diff options
| author |   Shaohua Li <shli@fusionio.com> | 2013-11-19 18:57:24 -0700 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2013-11-19 19:00:45 -0700 |
| commit | f02b9ac35a47dff745c7637fbc095f01cc03646e (patch) | |
| tree | 3615c099998adb4d8b65681acb16d9b060b1ee89 | |
| parent | blk-mq: ensure that we set REQ_IO_STAT so diskstats work (diff) | |
| download | linux-dev-f02b9ac35a47dff745c7637fbc095f01cc03646e.tar.xz linux-dev-f02b9ac35a47dff745c7637fbc095f01cc03646e.zip | |
virtio-blk: virtqueue_kick() must be ordered with other virtqueue operations
It isn't safe to call it without holding the vblk->vq_lock.
Reported-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Shaohua Li <shli@fusionio.com>
Fixed another condition of virtqueue_kick() not holding the lock.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/block/virtio_blk.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 588479d58f52..6a680d4de7f1 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -199,15 +199,16 @@ static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req) spin_lock_irqsave(&vblk->vq_lock, flags); if (__virtblk_add_req(vblk->vq, vbr, vbr->sg, num) < 0) { + virtqueue_kick(vblk->vq); spin_unlock_irqrestore(&vblk->vq_lock, flags); blk_mq_stop_hw_queue(hctx); - virtqueue_kick(vblk->vq); return BLK_MQ_RQ_QUEUE_BUSY; } - spin_unlock_irqrestore(&vblk->vq_lock, flags); if (last) virtqueue_kick(vblk->vq); + + spin_unlock_irqrestore(&vblk->vq_lock, flags); return BLK_MQ_RQ_QUEUE_OK; } |