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
Attachment:
signature.asc
Description: OpenPGP digital signature
