On 23/11/2016 23:07, David Matlack wrote: > A downside of this scheme is we'd have to remember to update > nested_vmx_cr4_fixed1_update() before giving VMs new CPUID bits. If we > forget, a VM could end up with different values for CR{0,4}_FIXED0 for > the same CPUID depending on which version of KVM you're running on. If userspace doesn't obey KVM_GET_SUPPORTED_CPUID, all bets are off anyway, so I don't think it's a big deal. However, if you want to make it generated by userspace, that would be fine as well! That would simply entail removing this patch, wouldn't it? Paolo > Hm, now I'm thinking you were right in the beginning. Userspace should > generate CR{0,4}_FIXED1, not the kernel. And KVM should allow > userspace to save/restore them. -- 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