[Btrfs-devel] Oops

[Zach Brown]

>> I think btrfs.ko should have a global list of uuids that are mounted.
>> It could then forbid to mount a superblock with a uuid that is already
>> mounted somewhere else.

> Check the XFS code - uuid_table_insert(), uuid_table_remove() and
> xfs_uuid_mount(). it would probably be worthwhile making this a generic
> uuid table and support infrastructure as MD also does some stuff
> with uuids (e.g. uuid_equal()).

That sounds like a fine idea, thanks for the pointer.

> Note, it does mean snapshots have to have different UUIDs to the main
> volume if they are independently mounted (hence xfs_admin -U).

Well, I'm not sure if requiring uuids per snapshot is the right fix but
yes, clearly the check needs to be clever enough to differentiate
between mounting a snapshot in a live volume and activating a volume for
the first time.

- z