On Sun, Jan 15, 2012 at 08:44:50PM +0100, Stephan Bärwolf wrote: > Thank you for applying this, Marcelo. > > I fear we (or me after I agreed) did some mistake by erasing the additional > cpuid 0x80000001 checks. > In contradiction to only AMD it MUST also apply on Intel-CPUs. > > Documentation > "http://www.intel.com/content/dam/doc/manual/64-ia-32-architectures-software-developer-manual-325462.pdf"; > Vol. 2A 3-207 (PDF-page 811) first block of table. > (in addition AMD's doku > "http://support.amd.com/us/Processor_TechDocs/APM_V3_24594.pdf"; > page 376 (PDF-page 408) table "Exceptions" on the bottom) > > Not all CPUs might have a syscall op at all (even in longmode) - they > informing about that > via cpuid (But MSR_EFER may be still set). > (You can force it externally in qemu-kvm-emulation via "-cpu host,-syscall" > ...) > So an (guest) operating-system might not install *STAR-registers and crash > again on such vcpus, right?
No because if the operating system does not install the STAR MSRs, it will not set SCE bit in MSR_EFER (and your patch handles that situation). -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
