struct blk_mq_hw_ctx *hctx; @@ -513,10 +513,19 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e) return 0; err: - blk_mq_sched_teardown(q); + blk_mq_sched_tags_teardown(q); + q->elevator = NULL; return ret; } +void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e) +{ + if (e->type->ops.mq.exit_sched) + e->type->ops.mq.exit_sched(e); + blk_mq_sched_tags_teardown(q); + q->elevator = NULL; +} + int blk_mq_sched_init(struct request_queue *q) { int ret; |