On 20.12.2009, at 17:56, Michael S. Tsirkin wrote: > On Sun, Dec 20, 2009 at 05:59:33PM +0200, Avi Kivity wrote: >> On 12/20/2009 05:51 PM, Michael S. Tsirkin wrote: >>> >>>> Maybe we should make -cpu host the default. That will give the best >>>> performance for casual users, more testing for newer features, and will >>>> force management apps to treat migration much more seriously. The >>>> downside is that casual users upgrading their machines might experience >>>> issues with Windows. Feature compatibility is not just about migration. >>>> >>> This seems very aggressive. Can't we whitelist features that we know >>> about? Further, doesn't KVM already do this? >>> >>> >> >> It does, but without -cpuid host you're stuck with qemu64 (kvm.ko >> doesn't add features userspace didn't request). > > Hmm, then, shouldn't either kvm or qemu mask features that we do not > emulate well enough to make windows not crash?
-cpu host does that already, no? Alex
