[PATCH] block: fix locking in bdev_del_partition

[Dmitriy Gorokh <degifted@xxxxxxxxx>]

Hi Christoph,

Unfortunately this fix (Upstream commit
08fc1ab6d748ab1a690fd483f41e2938984ce353) breaks compatibility with
some userspace tools, specifically mdadm, who expect ENXIO errno as a
result of BLKPG_DEL_PARTITION operation to test if the block device is
a whole-disk or a partition. With the recent 5.8 kernel it now returns
ENOMEM on an existing block device which seems inconsistent.

Regards,
Dmitriy