Merge tag 'fbdev-v4.13-rc5' of git://github.com/bzolnier/linux

[karo-tx-linux.git] / arch / x86 / kvm / svm.c

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 4d8141e533c369711df245d0a783683598ad4559..1107626938ccff4f26da130f8b570928ca7c8efb 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2430,6 +2430,16 @@ static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr,
        svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
        svm->vmcb->control.exit_code_hi = 0;
        svm->vmcb->control.exit_info_1 = error_code;
+
+       /*
+        * FIXME: we should not write CR2 when L1 intercepts an L2 #PF exception.
+        * The fix is to add the ancillary datum (CR2 or DR6) to structs
+        * kvm_queued_exception and kvm_vcpu_events, so that CR2 and DR6 can be
+        * written only when inject_pending_event runs (DR6 would written here
+        * too).  This should be conditional on a new capability---if the
+        * capability is disabled, kvm_multiple_exception would write the
+        * ancillary information to CR2 or DR6, for backwards ABI-compatibility.
+        */
        if (svm->vcpu.arch.exception.nested_apf)
                svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token;
        else