Re: block: del_gendisk() vs blk_queue_enter() race condition

[Sergey Senozhatsky <senozhatsky@chromium.org>]

On (24/10/07 18:45), Sergey Senozhatsky wrote:
> +	/*
> +	 * Tell the file system to write back all dirty data and shut down if
> +	 * it hasn't been notified earlier.
> +	 */
> +	if (!test_bit(GD_DEAD, &disk->state))
> +		blk_report_disk_dead(disk, false);
> +	/* TODO: big fat comment */
> +	blk_queue_flag_set(QUEUE_FLAG_DYING, disk->queue);
> +	__blk_mark_disk_dead(disk);
> +
>  	/*
>  	 * Prevent new openers by unlinked the bdev inode.
>  	 */
> @@ -657,18 +667,10 @@ void del_gendisk(struct gendisk *disk)
>  		bdev_unhash(part);
>  	mutex_unlock(&disk->open_mutex);
>  
> -	/*
> -	 * Tell the file system to write back all dirty data and shut down if
> -	 * it hasn't been notified earlier.
> -	 */
> -	if (!test_bit(GD_DEAD, &disk->state))
> -		blk_report_disk_dead(disk, false);
> -
>  	/*
>  	 * Drop all partitions now that the disk is marked dead.
>  	 */
>  	mutex_lock(&disk->open_mutex);
> -	__blk_mark_disk_dead(disk);
>  	xa_for_each_start(&disk->part_tbl, idx, part, 1)
>  		drop_partition(part);
>  	mutex_unlock(&disk->open_mutex);
> @@ -714,6 +716,10 @@ void del_gendisk(struct gendisk *disk)
>  	rq_qos_exit(q);
>  	blk_mq_unquiesce_queue(q);
>  
> +	/* TODO: big fat comment */
> +	if (test_bit(GD_OWNS_QUEUE, &disk->state))

       if (!test_bit()), muppet.

> +		blk_queue_flag_clear(QUEUE_FLAG_DYING, disk->queue);