Daniel P. Berrange
2007-Sep-27 16:28 UTC
[Xen-devel] PATCH: Don''t clobber VIF ''type'' field when starting a HVM guest
In the Xen 3.1.0 series releases the ''VIF'' config has a ''type'' field which is used to determine if using QEMU''s emulated NIC vs netfront/back. - type=ioemu -> Setup QEMU with an rtl8139 nic - type=netfront -> Setup netback, assuming HVM pv drivers - type is None -> Setup QEMU with rtl8139 nic & netback In Fedora (and libvirt) we default to leaving ''type'' as None, so that users do not have to change the Dom0 guest config simply to install PV drivers in an HVM guest. There is one unfortunate bug though - when you start a managed VM, XenD will re-save its configuration out to disk under /var/lib/xend/domains/[UUID] and in doing so, it converts type=None into type=netfront. This isn''t an immediate problem because the config in memory is never changed & still has correct settings. But some days/months later when the machine is rebooted or XenD is restarted, it reads the config from disk & thus the rtl8139 nic disappears from all your HVM guests :-( The attached patch fixes server/netif.py so that it respects type=None as the rest of the XenD code does. The patch is against xen-3.1-testing.hg but also needs to be applied to xen-unstable.hg Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=| _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel