diff options
| -rw-r--r-- | arch/x86/include/asm/msr-index.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 19 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 823d48223400..fd5a1f365c95 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -43,6 +43,7 @@ #define MSR_MTRRcap 0x000000fe #define MSR_IA32_BBL_CR_CTL 0x00000119 +#define MSR_IA32_BBL_CR_CTL3 0x0000011e #define MSR_IA32_SYSENTER_CS 0x00000174 #define MSR_IA32_SYSENTER_ESP 0x00000175 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a7f65aa6eef6..7faf262ab202 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1592,6 +1592,12 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) } else return set_msr_hyperv(vcpu, msr, data); break; + case MSR_IA32_BBL_CR_CTL3: + /* Drop writes to this legacy MSR -- see rdmsr + * counterpart for further detail. + */ + pr_unimpl(vcpu, "ignored wrmsr: 0x%x data %llx\n", msr, data); + break; default: if (msr && (msr == vcpu->kvm->arch.xen_hvm_config.msr)) return xen_hvm_config(vcpu, data); @@ -1846,6 +1852,19 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) } else return get_msr_hyperv(vcpu, msr, pdata); break; + case MSR_IA32_BBL_CR_CTL3: + /* This legacy MSR exists but isn't fully documented in current + * silicon. It is however accessed by winxp in very narrow + * scenarios where it sets bit #19, itself documented as + * a "reserved" bit. Best effort attempt to source coherent + * read data here should the balance of the register be + * interpreted by the guest: + * + * L2 cache control register 3: 64GB range, 256KB size, + * enabled, latency 0x1, configured + */ + data = 0xbe702111; + break; default: if (!ignore_msrs) { pr_unimpl(vcpu, "unhandled rdmsr: 0x%x\n", msr); |