Re: [PATCH v2 09/14] nvme: Implement cross-controller reset completion

Hannes Reinecke
2026-02-03T05:22:47Z

On 1/30/26 23:34, Mohamed Khalfella wrote:
> An nvme source controller that issues CCR command expects to receive an
> NVME_AER_NOTICE_CCR_COMPLETED when pending CCR succeeds or fails. Add
> sctrl->ccr_work to read NVME_LOG_CCR logpage and wakeup any thread
> waiting on CCR completion.
>
> Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
> ---
> drivers/nvme/host/core.c | 49 +++++++++++++++++++++++++++++++++++++++-
> drivers/nvme/host/nvme.h | 1 +
> 2 files changed, 49 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 13e0775d56b4..0f90feb46369 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1901,7 +1901,8 @@ EXPORT_SYMBOL_GPL(nvme_set_queue_count);
>
> #define NVME_AEN_SUPPORTED \
> (NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_FW_ACT | \
> - NVME_AEN_CFG_ANA_CHANGE | NVME_AEN_CFG_DISC_CHANGE)
> + NVME_AEN_CFG_ANA_CHANGE | NVME_AEN_CFG_CCR_COMPLETE | \
> + NVME_AEN_CFG_DISC_CHANGE)
>
> static void nvme_enable_aen(struct nvme_ctrl *ctrl)
> {
> @@ -4866,6 +4867,47 @@ static void nvme_get_fw_slot_info(struct nvme_ctrl *ctrl)
> kfree(log);
> }
>
> +static void nvme_ccr_work(struct work_struct *work)
> +{
> + struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ccr_work);
> + struct nvme_ccr_entry *ccr;
> + struct nvme_ccr_log_entry *entry;
> + struct nvme_ccr_log *log;
> + unsigned long flags;
> + int ret, i;
> +
> + log = kmalloc(sizeof(*log), GFP_KERNEL);
> + if (!log)
> + return;
> +
> + ret = nvme_get_log(ctrl, 0, NVME_LOG_CCR, 0x01,
> + 0x00, log, sizeof(*log), 0);
> + if (ret)
> + goto out;
> +
> + spin_lock_irqsave(&ctrl->lock, flags);
> + for (i = 0; i < le16_to_cpu(log->ne); i++) {
> + entry = &log->entries[i];
> + if (entry->ccrs == NVME_CCR_STATUS_IN_PROGRESS)
> + continue;
> +
> + list_for_each_entry(ccr, &ctrl->ccr_list, list) {
> + struct nvme_ctrl *ictrl = ccr->ictrl;
> +
> + if (ictrl->cntlid != le16_to_cpu(entry->icid) ||
> + ictrl->ciu != entry->ciu)
> + continue;
> +
> + /* Complete matching entry */
> + ccr->ccrs = entry->ccrs;
> + complete(&ccr->complete);
> + }
> + }
> + spin_unlock_irqrestore(&ctrl->lock, flags);
> +out:
> + kfree(log);
> +}
> +
> static void nvme_fw_act_work(struct work_struct *work)
> {
> struct nvme_ctrl *ctrl = container_of(work,
> @@ -4942,6 +4984,9 @@ static bool nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result)
> case NVME_AER_NOTICE_DISC_CHANGED:
> ctrl->aen_result = result;
> break;
> + case NVME_AER_NOTICE_CCR_COMPLETED:
> + queue_work(nvme_wq, &ctrl->ccr_work);
> + break;
> default:
> dev_warn(ctrl->device, "async event result %08x\n", result);
> }
> @@ -5131,6 +5176,7 @@ void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
> nvme_stop_failfast_work(ctrl);
> flush_work(&ctrl->async_event_work);
> cancel_work_sync(&ctrl->fw_act_work);
> + cancel_work_sync(&ctrl->ccr_work);
> if (ctrl->ops->stop_ctrl)
> ctrl->ops->stop_ctrl(ctrl);
> }
> @@ -5254,6 +5300,7 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
> ctrl->quirks = quirks;
> ctrl->numa_node = NUMA_NO_NODE;
> INIT_WORK(&ctrl->scan_work, nvme_scan_work);
> + INIT_WORK(&ctrl->ccr_work, nvme_ccr_work);
> INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
> INIT_WORK(&ctrl->fw_act_work, nvme_fw_act_work);
> INIT_WORK(&ctrl->delete_work, nvme_delete_ctrl_work);
> diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
> index fa18f580d76a..a7f382e35821 100644
> --- a/drivers/nvme/host/nvme.h
> +++ b/drivers/nvme/host/nvme.h
> @@ -366,6 +366,7 @@ struct nvme_ctrl {
> struct nvme_effects_log *effects;
> struct xarray cels;
> struct work_struct scan_work;
> + struct work_struct ccr_work;
> struct work_struct async_event_work;
> struct delayed_work ka_work;
> struct delayed_work failfast_work;

This confuses me. Why do we call 'complete()' but do not have a
corresponding 'wait_for_completion()' call?

Please merge with the next patch to allow reviewers to have the full
picture.

Cheers,

Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare@suse.de +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich