Bug#612439: Bug still exists in current Debian Stable

[Adam Goryachev]

Just wanted to advise that I got bitten by this bug yesterday, using an
up to date debian stable (lvm2 2.02.66-5)

In my case, I couldn't access the snapshot or the underlying LV.

The solution was to install the kernel from debian testing, reboot, let
the merge complete, reboot again to debian stable kernel, un-install new
kernel.

I would propose that a patch is added to debian stable for lvconvert
--merge to confirm support exists in the kernel BEFORE it modifies
anything on disk, and to fail/error/etc.
Or, if easier, just check the kernel version is less than 2.6.33 which I
understand this feature was added to.
Or finally, just always error and warn a newer kernel is probably
needed, add --force to continue.

In any case, I was exceptionally lucky since I did have a copy of the LV
(albeit from 15 hours earlier of upgrades/major system changes/etc), and
that by upgrading I could recover, and successfully downgrade again.

Regards,
Adam

-- 
Adam Goryachev
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