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>
This commit is contained in:
Shaohua Li 2013-11-19 18:57:24 -07:00 committed by Jens Axboe
parent 94eddfbeaa
commit f02b9ac35a

View file

@ -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;
}