[PATCH 3.16 59/99] KVM: nVMX: vmread should not set rflags to specify success in case of #PF

[Ben Hutchings]

3.16.84-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Miaohe Lin <linmiaohe@xxxxxxxxxx>

commit a4d956b9390418623ae5d07933e2679c68b6f83c upstream.

In case writing to vmread destination operand result in a #PF, vmread
should not call nested_vmx_succeed() to set rflags to specify success.
Similar to as done in VMPTRST (See handle_vmptrst()).

Reviewed-by: Liran Alon <liran.alon@xxxxxxxxxx>
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 arch/x86/kvm/vmx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6455,8 +6455,10 @@ static int handle_vmread(struct kvm_vcpu
 		/* _system ok, as nested_vmx_check_permission verified cpl=0 */
 		if (kvm_write_guest_virt_system(vcpu, gva, &field_value,
 						(is_long_mode(vcpu) ? 8 : 4),
-						&e))
+						&e)) {
 			kvm_inject_page_fault(vcpu, &e);
+			return 1;
+		}
 	}
 
 	nested_vmx_succeed(vcpu);