[linux-lvm] Bug in LVM2 tools

[Alasdair G Kergon]

On Wed, Oct 04, 2006 at 11:05:51PM +0200, Xuân Baldauf wrote:
> I observed an obscure bug in the current LVM2 tools. Observe this:
 
> # vgcreate --physicalextentsize=1k test.vg /dev/loop4

When you have larger PEs, this bug gets lost in the rounding that gets done
for alignment.

> It seems that there is
> space reserved for a second metadata copy at the end of /dev/loop4,

It's not actually related to that - it's simply a mistake in the logic that
means it adjusts for the metadata areas both in pvcreate and then a second
time in vgcreate.  When you run vgremove it now reinstates the full disk
size (a bug fix that was applied) so the subsequent vgcreate only makes a
single (correct) adjustment.  In short, there's confusion of responsibility
between pvcreate and vgcreate for calculating the usable data area size
that holds the PEs.

Alasdair
-- 
agk at redhat.com