diff options
| author | Jes Sorensen | 2010-09-09 12:06:46 +0200 |
|---|---|---|
| committer | Avi Kivity | 2010-10-24 10:52:27 +0200 |
| commit | 7b91409822ed37f2a58974e49498bdbe92ddd93c (patch) | |
| tree | 82b049d7840556e576dd33409ae2499c25bd9074 /arch | |
| parent | b9a52c4b78ec254ee00cce47d75efd89b09f13dd (diff) | |
KVM: x86: Emulate MSR_EBC_FREQUENCY_ID
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@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | 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 f47db2588a41..9d434777154d 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; |