From 9f98772ba307dd89a3d17dc2589f213d3972fc64 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Mon, 27 Jul 2020 17:32:09 -0700 Subject: [PATCH] nvme-rdma: fix controller reset hang during traffic commit fe35ec58f0d3 ("block: update hctx map when use multiple maps") exposed an issue where we may hang trying to wait for queue freeze during I/O. We call blk_mq_update_nr_hw_queues which in case of multiple queue maps (which we have now for default/read/poll) is attempting to freeze the queue. However we never started queue freeze when starting the reset, which means that we have inflight pending requests that entered the queue that we will not complete once the queue is quiesced. So start a freeze before we quiesce the queue, and unfreeze the queue after we successfully connected the I/O queues (and make sure to call blk_mq_update_nr_hw_queues only after we are sure that the queue was already frozen). This follows to how the pci driver handles resets. Fixes: fe35ec58f0d3 ("block: update hctx map when use multiple maps") Signed-off-by: Sagi Grimberg Signed-off-by: Christoph Hellwig --- drivers/nvme/host/rdma.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index 5c3848974ccb..44c76ffbb264 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -967,15 +967,20 @@ static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new) ret = PTR_ERR(ctrl->ctrl.connect_q); goto out_free_tag_set; } - } else { - blk_mq_update_nr_hw_queues(&ctrl->tag_set, - ctrl->ctrl.queue_count - 1); } ret = nvme_rdma_start_io_queues(ctrl); if (ret) goto out_cleanup_connect_q; + if (!new) { + nvme_start_queues(&ctrl->ctrl); + nvme_wait_freeze(&ctrl->ctrl); + blk_mq_update_nr_hw_queues(ctrl->ctrl.tagset, + ctrl->ctrl.queue_count - 1); + nvme_unfreeze(&ctrl->ctrl); + } + return 0; out_cleanup_connect_q: @@ -1008,6 +1013,7 @@ static void nvme_rdma_teardown_io_queues(struct nvme_rdma_ctrl *ctrl, bool remove) { if (ctrl->ctrl.queue_count > 1) { + nvme_start_freeze(&ctrl->ctrl); nvme_stop_queues(&ctrl->ctrl); nvme_rdma_stop_io_queues(ctrl); if (ctrl->ctrl.tagset) { -- GitLab