Re: [PATCH v3 3/3] nvme: handle connectivity loss in nvme_set_queue_count

[Hannes Reinecke <hare@suse.de>]

On 11/29/24 10:28, Daniel Wagner wrote:
> When the set feature attempts fails with any NVME status code set in
> nvme_set_queue_count, the function still report success. Though the
> numbers of queues set to 0. This is done to support controllers in
> degraded state (the admin queue is still up and running but no IO
> queues).
> 
> Though there is an exception. When nvme_set_features reports an host
> path error, nvme_set_queue_count should propagate this error as the
> connectivity is lost, which means also the admin queue is not working
> anymore.
> 
> Fixes: 9a0be7abb62f ("nvme: refactor set_queue_count")
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Daniel Wagner <wagi@kernel.org>
> ---
>   drivers/nvme/host/core.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 2a07c2c540b26c8cbe886711abaf6f0afbe6c4df..aa2a7c7d4d0ae7bd1f7fb704e55c0a8d724b9d56 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1677,7 +1677,12 @@ int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
>   
>   	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, NULL, 0,
>   			&result);
> -	if (status < 0)
> +	/*
> +	 * It's either a kernel error or the host observed a connection
> +	 * lost. In either case it's not possible communicate with the
> +	 * controller and thus enter the error code path.
> +	 */
> +	if (status < 0 || status == NVME_SC_HOST_PATH_ERROR)
>   		return status;
>   
>   	/*
> 
Hmm. Maybe checking for NVME_SC_DNR, too?

Otherwise:

Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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