diff options
| author | Christoph Hellwig <hch@lst.de> | 2014-09-16 23:44:07 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2014-09-22 19:55:19 +0200 |
| commit | a57a178a490345c7236b0077b3de005754389ed6 (patch) | |
| tree | 7d5fa8c1c9df7a70e367f78297545c253c890926 | |
| parent | blk-mq: Avoid race condition with uninitialized requests (diff) | |
| download | linux-a57a178a490345c7236b0077b3de005754389ed6.tar.xz linux-a57a178a490345c7236b0077b3de005754389ed6.zip | |
blk-mq: avoid infinite recursion with the FUA flag
We should not insert requests into the flush state machine from
blk_mq_insert_request. All incoming flush requests come through
blk_{m,s}q_make_request and are handled there, while blk_execute_rq_nowait
should only be called for BLOCK_PC requests. All other callers
deal with requests that already went through the flush statemchine
and shouldn't be reinserted into it.
Reported-by: Robert Elliott <Elliott@hp.com>
Debugged-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | block/blk-exec.c | 1 | ||||
| -rw-r--r-- | block/blk-mq.c | 11 |
2 files changed, 4 insertions, 8 deletions
diff --git a/block/blk-exec.c b/block/blk-exec.c index f4d27b12c90b..9924725fa50d 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -56,6 +56,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, bool is_pm_resume; WARN_ON(irqs_disabled()); + WARN_ON(rq->cmd_type == REQ_TYPE_FS); rq->rq_disk = bd_disk; rq->end_io = done; diff --git a/block/blk-mq.c b/block/blk-mq.c index 1583ed28ea03..a7d70a1bbf36 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -963,14 +963,9 @@ void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, hctx = q->mq_ops->map_queue(q, ctx->cpu); - if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA) && - !(rq->cmd_flags & (REQ_FLUSH_SEQ))) { - blk_insert_flush(rq); - } else { - spin_lock(&ctx->lock); - __blk_mq_insert_request(hctx, rq, at_head); - spin_unlock(&ctx->lock); - } + spin_lock(&ctx->lock); + __blk_mq_insert_request(hctx, rq, at_head); + spin_unlock(&ctx->lock); if (run_queue) blk_mq_run_hw_queue(hctx, async); |