kvm: x86: Add AMD's EX_CFG to the list of ignored MSRs

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".

Cc: stable@vger.kernel.org
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 62c62d3eb0ff89633633705d4529bc9b4500c90a..fed3636dce9a9d066ddecc05bcadae8f22e3cc3e 100644 (file)
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -372,6 +372,7 @@
 #define MSR_F15H_NB_PERF_CTR           0xc0010241
 #define MSR_F15H_PTSC                  0xc0010280
 #define MSR_F15H_IC_CFG                        0xc0011021
+#define MSR_F15H_EX_CFG                        0xc001102c
 
 /* Fam 10h MSRs */
 #define MSR_FAM10H_MMIO_CONF_BASE      0xc0010058

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f24329659bea888ca23333b8d6704fca3cfb10bc..ac431fa778aa4e461d3fa9d4b4e806fd84a0ddc0 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2227,6 +2227,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
        case MSR_AMD64_PATCH_LOADER:
        case MSR_AMD64_BU_CFG2:
        case MSR_AMD64_DC_CFG:
+       case MSR_F15H_EX_CFG:
                break;
 
        case MSR_IA32_UCODE_REV:
@@ -2508,6 +2509,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
        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_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3: