From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit 5110f40241d08334375eb0495f174b1d2c07657e ]
In the timeout handler we may need to complete a request because the request that timed out may be an I/O that is a part of a serial sequence of controller teardown or initialization. In order to complete the request, we need to fence any other context that may compete with us and complete the request that is timing out.
In this case, we could have a potential double completion in case a hard-irq or a different competing context triggered error recovery and is running inflight request cancellation concurrently with the timeout handler.
Protect using a ctrl teardown_lock to serialize contexts that may complete a cancelled request due to error recovery or a reset.
Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: James Smart james.smart@broadcom.com Signed-off-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/rdma.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index f393a6193252..7e2cdb17c26d 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -118,6 +118,7 @@ struct nvme_rdma_ctrl { struct sockaddr_storage src_addr;
struct nvme_ctrl ctrl; + struct mutex teardown_lock; bool use_inline_data; };
@@ -880,6 +881,7 @@ static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new) static void nvme_rdma_teardown_admin_queue(struct nvme_rdma_ctrl *ctrl, bool remove) { + mutex_lock(&ctrl->teardown_lock); blk_mq_quiesce_queue(ctrl->ctrl.admin_q); nvme_rdma_stop_queue(&ctrl->queues[0]); if (ctrl->ctrl.admin_tagset) @@ -887,11 +889,13 @@ static void nvme_rdma_teardown_admin_queue(struct nvme_rdma_ctrl *ctrl, nvme_cancel_request, &ctrl->ctrl); blk_mq_unquiesce_queue(ctrl->ctrl.admin_q); nvme_rdma_destroy_admin_queue(ctrl, remove); + mutex_unlock(&ctrl->teardown_lock); }
static void nvme_rdma_teardown_io_queues(struct nvme_rdma_ctrl *ctrl, bool remove) { + mutex_lock(&ctrl->teardown_lock); if (ctrl->ctrl.queue_count > 1) { nvme_stop_queues(&ctrl->ctrl); nvme_rdma_stop_io_queues(ctrl); @@ -902,6 +906,7 @@ static void nvme_rdma_teardown_io_queues(struct nvme_rdma_ctrl *ctrl, nvme_start_queues(&ctrl->ctrl); nvme_rdma_destroy_io_queues(ctrl, remove); } + mutex_unlock(&ctrl->teardown_lock); }
static void nvme_rdma_stop_ctrl(struct nvme_ctrl *nctrl) @@ -1955,6 +1960,7 @@ static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev, return ERR_PTR(-ENOMEM); ctrl->ctrl.opts = opts; INIT_LIST_HEAD(&ctrl->list); + mutex_init(&ctrl->teardown_lock);
if (opts->mask & NVMF_OPT_TRSVCID) port = opts->trsvcid;