Driver should set req->state to MQ_RQ_COMPLETE after it finishes to process req. But virtio-blk doesn't set MQ_RQ_COMPLETE after virtblk_poll() handles req and req->state still remains MQ_RQ_IN_FLIGHT. Fortunately so far there is no issue about it because blk_mq_end_request_batch() sets req->state to MQ_RQ_IDLE. In this patch, virblk_poll() calls blk_mq_complete_request_remote() to set req->state to MQ_RQ_COMPLETE before it adds req to a batch completion list. So it properly sets req->state after polling I/O is finished. Fixes: 4e0400525691 ("virtio-blk: support polling I/O") Signed-off-by: Suwan Kim <suwan.kim027@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> --- drivers/block/virtio_blk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 19da5defd734..75ee51aba964 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -858,9 +858,10 @@ static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) struct request *req = blk_mq_rq_from_pdu(vbr); found++; - if (!blk_mq_add_to_batch(req, iob, vbr->status, + if (!blk_mq_complete_request_remote(req) && + !blk_mq_add_to_batch(req, iob, vbr->status, virtblk_complete_batch)) - blk_mq_complete_request(req); + virtblk_request_done(req); } if (found) -- 2.26.3