Re: [Qemu-devel] [PATCH] target-i386: Disable CPUID_EXT_MONITOR when KVM is enabled

[Eduardo Habkost]

On Sat, May 25, 2013 at 08:25:49AM +0200, Paolo Bonzini wrote:
> Il 25/05/2013 03:21, Bandan Das ha scritto:
> > There is one user-visible effect: "-cpu ...,enforce" will stop failing
> > because of missing KVM support for CPUID_EXT_MONITOR. But that's exactly
> > the point: there's no point in having CPU model definitions that would
> > never work as-is with neither TCG or KVM. This patch is changing the
> > meaning of (e.g.) "-machine ...,accel=kvm -cpu Opteron_G3" to match what
> > was already happening in practice.
> 
> But then -cpu Opteron_G3 does not match a "real" Opteron G3.  Is it
> worth it?

No models match a "real" CPU this way, because neither TCG or KVM
support all features supported by a real CPU. I ask the opposite
question: is it worth maintaining an "accurate" CPU model definition
that would never work without feature-bit tweaking in the command-line?

-- 
Eduardo