KVM: Ignore PCI ECS I/O enablement

Linux guests will try to enable access to the extended PCI config space
via the I/O ports 0xCF8/0xCFC on AMD Fam10h CPU. Since we (currently?)
don't use ECS, simply ignore write and read attempts.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 96f0ae7d97b6..af40e23df251 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -844,6 +844,8 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
                         return 1;
                 }
                 break;
+        case MSR_AMD64_NB_CFG:
+                break;
         case MSR_IA32_DEBUGCTLMSR:
                 if (!data) {
                         /* We support the non-activated case already */
@@ -1049,6 +1051,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
         case MSR_P6_EVNTSEL1:
         case MSR_K7_EVNTSEL0:
         case MSR_K8_INT_PENDING_MSG:
+        case MSR_AMD64_NB_CFG:
                 data = 0;
                 break;
         case MSR_MTRRcap: