KVM: Disable SMAP for guests in EPT realmode and EPT unpaging mode
SMAP 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, SMAP needs to be
manually disabled when guest switches to non-paging mode.
Signed-off-by: Feng Wu <feng.wu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 1320e0f..1f68c58 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3484,13 +3484,14 @@
hw_cr4 &= ~X86_CR4_PAE;
hw_cr4 |= X86_CR4_PSE;
/*
- * SMEP is disabled if CPU is in non-paging mode in
- * hardware. However KVM always uses paging mode to
+ * SMEP/SMAP 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, SMEP needs to be manually
- * disabled when guest switches to non-paging mode.
+ * To emulate this behavior, SMEP/SMAP needs to be
+ * manually disabled when guest switches to non-paging
+ * mode.
*/
- hw_cr4 &= ~X86_CR4_SMEP;
+ hw_cr4 &= ~(X86_CR4_SMEP | X86_CR4_SMAP);
} else if (!(cr4 & X86_CR4_PAE)) {
hw_cr4 &= ~X86_CR4_PAE;
}