From 8faeb529b2dabb9df691d614dda18910a43d05c9 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 4 Jun 2014 13:34:58 +0200 Subject: virtio-scsi: fix various bad behavior on aborted requests Even though the virtio-scsi spec guarantees that all requests related to the TMF will have been completed by the time the TMF itself completes, the request queue's callback might not have run yet. This causes requests to be completed more than once, and as a result triggers a variety of BUGs or oopses. Signed-off-by: Paolo Bonzini Reviewed-by: Venkatesh Srinivas Cc: stable@vger.kernel.org Signed-off-by: Christoph Hellwig --- drivers/scsi/virtio_scsi.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index bcad917fd89a..308256b5e4cb 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -237,6 +237,16 @@ static void virtscsi_req_done(struct virtqueue *vq) virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd); }; +static void virtscsi_poll_requests(struct virtio_scsi *vscsi) +{ + int i, num_vqs; + + num_vqs = vscsi->num_queues; + for (i = 0; i < num_vqs; i++) + virtscsi_vq_done(vscsi, &vscsi->req_vqs[i], + virtscsi_complete_cmd); +} + static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf) { struct virtio_scsi_cmd *cmd = buf; @@ -591,6 +601,18 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED) ret = SUCCESS; + /* + * The spec guarantees that all requests related to the TMF have + * been completed, but the callback might not have run yet if + * we're using independent interrupts (e.g. MSI). Poll the + * virtqueues once. + * + * In the abort case, sc->scsi_done will do nothing, because + * the block layer must have detected a timeout and as a result + * REQ_ATOM_COMPLETE has been set. + */ + virtscsi_poll_requests(vscsi); + out: mempool_free(cmd, virtscsi_cmd_pool); return ret; -- cgit v1.2.3