On 06/08/16 13:36, Paolo Bonzini wrote: > > > On 03/06/2016 08:09, Haozhong Zhang wrote: > > LMCE is disabled by default, but a cpu option 'lmce=on/off' is provided > > to enable/disable it. Migration is only allowed between VCPUs with the > > same lmce option. > > This is not needed at all if you do the change in patch 1 that Eduardo > requested (refuse to start if the host doesn't have the required > capabilities). > > So if you do that you can just move the lmce property to patch 1. >
But it doesn't cover the migration from lmce-enabled qemu to lmce-disabled qemu where KVM on both hosts support LMCE. In that case, both qemu can start without failure, but the guest OS will run in a VM with different configurations after migration. To avoid this, I didn't leave the lmce property in patch 1, so that users have no way to enable LMCE without this patch 2. Thanks, Haozhong
