| Message ID | 20170704022741.23869-1-haozhong.zhang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/07/2017 04:27, Haozhong Zhang wrote: > It's free for host applications, such as QEMU, to access guest > MSR_IA32_BNDCFGS in VMCS, even though MPX is disabled in guest cpuid. > > Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> Thanks, committed to kvm.git with Cc: stable@vger.kernel.org Paolo > --- > arch/x86/kvm/vmx.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index fb0471268a14..b4cfdcfdc1c1 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -3196,7 +3196,8 @@ 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; > @@ -3278,7 +3279,8 @@ 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)) >
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index fb0471268a14..b4cfdcfdc1c1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3196,7 +3196,8 @@ 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; @@ -3278,7 +3279,8 @@ 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))
It's free for host applications, such as QEMU, to access guest MSR_IA32_BNDCFGS in VMCS, even though MPX is disabled in guest cpuid. Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> --- arch/x86/kvm/vmx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)