3.13.11-ckt31 -stable review patch.  If anyone has any objections, please let 
me know.

------------------

From: Feng Wu <feng...@intel.com>

commit e1e746b3c55d1d1e0841a2e600a154d8f6747232 upstream.

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...@intel.com>
Signed-off-by: Marcelo Tosatti <mtosa...@redhat.com>
[ kamal: 3.13-stable prereq for
  656ec4a KVM: VMX: fix SMEP and SMAP without EPT ]
Signed-off-by: Kamal Mostafa <ka...@canonical.com>
---
 arch/x86/kvm/vmx.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 9c2c662..45019f0 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3429,13 +3429,14 @@ static int vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned 
long cr4)
                        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;
                }
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to