On Wed, Aug 01, 2012, Avi Kivity wrote about "Re: Nested kvm_intel broken on pre 3.3 hosts": > Right - it's not just kvm-as-a-guest that will trip on this. But > there's no point in everyone backporting it on their own. If you're > doing the backport, please post it here and we'll forward it to the > stable branch. If I understand correctly, the failure occurs because new versions of KVM refuse to work if the processor doesn't support CPU_BASED_RDPMC_EXITING - which older versions of nested VMX didn't say that they did. But must the KVM guest refuse to work if this feature isn't supported? I.e., why not move in setup_vmcs_config() the CPU_BASED_RDPMC_EXITING from "min" to "opt"? Isn't losing the PMU feature a lesser evil than not working at all? In any case, perhaps the original reporter can use this as a workaround, at least, because it requires modifying the (L1) guest, not the host. -- Nadav Har'El | Wednesday, Aug 1 2012, 13 Av 5772 nyh@xxxxxxxxxxxxxxxxxxx |----------------------------------------- Phone +972-523-790466, ICQ 13349191 |May you live as long as you want - and http://nadav.harel.org.il |never want as long as you live. -- 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
