On Sep 19, 2014 9:53 AM, "Gleb Natapov" <gleb@xxxxxxxxxx> wrote: > > On Fri, Sep 19, 2014 at 09:40:07AM -0700, H. Peter Anvin wrote: > > On 09/19/2014 09:37 AM, Gleb Natapov wrote: > > > > > > Linux detects what hypervior it runs on very early > > > > Not anywhere close to early enough. We're talking for uses like kASLR. > > > Still to early to do: > > h = cpuid(HYPERVIOR_SIGNATURE) > if (h == KVMKVMKVM) { > if (cpuid(kvm_features) & kvm_rnd) > rdmsr(kvm_rnd) > else (h == HyperV) { > if (cpuid(hv_features) & hv_rnd) > rdmsr(hv_rnd) > else (h == XenXenXen) { > if (cpuid(xen_features) & xen_rnd) > rdmsr(xen_rnd) > } > I think that there's a lot of value in having each guest implementation be automatically compatible with all hypervisors. For example, you forgot VMware, and VMware might be less excited about implementing this feature if all the guests won't immediately start using it. > ? > > -- > Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html