Commit f6c8e432 authored Nov 21, 2018 by Sagi Grimberg Committed by Christoph Hellwig Nov 30, 2018

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 <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed by: James Smart <jsmart2021@gmail.com>
Tested-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

parent 14a1336e

drivers/nvme/host/core.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -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);

Admin message