From: Sagi Grimberg Date: Wed, 21 Nov 2018 23:17:37 +0000 (-0800) Subject: nvme: flush namespace scanning work just before removing namespaces X-Git-Tag: v4.20-rc5~5^2^2~1 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=f6c8e432cb0479255322c5d0335b9f1699a0270c;p=linux.git nvme: flush namespace scanning work just before removing namespaces nvme_stop_ctrl can be called also for reset flow and there is no need to flush the scan_work as namespaces are not being removed. This can cause deadlock in rdma, fc and loop drivers since nvme_stop_ctrl barriers before controller teardown (and specifically I/O cancellation of the scan_work itself) takes place, but the scan_work will be blocked anyways so there is no need to flush it. Instead, move scan_work flush to nvme_remove_namespaces() where it really needs to flush. Reported-by: Ming Lei Signed-off-by: Sagi Grimberg Reviewed-by: Keith Busch Reviewed by: James Smart Tested-by: Ewan D. Milne Signed-off-by: Christoph Hellwig --- diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index bb39b91253c2..3cf1b773158e 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -3314,6 +3314,9 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl) struct nvme_ns *ns, *next; LIST_HEAD(ns_list); + /* prevent racing with ns scanning */ + flush_work(&ctrl->scan_work); + /* * The dead states indicates the controller was not gracefully * disconnected. In that case, we won't be able to flush any data while @@ -3476,7 +3479,6 @@ void nvme_stop_ctrl(struct nvme_ctrl *ctrl) nvme_mpath_stop(ctrl); nvme_stop_keep_alive(ctrl); flush_work(&ctrl->async_event_work); - flush_work(&ctrl->scan_work); cancel_work_sync(&ctrl->fw_act_work); if (ctrl->ops->stop_ctrl) ctrl->ops->stop_ctrl(ctrl);