Re: [PATCH] block: Fix a deadlock related freezing zoned storage devices

[Bart Van Assche <bvanassche@acm.org>]

On 5/23/25 1:20 AM, Christoph Hellwig wrote:
> Something like this completely untested patch:
> 
> diff --git a/block/blk-zoned.c b/block/blk-zoned.c
> index 8f15d1aa6eb8..6841af8a989c 100644
> --- a/block/blk-zoned.c
> +++ b/block/blk-zoned.c
> @@ -1306,16 +1306,18 @@ static void blk_zone_wplug_bio_work(struct work_struct *work)
>   	spin_unlock_irqrestore(&zwplug->lock, flags);
>   
>   	bdev = bio->bi_bdev;
> -	submit_bio_noacct_nocheck(bio);
> -
>   	/*
>   	 * blk-mq devices will reuse the extra reference on the request queue
>   	 * usage counter we took when the BIO was plugged, but the submission
>   	 * path for BIO-based devices will not do that. So drop this extra
>   	 * reference here.
>   	 */
> -	if (bdev_test_flag(bdev, BD_HAS_SUBMIT_BIO))
> +	if (bdev_test_flag(bdev, BD_HAS_SUBMIT_BIO)) {
> +		bdev->bd_disk->fops->submit_bio(bio);
>   		blk_queue_exit(bdev->bd_disk->queue);
> +	} else {
> +		blk_mq_submit_bio(bio);
> +	}
>   
>   put_zwplug:
>   	/* Drop the reference we took in disk_zone_wplug_schedule_bio_work(). */

This patch works fine on my test setup.

Thanks,

Bart.