[PATCH 3/3] KVM: Fix mov cr3 #GP at wrong instruction

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

arch/x86/kvm/mmu.c | 2 +-
arch/x86/kvm/svm.c | 4 ++--
arch/x86/kvm/vmx.c | 4 ++--
arch/x86/kvm/x86.c | 10 ++--------
5 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f52196d..b127041 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -597,7 +597,7 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason,
bool has_error_code, u32 error_code);

int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
-void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3);
+int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3);
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);
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 75ddaa1..fcf5555 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3201,7 +3201,7 @@ static int kvm_pv_mmu_write(struct kvm_vcpu *vcpu,

static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu *vcpu)
{
- kvm_set_cr3(vcpu, vcpu->arch.cr3);
+ (void)kvm_set_cr3(vcpu, vcpu->arch.cr3);
return 1;
}

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 6d1616d..f7a6fdc 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1963,7 +1963,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm)
svm->vmcb->save.cr3 = hsave->save.cr3;
svm->vcpu.arch.cr3 = hsave->save.cr3;
} else {
- kvm_set_cr3(&svm->vcpu, hsave->save.cr3);
+ (void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3);
}
kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, hsave->save.rax);
kvm_register_write(&svm->vcpu, VCPU_REGS_RSP, hsave->save.rsp);
@@ -2086,7 +2086,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
svm->vmcb->save.cr3 = nested_vmcb->save.cr3;
svm->vcpu.arch.cr3 = nested_vmcb->save.cr3;
} else
- kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3);
+ (void)kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3);

/* Guest paging mode is active - reset mmu */
kvm_mmu_reset_context(&svm->vcpu);
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 9d083e9..f15f6bd 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3186,8 +3186,8 @@ static int handle_cr(struct kvm_vcpu *vcpu)
complete_insn_gp(vcpu, err);
return 1;
case 3:
- kvm_set_cr3(vcpu, val);
- skip_emulated_instruction(vcpu);
+ err = kvm_set_cr3(vcpu, val);
+ complete_insn_gp(vcpu, err);
return 1;
case 4:
err = kvm_set_cr4(vcpu, val);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 60b5154..b31d3fe 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -496,7 +496,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
}
EXPORT_SYMBOL_GPL(kvm_set_cr4);

-static int __kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
+int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
{
if (cr3 == vcpu->arch.cr3 && !pdptrs_changed(vcpu)) {
kvm_mmu_sync_roots(vcpu);
@@ -535,12 +535,6 @@ static int __kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
vcpu->arch.mmu.new_cr3(vcpu);
return 0;
}
-
-void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
-{
- if (__kvm_set_cr3(vcpu, cr3))
- kvm_inject_gp(vcpu, 0);
-}
EXPORT_SYMBOL_GPL(kvm_set_cr3);

int __kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8)
@@ -3646,7 +3640,7 @@ static int emulator_set_cr(int cr, unsigned long val, struct kvm_vcpu *vcpu)
vcpu->arch.cr2 = val;
break;
case 3:
- res = __kvm_set_cr3(vcpu, val);
+ res = kvm_set_cr3(vcpu, val);
break;
case 4:
res = kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
--
1.7.1