summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorHuaitong Han <huaitong.han@intel.com>2016-03-22 16:51:15 +0800
committerPaolo Bonzini <pbonzini@redhat.com>2016-03-22 16:21:04 +0100
commitddba262891494c1337fcbec8910605285012c121 (patch)
treee8dd487cfed4cfbb21548678ce2fd2d9c211b429 /arch
parente0b18ef7189075676ac432954d7920eaa30d8e3e (diff)
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')
-rw-r--r--arch/x86/kvm/vmx.c16
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);