diff options
| author | Huaitong Han | 2016-03-22 09:51:15 +0100 |
|---|---|---|
| committer | Paolo Bonzini | 2016-03-22 16:21:04 +0100 |
| commit | ddba262891494c1337fcbec8910605285012c121 (patch) | |
| tree | e8dd487cfed4cfbb21548678ce2fd2d9c211b429 /arch/x86/kvm/vmx.c | |
| parent | KVM: x86: remove magic number with enum cpuid_leafs (diff) | |
| download | kernel-qcow2-linux-ddba262891494c1337fcbec8910605285012c121.tar.gz kernel-qcow2-linux-ddba262891494c1337fcbec8910605285012c121.tar.xz kernel-qcow2-linux-ddba262891494c1337fcbec8910605285012c121.zip | |
KVM, pkeys: disable pkeys for guests in non-paging mode
Pkeys is disabled if CPU is in non-paging mode in hardware. However KVM
always uses paging mode to emulate guest non-paging, mode with TDP. To
emulate this behavior, pkeys needs to be manually disabled when guest
switches to non-paging mode.
Signed-off-by: Huaitong Han <huaitong.han@intel.com>
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 161230016dfa..1b8a41f64d35 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3893,13 +3893,17 @@ static int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) if (!enable_unrestricted_guest && !is_paging(vcpu)) /* - * SMEP/SMAP is disabled if CPU is in non-paging mode in - * hardware. However KVM always uses paging mode without - * unrestricted guest. - * To emulate this behavior, SMEP/SMAP needs to be manually - * disabled when guest switches to non-paging mode. + * SMEP/SMAP/PKU is disabled if CPU is in non-paging mode in + * hardware. To emulate this behavior, SMEP/SMAP/PKU needs + * to be manually disabled when guest switches to non-paging + * mode. + * + * If !enable_unrestricted_guest, the CPU is always running + * with CR0.PG=1 and CR4 needs to be modified. + * If enable_unrestricted_guest, the CPU automatically + * disables SMEP/SMAP/PKU when the guest sets CR0.PG=0. */ - hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP); + hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE); vmcs_writel(CR4_READ_SHADOW, cr4); vmcs_writel(GUEST_CR4, hw_cr4); |