Re: [libvirt] [PATCH 0/2] smbios fixes

On 12/02/2010 05:47 AM, Daniel P. Berrange wrote: > On Wed, Dec 01, 2010 at 05:12:08PM -0700, Eric Blake wrote: >> In testing <smbios mode='host'/>, I noticed a couple of problems. >> First, qemu rejected the command line we gave it (invalid UUID); >> ifixingthat showed that all other arguments were being given literal >> "" which then made the guest smbios differ from the host. Second, >> the qemu option -smbios type=1,family=string wasn't supported, which >> lead to a spurious difference between host and guest. >> >> Meanwhile, qemu has a bug where '-smbios type=1,uuid=uuid' must parse >> as a valid uuid, but is otherwise ignored. The current qemu.git code >> base _only_ sets smbios uuid from the '-uuid uuid' argument. I've >> filed a bug against the qemu folks asking whether this is intended (in >> which case we have to modify libvirt to change the -uuid argument it >> outputs when smbios is specified), or an oversight (hopefully the >> latter, since it's still nice to correlate >> /var/log/libvirt/qemu/....log with the XML uuid even when that differs >> from the smbios uuid presented to the guest.) > > Hmm, I thought the UUID we were passing in was a host UUID, but > on closer inspection the type=1 table is definitely intended to > carry the guest UUID. As such it doesn't make sense to populate > that with anything other than the '<uuid>' from the guest XML. > A host UUID should live elsewhere in the SMBIOS tables, likely > in the type2 or type3 blocks What does that mean to our XML? Should we reject XML files where both domain/uuid and domain/sysinfo/system/entry/uuid exist, but differ? Both elements are optional, so it's feasible to see a guest uuid in either location. Meanwhile, I'm waiting on resolution to https://bugzilla.redhat.com/show_bug.cgi?id=659122 to see if qemu will be patched to let us stick the host's uuid in block 2 (base board) or block 3 (chassis), in which case, we'll need to expand our XML to support that notion.

I've also discovered that with current qemu, if both '-uuid uuid' and '-smbios type=1,uuid=uuid' are specified, then -uuid takes precedence; but either one of the two in isolation serves to set smbios block 1 with the guest's uuid.