From: James Smart jsmart2021@gmail.com
[ Upstream commit d625d05ef0f0914a706d824fab85472a42be6659 ]
When connectivity is lost to a device, the association is terminated and the blk-mq queues are quiesced/stopped. When connectivity is re-established, they are resumed.
If an admin command is received while connectivity is list, the ioctl queues the command on the admin_q and the command stalls (the thread issuing the ioctl hangs/waits). if the connectivity is lost long enough such that the controller is then deleted, the delete code makes its calls to initiate the delete, which then expects the core layer to call the transport when all references are removed and the controller can be freed. Unfortunately, nothing in this path dequeued the admin command, so a reference sits outstanding and things stop, hanging the delete indefinitely.
Correct by unquiescing the admin queue in the delete association. This means any admin command (which should only be from an ioctl) issued after connectivity is lost will detect the controller is in a reconnecting state and will (fast) fail the command. Thus, a pending reference can no longer be created. Once connectivity is re-established, a new ioctl/admin command would see proper device state and function again.
Signed-off-by: James Smart james.smart@broadcom.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/nvme/host/fc.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c index 794e66e4aa20..8f9ddd0e392c 100644 --- a/drivers/nvme/host/fc.c +++ b/drivers/nvme/host/fc.c @@ -2921,6 +2921,9 @@ nvme_fc_delete_association(struct nvme_fc_ctrl *ctrl) __nvme_fc_delete_hw_queue(ctrl, &ctrl->queues[0], 0); nvme_fc_free_queue(&ctrl->queues[0]);
+ /* re-enable the admin_q so anything new can fast fail */ + blk_mq_unquiesce_queue(ctrl->ctrl.admin_q); + nvme_fc_ctlr_inactive_on_rport(ctrl); }