fix MMIO_CONF_BASE MSR access

Commit Message

Andre Przywara July 2, 2009, 1:04 p.m. UTC

Some Windows versions check whether the BIOS has setup MMI/O for
 config space accesses on AMD Fam10h CPUs, we say "no" by returning 0 on
 reads and only allow disabling of MMI/O CfgSpace setup by igoring "0" writes.

Signed-off-by: Andre Przywara <[e-mail]>
---
 arch/x86/kvm/x86.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

This obsoletes the patch: "fix AMD Fam10h unhandled MSRs" from yesterday,
since part of it has already been applied with an older patch. This
contains only the remaining part.

Thanks and Regards,
Andre.

Comments

Avi Kivity July 7, 2009, 11:13 a.m. UTC | #1

On 07/02/2009 04:04 PM, Andre Przywara wrote:
>   Some Windows versions check whether the BIOS has setup MMI/O for
>   config space accesses on AMD Fam10h CPUs, we say "no" by returning 0 on
>   reads and only allow disabling of MMI/O CfgSpace setup by igoring "0" writes.
>    

Applied, thanks.

Patch

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6263991..60b2527 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -846,6 +846,13 @@  int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 			return 1;
 		}
 		break;
+	case MSR_FAM10H_MMIO_CONF_BASE:
+		if (data != 0) {
+			pr_unimpl(vcpu, "unimplemented MMIO_CONF_BASE wrmsr: "
+				"0x%llx\n", data);
+			return 1;
+		}
+		break;
 	case MSR_AMD64_NB_CFG:
 		break;
 	case MSR_IA32_DEBUGCTLMSR:
@@ -1054,6 +1061,7 @@  int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
 	case MSR_K7_EVNTSEL0:
 	case MSR_K8_INT_PENDING_MSG:
 	case MSR_AMD64_NB_CFG:
+	case MSR_FAM10H_MMIO_CONF_BASE:
 		data = 0;
 		break;
 	case MSR_MTRRcap: