3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eduardo Habkost <ehabkost@xxxxxxxxxx> commit 0e1b869fff60c81b510c2d00602d778f8f59dd9a upstream. Some guests OSes (including Windows 10) write to MSR 0xc001102c on some cases (possibly while trying to apply a CPU errata). Make KVM ignore reads and writes to that MSR, so the guest won't crash. The MSR is documented as "Execution Unit Configuration (EX_CFG)", at AMD's "BIOS and Kernel Developer's Guide (BKDG) for AMD Family 15h Models 00h-0Fh Processors". Signed-off-by: Eduardo Habkost <ehabkost@xxxxxxxxxx> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/x86/include/uapi/asm/msr-index.h | 1 + arch/x86/kvm/x86.c | 2 ++ 2 files changed, 3 insertions(+) --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -236,6 +236,7 @@ #define MSR_F15H_PERF_CTR 0xc0010201 #define MSR_F15H_NB_PERF_CTL 0xc0010240 #define MSR_F15H_NB_PERF_CTR 0xc0010241 +#define MSR_F15H_EX_CFG 0xc001102c /* Fam 10h MSRs */ #define MSR_FAM10H_MMIO_CONF_BASE 0xc0010058 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2086,6 +2086,7 @@ int kvm_set_msr_common(struct kvm_vcpu * case MSR_AMD64_PATCH_LOADER: case MSR_AMD64_BU_CFG2: case MSR_AMD64_DC_CFG: + case MSR_F15H_EX_CFG: break; case MSR_EFER: @@ -2464,6 +2465,7 @@ int kvm_get_msr_common(struct kvm_vcpu * case MSR_AMD64_BU_CFG2: case MSR_IA32_PERF_CTL: case MSR_AMD64_DC_CFG: + case MSR_F15H_EX_CFG: msr_info->data = 0; break; case MSR_P6_PERFCTR0:
