From: Jes Sorensen <Jes.Sorensen@xxxxxxxxxx> Some operating systems store data about the host processor at the time of installation, and when booted on a more uptodate cpu tries to read MSR_EBC_FREQUENCY_ID. This has been found with XP. Signed-off-by: Jes Sorensen <Jes.Sorensen@xxxxxxxxxx> --- arch/x86/kvm/x86.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f47db25..9d43477 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1651,6 +1651,20 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) case 0xcd: /* fsb frequency */ data = 3; break; + /* + * MSR_EBC_FREQUENCY_ID + * Conservative value valid for even the basic CPU models. + * Models 0,1: 000 in bits 23:21 indicating a bus speed of + * 100MHz, model 2 000 in bits 18:16 indicating 100MHz, + * and 266MHz for model 3, or 4. Set Core Clock + * Frequency to System Bus Frequency Ratio to 1 (bits + * 31:24) even though these are only valid for CPU + * models > 2, however guests may end up dividing or + * multiplying by zero otherwise. + */ + case MSR_EBC_FREQUENCY_ID: + data = 1 << 24; + break; case MSR_IA32_APICBASE: data = kvm_get_apic_base(vcpu); break; -- 1.7.1 -- 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
