| From 61cb57c9ed631c95b54f8e9090c89d18b3695b3c Mon Sep 17 00:00:00 2001 |
| From: Liran Alon <liran.alon@oracle.com> |
| Date: Sun, 5 Nov 2017 16:56:32 +0200 |
| Subject: KVM: x86: Exit to user-mode on #UD intercept when emulator requires |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Liran Alon <liran.alon@oracle.com> |
| |
| commit 61cb57c9ed631c95b54f8e9090c89d18b3695b3c upstream. |
| |
| Instruction emulation after trapping a #UD exception can result in an |
| MMIO access, for example when emulating a MOVBE on a processor that |
| doesn't support the instruction. In this case, the #UD vmexit handler |
| must exit to user mode, but there wasn't any code to do so. Add it for |
| both VMX and SVM. |
| |
| Signed-off-by: Liran Alon <liran.alon@oracle.com> |
| Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com> |
| Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
| Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
| Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com> |
| Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> |
| Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/kvm/svm.c | 2 ++ |
| arch/x86/kvm/vmx.c | 2 ++ |
| 2 files changed, 4 insertions(+) |
| |
| --- a/arch/x86/kvm/svm.c |
| +++ b/arch/x86/kvm/svm.c |
| @@ -1696,6 +1696,8 @@ static int ud_interception(struct vcpu_s |
| int er; |
| |
| er = emulate_instruction(&svm->vcpu, EMULTYPE_TRAP_UD); |
| + if (er == EMULATE_USER_EXIT) |
| + return 0; |
| if (er != EMULATE_DONE) |
| kvm_queue_exception(&svm->vcpu, UD_VECTOR); |
| return 1; |
| --- a/arch/x86/kvm/vmx.c |
| +++ b/arch/x86/kvm/vmx.c |
| @@ -5267,6 +5267,8 @@ static int handle_exception(struct kvm_v |
| return 1; |
| } |
| er = emulate_instruction(vcpu, EMULTYPE_TRAP_UD); |
| + if (er == EMULATE_USER_EXIT) |
| + return 0; |
| if (er != EMULATE_DONE) |
| kvm_queue_exception(vcpu, UD_VECTOR); |
| return 1; |
