From e1e746b3c55d1d1e0841a2e600a154d8f6747232 Mon Sep 17 00:00:00 2001 From: Feng Wu Date: Tue, 1 Apr 2014 17:46:35 +0800 Subject: [PATCH] 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 Signed-off-by: Marcelo Tosatti --- 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 1320e0f8e611..1f68c5831924 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3484,13 +3484,14 @@ 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; } -- GitLab