• NeilBrown's avatar
    md/raid5: don't include 'spare' drives when reshaping to fewer devices. · 3424bf6a
    NeilBrown authored
    There are few situations where it would make any sense to add a spare
    when reducing the number of devices in an array, but it is
    conceivable:  A 6 drive RAID6 with two missing devices could be
    reshaped to a 5 drive RAID6, and a spare could become available
    just in time for the reshape, but not early enough to have been
    recovered first.  'freezing' recovery can make this easy to
    do without any races.
    
    However doing such a thing is a bad idea.  md will not record the
    partially-recovered state of the 'spare' and when the reshape
    finished it will think that the spare is still spare.
    Easiest way to avoid this confusion is to simply disallow it.
    Signed-off-by: default avatarNeilBrown <neilb@suse.de>
    3424bf6a
raid5.c 168 KB