[PATCH] xfs_mkfs: wipe old signatures from the device

[Karel Zak]

On Wed, Feb 13, 2013 at 11:41:08AM +0100, Lukáš Czerner wrote:
> However
> 
> mkfs.btrfs /dev/sda
> mkfs.ext4 -F /dev/sda
> 
> works well, however I am not sure why that is. Is that some kind of
> mount(8) magic ?

 This is bug in libmount. Fixed in upstream tree. The libmount in some
 cases ignores the ambivalent probing result from libblkid and tries 
 stuff from /etc/filesystems (where is for example ext4).

> So I think that liblkid _and_ btrfs tools has to be fixed not to treat
> backup superblocks as primary!

 The problem with additional btrfs superblocks has been already reported
 to btrfs guys:

   http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg20957.html

 and I don't see a reply "yep, this is btrfs-progs bug" :-)

    Karel

-- 
 Karel Zak  <kzak at redhat.com>
 http://karelzak.blogspot.com