From e6e7f7ac03e40795346f1b2994a05f507ad8d345 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Fri, 27 Oct 2023 10:58:12 -0700 Subject: nvme: ensure reset state check ordering A different CPU may be setting the ctrl->state value, so ensure proper barriers to prevent optimizing to a stale state. Normally it isn't a problem to observe the wrong state as it is merely advisory to take a quicker path during initialization and error recovery, but seeing an old state can report unexpected ENETRESET errors when a reset request was in fact successful. Reported-by: Minh Hoang Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch Signed-off-by: Hannes Reinecke --- drivers/nvme/host/tcp.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) (limited to 'drivers/nvme/host/tcp.c') diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index d79811cfa0ce..08805f027810 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -2152,10 +2152,11 @@ static void nvme_tcp_teardown_io_queues(struct nvme_ctrl *ctrl, static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl) { + enum nvme_ctrl_state state = nvme_ctrl_state(ctrl); + /* If we are resetting/deleting then do nothing */ - if (ctrl->state != NVME_CTRL_CONNECTING) { - WARN_ON_ONCE(ctrl->state == NVME_CTRL_NEW || - ctrl->state == NVME_CTRL_LIVE); + if (state != NVME_CTRL_CONNECTING) { + WARN_ON_ONCE(state == NVME_CTRL_NEW || state == NVME_CTRL_LIVE); return; } @@ -2215,8 +2216,10 @@ static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new) * unless we're during creation of a new controller to * avoid races with teardown flow. */ - WARN_ON_ONCE(ctrl->state != NVME_CTRL_DELETING && - ctrl->state != NVME_CTRL_DELETING_NOIO); + enum nvme_ctrl_state state = nvme_ctrl_state(ctrl); + + WARN_ON_ONCE(state != NVME_CTRL_DELETING && + state != NVME_CTRL_DELETING_NOIO); WARN_ON_ONCE(new); ret = -EINVAL; goto destroy_io; @@ -2280,8 +2283,10 @@ static void nvme_tcp_error_recovery_work(struct work_struct *work) if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_CONNECTING)) { /* state change failure is ok if we started ctrl delete */ - WARN_ON_ONCE(ctrl->state != NVME_CTRL_DELETING && - ctrl->state != NVME_CTRL_DELETING_NOIO); + enum nvme_ctrl_state state = nvme_ctrl_state(ctrl); + + WARN_ON_ONCE(state != NVME_CTRL_DELETING && + state != NVME_CTRL_DELETING_NOIO); return; } @@ -2311,8 +2316,10 @@ static void nvme_reset_ctrl_work(struct work_struct *work) if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_CONNECTING)) { /* state change failure is ok if we started ctrl delete */ - WARN_ON_ONCE(ctrl->state != NVME_CTRL_DELETING && - ctrl->state != NVME_CTRL_DELETING_NOIO); + enum nvme_ctrl_state state = nvme_ctrl_state(ctrl); + + WARN_ON_ONCE(state != NVME_CTRL_DELETING && + state != NVME_CTRL_DELETING_NOIO); return; } @@ -2430,7 +2437,7 @@ static enum blk_eh_timer_return nvme_tcp_timeout(struct request *rq) nvme_tcp_queue_id(req->queue), nvme_cid(rq), pdu->hdr.type, opc, nvme_opcode_str(qid, opc, fctype)); - if (ctrl->state != NVME_CTRL_LIVE) { + if (nvme_ctrl_state(ctrl) != NVME_CTRL_LIVE) { /* * If we are resetting, connecting or deleting we should * complete immediately because we may block controller -- cgit v1.2.3