On Tue, Jan 21, 2014 at 05:13:50PM +0100, Paolo Bonzini wrote: > Il 21/01/2014 16:51, Andreas Färber ha scritto: > >>> We already do that for other bits (e.g. XSAVE/OSXSAVE), > >Please point me to the commit, a search for xsave did not come up with a > >commit changing such a thing - either it did not go through my queue or > >it slipped me through: Bugs are no excuse to produce more bugs. > > I meant that "-cpu SandyBridge" with TCG produces a CPU that doesn't > have XSAVE. > > >>> and in fact it > >>> is the same that we do for KVM: the KVM_GET_SUPPORTED_CPUID result is > >>> used to trim the generic feature bits. > >Our model definitions are the place to put stuff that real CPUs have. > >Either the CPU has it or it doesn't. If it does, then this patch is > >fully correct and it's TCG's job to mask things out. If we're adding > >artificial flags to the generic model definitions just to make KVM > >faster, then it is wrong - we have a choice of post_initialize and > >realize hooks for that. > > It would make TCG faster as well, and there would be no reason > really to avoid the "artificial" x2apic on TCG, if TCG implemented > x2apic at all.
So, the discussion seem to have stalled. Andreas, are you still against the patch, after the arguments from Paolo and me? -- Eduardo
