[PATCH] nvme: fix double blk_mq_complete_request for timeout request with low probability

[Keith Busch]

On Thu, Apr 06, 2023 at 04:18:18PM +0000, Lei Lei2 Yin wrote:
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 53ef028596c6..c1cc384f4f3e 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -450,8 +450,8 @@ bool nvme_cancel_request(struct request *req, void *data)
>  	dev_dbg_ratelimited(((struct nvme_ctrl *) data)->device,
>  				"Cancelling I/O %d", req->tag);
>  
> -	/* don't abort one completed request */
> -	if (blk_mq_request_completed(req))
> +	/* don't abort one completed or idle request */
> +	if (blk_mq_rq_state(req) != MQ_RQ_IN_FLIGHT)
>  		return true;

I was suspicious about this path too, and had the same change long ago, but
shelved it when I couldn't produce any errors there. But the change makes sense
to me!

Reviewed-by: Keith Busch <kbusch at kernel.org>