Re: [Qemu-devel] [PATCH] Disk image shared and exclusive locks.

["Richard W.M. Jones" <rjones@redhat.com>]

On Tue, Dec 08, 2009 at 10:48:17AM +0100, Kevin Wolf wrote:
> Am 07.12.2009 15:31, schrieb Richard W.M. Jones:
> > So to be clear, the use case is that all the other VMs must be shut
> > down, then the VM which wants to commit will upgrade its lock and
> > commit, and then all the other VMs will restart?  I agree this should
> > avoid corruption, although it sounds like something which is fairly
> > unlikely to be done in practice.
> 
> I can't see how the file system of VM2 could possibly survive if VM1
> commits its changes. Even if VM2 or even both VMs are shut down while
> we're corrupting the base image.

Yes, I see, you're correct - even if the VMs are shut down, committing
to the backing file will result in corruption.

Rich.

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