Commit 399146b8 authored Feb 17, 2016 by Sebastian Parschauer Committed by Shaohua Li Feb 26, 2016

md: Drop sending a change uevent when stopping



When stopping an MD device, then its device node /dev/mdX may still
exist afterwards or it is recreated by udev. The next open() call
can lead to creation of an inoperable MD device. The reason for
this is that a change event (KOBJ_CHANGE) is sent to udev which
races against the remove event (KOBJ_REMOVE) from md_free().
So drop sending the change event.

A change is likely also required in mdadm as many versions send the
change event to udev as well.

Neil mentioned the change event is a workaround for old kernel
Commit: 934d9c23 ("md: destroy partitions and notify udev when md array is stopped.")
new mdadm can handle device remove now, so this isn't required any more.

Cc: NeilBrown <neilb@suse.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Sebastian Parschauer <sebastian.riemer@profitbricks.com>
Signed-off-by: Shaohua Li <shli@fb.com>

parent 6ab2a4b8

drivers/md/md.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -5671,7 +5671,6 @@ static int do_md_stop(struct mddev *mddev, int mode,
		export_array(mddev);

		md_clean(mddev);
		kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
		if (mddev->hold_active == UNTIL_STOP)
		mddev->hold_active = 0;
		}

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