nvme-tcp: fix timeout handler
Currently, we have several problems with the timeout
handler:
1. If we timeout on the controller establishment flow, we will hang
because we don't execute the error recovery (and we shouldn't because
the create_ctrl flow needs to fail and cleanup on its own)
2. We might also hang if we get a disconnet on a queue while the
controller is already deleting. This racy flow can cause the controller
disable/shutdown admin command to hang.
We cannot complete a timed out request from the timeout handler without
mutual exclusion from the teardown flow (e.g. nvme_rdma_error_recovery_work).
So we serialize it in the timeout handler and teardown io and admin
queues to guarantee that no one races with us from completing the
request.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 265a054..5f0a004 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1948,20 +1948,23 @@ nvme_tcp_timeout(struct request *rq, bool reserved)
struct nvme_tcp_ctrl *ctrl = req->queue->ctrl;
struct nvme_tcp_cmd_pdu *pdu = req->pdu;
- dev_dbg(ctrl->ctrl.device,
+ dev_warn(ctrl->ctrl.device,
"queue %d: timeout request %#x type %d\n",
- nvme_tcp_queue_id(req->queue), rq->tag,
- pdu->hdr.type);
+ nvme_tcp_queue_id(req->queue), rq->tag, pdu->hdr.type);
if (ctrl->ctrl.state != NVME_CTRL_LIVE) {
- union nvme_result res = {};
-
- nvme_req(rq)->flags |= NVME_REQ_CANCELLED;
- nvme_end_request(rq, cpu_to_le16(NVME_SC_ABORT_REQ), res);
+ /*
+ * Teardown immediately if controller times out while starting
+ * or we are already started error recovery. all outstanding
+ * requests are completed on shutdown, so we return BLK_EH_DONE.
+ */
+ flush_work(&ctrl->err_work);
+ nvme_tcp_teardown_io_queues(&ctrl->ctrl, false);
+ nvme_tcp_teardown_admin_queue(&ctrl->ctrl, false);
return BLK_EH_DONE;
}
- /* queue error recovery */
+ dev_warn(ctrl->ctrl.device, "starting error recovery\n");
nvme_tcp_error_recovery(&ctrl->ctrl);
return BLK_EH_RESET_TIMER;
