Hi.

On Fri, Apr 10, 2020 at 07:45:44AM +0200, Christoph Hellwig <hch@lst.de> wrote:
> @@ -496,7 +496,7 @@ int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev)
> -	if (bdev->bd_part_count || bdev->bd_openers)
> +	if (bdev->bd_part_count || bdev->bd_openers > 1)
>  		return -EBUSY;
I noticed this (and the previous patch) change unmasks race between
ioctl(LOOP_SET_STATUS64, ... lo_flags=LO_FLAGS_PARTSCAN ...) and udev
processing loop device uevents. See [1] for details.

Should the condition be changed in the case of newly setup loop devices?
(Or shouldn't the ioctl propagate EBUSY in its return value?)

Thanks,
Michal

[1] https://bugzilla.opensuse.org/show_bug.cgi?id=1169932