nvme: flush namespace scanning work just before removing namespaces

[ Upstream commit f6c8e432cb0479255322c5d0335b9f1699a0270c ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Sagi Grimberg 2018-11-21 15:17:37 -08:00 committed by Greg Kroah-Hartman
parent 0859bb2526
commit 9407fd14d0

View File

@ -2572,6 +2572,9 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
{
struct nvme_ns *ns, *next;
/* 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
@ -2743,7 +2746,6 @@ void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
{
nvme_stop_keep_alive(ctrl);
flush_work(&ctrl->async_event_work);
flush_work(&ctrl->scan_work);
cancel_work_sync(&ctrl->fw_act_work);
}
EXPORT_SYMBOL_GPL(nvme_stop_ctrl);