KVM: Activate fpu on clts
Assume that if the guest executes clts, it knows what it's doing, and load the
guest fpu to prevent an #NM exception.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a281368..800208a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1259,12 +1259,17 @@
return 1;
}
-static int nm_interception(struct vcpu_svm *svm)
+static void svm_fpu_activate(struct kvm_vcpu *vcpu)
{
+ struct vcpu_svm *svm = to_svm(vcpu);
svm->vmcb->control.intercept_exceptions &= ~(1 << NM_VECTOR);
svm->vcpu.fpu_active = 1;
update_cr0_intercept(svm);
+}
+static int nm_interception(struct vcpu_svm *svm)
+{
+ svm_fpu_activate(&svm->vcpu);
return 1;
}
@@ -2977,6 +2982,7 @@
.cache_reg = svm_cache_reg,
.get_rflags = svm_get_rflags,
.set_rflags = svm_set_rflags,
+ .fpu_activate = svm_fpu_activate,
.fpu_deactivate = svm_fpu_deactivate,
.tlb_flush = svm_flush_tlb,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index b7e812e..fad871c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3002,6 +3002,7 @@
vmx_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
trace_kvm_cr_write(0, kvm_read_cr0(vcpu));
skip_emulated_instruction(vcpu);
+ vmx_fpu_activate(vcpu);
return 1;
case 1: /*mov from cr*/
switch (cr) {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c61ec9c..4db0c8a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3269,6 +3269,7 @@
int emulate_clts(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));
+ kvm_x86_ops->fpu_activate(vcpu);
return X86EMUL_CONTINUE;
}