But will the difference between the vendor ID and family number cause confusion to the OS in VM? On Sat, May 4, 2013 at 4:05 PM, Jan Kiszka <jan.kiszka@xxxxxx> wrote: > On 2013-05-04 09:50, 李春奇 <Arthur Chunqi Li> wrote: >> Hi Jan and All, >> I find that when enable KVM with qemu, vendor ID of simulated CPU will be >> set the same as host, but other features such as level, family, model, >> stepping are not changed. This may bring out a confusing result, the >> simulated CPU has a vendor name of "GenuineIntel" but with family number >> "16". >> >> I disabled the related code in function cpu_x86_find_by_name: >> diff --git a/target-i386/cpu.c b/target-i386/cpu.c >> index e2302d8..df0e82e 100644 >> --- a/target-i386/cpu.c >> +++ b/target-i386/cpu.c >> @@ -1295,7 +1295,8 @@ static int cpu_x86_find_by_name(x86_def_t >> *x86_cpu_def, const char *name) >> * KVM's sysenter/syscall emulation in compatibility mode and >> * when doing cross vendor migration >> */ >> - if (kvm_enabled()) { >> + //if (kvm_enabled()) { >> + if (0) { >> uint32_t ebx = 0, ecx = 0, edx = 0; >> host_cpuid(0, 0, NULL, &ebx, &ecx, &edx); >> x86_cpu_vendor_words2str(x86_cpu_def->vendor, ebx, edx, >> ecx); >> >> And the information of CPU remains consistent and the VM runs OK, even >> though with nested environment. >> >> Why should qemu set simulated cpu's vendor same as the host in KVM >> environment? > > The reason (and a way out) is given in the comment above the cited code. > > Jan > > -- Arthur Chunqi Li Department of Computer Science School of EECS Peking University Beijing, China -- 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