From: Keith Busch kbusch@kernel.org
[ Upstream commit 4c75f877853cfa81b12374a07208e07b077f39b8 ]
A paused controller is doing critical internal activation work in the background. Prevent subsequent controller resets from occurring during this period by setting the controller state to RESETTING first. A helper function, nvme_try_sched_reset_work(), is introduced for these paths so they may continue with scheduling the reset_work after they've completed their uninterruptible critical section.
Tested-by: Edmund Nadolski edmund.nadolski@intel.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/core.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-)
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index ddd5c72a565ad..95d4f1a6dd795 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -126,6 +126,21 @@ static void nvme_queue_scan(struct nvme_ctrl *ctrl) queue_work(nvme_wq, &ctrl->scan_work); }
+/* + * Use this function to proceed with scheduling reset_work for a controller + * that had previously been set to the resetting state. This is intended for + * code paths that can't be interrupted by other reset attempts. A hot removal + * may prevent this from succeeding. + */ +static int nvme_try_sched_reset(struct nvme_ctrl *ctrl) +{ + if (ctrl->state != NVME_CTRL_RESETTING) + return -EBUSY; + if (!queue_work(nvme_reset_wq, &ctrl->reset_work)) + return -EBUSY; + return 0; +} + int nvme_reset_ctrl(struct nvme_ctrl *ctrl) { if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING)) @@ -3445,13 +3460,13 @@ static void nvme_fw_act_work(struct work_struct *work) if (time_after(jiffies, fw_act_timeout)) { dev_warn(ctrl->device, "Fw activation timeout, reset controller\n"); - nvme_reset_ctrl(ctrl); - break; + nvme_try_sched_reset(ctrl); + return; } msleep(100); }
- if (ctrl->state != NVME_CTRL_LIVE) + if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_LIVE)) return;
nvme_start_queues(ctrl); @@ -3467,7 +3482,13 @@ static void nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result) nvme_queue_scan(ctrl); break; case NVME_AER_NOTICE_FW_ACT_STARTING: - queue_work(nvme_wq, &ctrl->fw_act_work); + /* + * We are (ab)using the RESETTING state to prevent subsequent + * recovery actions from interfering with the controller's + * firmware activation. + */ + if (nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING)) + queue_work(nvme_wq, &ctrl->fw_act_work); break; #ifdef CONFIG_NVME_MULTIPATH case NVME_AER_NOTICE_ANA: