[PATCH 2/3] KVM: Fix mov cr4 #GP at wrong instruction

Avi Kivity
2010-06-10T14:02:20Z

arch/x86/kvm/vmx.c | 4 ++--
arch/x86/kvm/x86.c | 10 ++--------
3 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f0683c8..f52196d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -598,7 +598,7 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,

int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3);
-void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
+int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
void kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8);
int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val);
int kvm_get_dr(struct kvm_vcpu *vcpu, int dr, unsigned long *val);
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index a6a5121..9d083e9 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3190,8 +3190,8 @@ static int handle_cr(struct kvm_vcpu *vcpu)
skip_emulated_instruction(vcpu);
return 1;
case 4:
- kvm_set_cr4(vcpu, val);
- skip_emulated_instruction(vcpu);
+ err = kvm_set_cr4(vcpu, val);
+ complete_insn_gp(vcpu, err);
return 1;
case 8: {
u8 cr8_prev = kvm_get_cr8(vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 72df8fd..60b5154 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -468,7 +468,7 @@ void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
}
EXPORT_SYMBOL_GPL(kvm_lmsw);

-int __kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
+int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
unsigned long old_cr4 = kvm_read_cr4(vcpu);
unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE;
@@ -494,12 +494,6 @@ int __kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)

return 0;
}
-
-void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
-{
- if (__kvm_set_cr4(vcpu, cr4))
- kvm_inject_gp(vcpu, 0);
-}
EXPORT_SYMBOL_GPL(kvm_set_cr4);

static int __kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
@@ -3655,7 +3649,7 @@ static int emulator_set_cr(int cr, unsigned long val, struct kvm_vcpu *vcpu)
res = __kvm_set_cr3(vcpu, val);
break;
case 4:
- res = __kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
+ res = kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
break;
case 8:
res = __kvm_set_cr8(vcpu, val & 0xfUL);
--
1.7.1