Re: [PATCHv4 0/3] scsi timeout handling updates

[Keith Busch <keith.busch@intel.com>]

On Wed, Nov 28, 2018 at 09:26:55AM -0700, Keith Busch wrote:
> ---
> diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
> index 9908082b32c4..116398b240e5 100644
> --- a/drivers/nvme/target/loop.c
> +++ b/drivers/nvme/target/loop.c
> @@ -428,10 +428,14 @@ static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
>  static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl)
>  {
>  	if (ctrl->ctrl.queue_count > 1) {
> -		nvme_stop_queues(&ctrl->ctrl);
> -		blk_mq_tagset_busy_iter(&ctrl->tag_set,
> -					nvme_cancel_request, &ctrl->ctrl);
> +		/*
> +		 * The back end device driver is responsible for completing all
> +		 * entered requests
> +		 */
> +		nvme_start_freeze(&ctrl->ctrl);
> +		nvme_wait_freeze(&ctrl->ctrl);
>  		nvme_loop_destroy_io_queues(ctrl);
> +		nvme_unfreeze(&ctrl->ctrl);
>  	}
>  
>  	if (ctrl->ctrl.state == NVME_CTRL_LIVE)
> ---

The above tests fine with io and nvme resets on a target nvme loop
backed by null_blk, but I also couldn't recreate the original report
without the patch.

Ming,

Could you tell me a little more how you set it up? I'm just configuring
null_blk with queue_mode=2 irqmode=2. Anything else to recreate?

Thanks,
Keith