On Tue, Jun 30, 2009 at 03:21:24PM +0100, Paul Brook wrote: > > >>> The qcow block driver format is no longer maintained and likely > > >>> contains > > >>> serious data corruptors. Urge users to stay away for it, and advertise > > >>> the new and improved replacement. > > > > > > I'm not sure how I feel about this. Can we prove qcow is broken? Is > > > it only broken for writes and not reads? > > > > Well, Kevin posted a patch, so it is. It's definitely unmaintained. > > Given it's a qemu native format, there is no interoperability value > > except with old qemu versions. > > > > > If we're printing a warning, does that mean we want to deprecate qcow > > > and eventually remove it (or remove write support, at least)? > > > > Yes. > > IMHO there's little value in just printing a warning. Until it actually goes > away, people are liable to assume we're just being paranoid/awkward and keep > using it anyway. > > I suggest crippling it now and, assuming noone steps up to fix+maintain it, > ripping out the write support altogether at next release. > I'm assuming the readonly code is in better shape, and can be supported with > relatively little effort. I agree, if we want to phase it out we should be more discouraging than just an ignoreable warning - Disable it in qemu, and have code which looks for qcow1 magic bytes, prints an error message telling them to use qemu-img to convert to qcow2 and exits - Keep qcow1 in qemu-img as a source format only, to allow conversions to qcow2 Possibly have a 'configure' arg to let people re-enable full read-write it if they badly need it, but tell them it'll be gone permanently in release qemu-0.12.0 Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
