Re: [Qemu-devel] Cutting a new QEMU release

[Jamie Lokier <jamie@shareable.org>]

Riku Voipio wrote:
> On Tue, Feb 03, 2009 at 02:48:22PM -0600, Anthony Liguori wrote:
> > We could decide to cut one by the end of the month.
> 
> This would indeed be really cool.
> 
> > .. to decide if there's anything we need to fix before a release.
> 
> At least the OS X (cocoa) host is broken, which is IMHO pretty
> bad regression. Apart from that I'm not aware of any major regression
> (wearing arm-linux-user, some arm-softmmu and debian hats).

I'd say the two qcow2 data corruption bugs are a major regression.
(Both reported in in another thread).

qemu 0.9.1 has the qcow2 code from kvm-72, which doesn't exhibit
either of those corruption bugs.  A new release based on current kvm
userspace would introduce those bugs.  One of the bugs (reported by
Marc) corrupts a qcow2 image so you can't use it even if you revert to
an older qemu/kvm.  It's not clear if the other bug causes permanent
corruption itself, but anything which causes a guest to see the wrong
data can lead to the guest writing corrupt data elsewhere later on.

Simply reverting the qcow2 code appears to fix those problems, so it
needn't hold up cutting a release.  That's what I recommend.

-- Jamie