• Michael Lyle's avatar
    bcache: don't attach backing with duplicate UUID · 86755b7a
    Michael Lyle authored
    This can happen e.g. during disk cloning.
    This is an incomplete fix: it does not catch duplicate UUIDs earlier
    when things are still unattached.  It does not unregister the device.
    Further changes to cope better with this are planned but conflict with
    Coly's ongoing improvements to handling device errors.  In the meantime,
    one can manually stop the device after this has happened.
    Attempts to attach a duplicate device result in:
    [  136.372404] loop: module loaded
    [  136.424461] bcache: register_bdev() registered backing device loop0
    [  136.424464] bcache: bch_cached_dev_attach() Tried to attach loop0 but duplicate UUID already attached
    My test procedure is:
      dd if=/dev/sdb1 of=imgfile bs=1024 count=262144
      losetup -f imgfile
    Signed-off-by: default avatarMichael Lyle <mlyle@lyle.org>
    Reviewed-by: default avatarTang Junhui <tang.junhui@zte.com.cn>
    Cc: <stable@vger.kernel.org>
    Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
super.c 52 KB