From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: BTRFS partition usage...
Date: Tue, 12 Feb 2008 15:28:26 -0800 (PST)
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From: Jan Engelhardt <jengelh@computergmbh.de>
Date: Tue, 12 Feb 2008 15:00:20 +0100 (CET)

> Something looks wrong here. Why would btrfs need to zero at all?

So that existing superblocks on the partition won't
be interpreted as correct by other filesystems.  It's
a safety measure many mkfs programs use.

> Superblock at 0, and done. Just like xfs.

No, we won't do stupid things like that and make an entire
cylinder of our disks unusable.  See my other reply.