[Savannah-hackers-public] Re: [gnu.org #494134] Savannah colonialone - vcs-noshell issues

[Sylvain Beucler]

On Wed, Oct 21, 2009 at 10:15:07PM +0200, Sylvain Beucler wrote:
> On Wed, Oct 21, 2009 at 04:12:18PM -0400, Daniel Clark via RT wrote:
> > ward had the idea that maybe a domU was using the filesystem and someone
> > simultaneously did a mount from the dom0. As far as we know there is no
> > way to tell if a device is being used by a domU without the xen-specific
> > tools. 
> > 
> > Does that sound like a possibility?
> 
> No. Xen now checks this, it fails when you try to do so.
> Even then I checked that this wasn't the case.
> 
> A LVM snapshot of the volume was temporarily created for backup
> purpose, while the original volume was being used by Xen. I expect
> this to work without issues (to the least it does for the
> download+arch+bzr system).

Ah, looking again at the backup script the error is as Ward suggested,
as the script mounted the original volume rather than the
LVM snapshot. Despite being a read-only process, it must have writing
things like 'atime' and caused corruption.

So the blame is all on me.

-- 
Sylvain