kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS

commit 691bd4340bef49cf7e5855d06cf24444b5bf2d85 upstream.

It's easier for host applications, such as QEMU, if they can always
access guest MSR_IA32_BNDCFGS in VMCS, even though MPX is disabled in
guest cpuid.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Haozhong Zhang 2017-07-04 10:27:41 +08:00 committed by Greg Kroah-Hartman
parent 07592d6225
commit cce8d2ee45

View File

@ -2987,7 +2987,8 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = vmcs_readl(GUEST_SYSENTER_ESP);
break;
case MSR_IA32_BNDCFGS:
if (!kvm_mpx_supported() || !guest_cpuid_has_mpx(vcpu))
if (!kvm_mpx_supported() ||
(!msr_info->host_initiated && !guest_cpuid_has_mpx(vcpu)))
return 1;
msr_info->data = vmcs_read64(GUEST_BNDCFGS);
break;
@ -3069,7 +3070,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
vmcs_writel(GUEST_SYSENTER_ESP, data);
break;
case MSR_IA32_BNDCFGS:
if (!kvm_mpx_supported() || !guest_cpuid_has_mpx(vcpu))
if (!kvm_mpx_supported() ||
(!msr_info->host_initiated && !guest_cpuid_has_mpx(vcpu)))
return 1;
if (is_noncanonical_address(data & PAGE_MASK) ||
(data & MSR_IA32_BNDCFGS_RSVD))