Commit 61cb57c9 authored Nov 05, 2017 by Liran Alon Committed by Paolo Bonzini Nov 17, 2017

KVM: x86: Exit to user-mode on #UD intercept when emulator requires



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>
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

parent ac9b305c

arch/x86/kvm/svm.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -2204,6 +2204,8 @@ static int ud_interception(struct vcpu_svm *svm)

		WARN_ON_ONCE(is_guest_mode(&svm->vcpu));
		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;

arch/x86/kvm/vmx.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -5919,6 +5919,8 @@ static int handle_exception(struct kvm_vcpu *vcpu)
		if (is_invalid_opcode(intr_info)) {
		WARN_ON_ONCE(is_guest_mode(vcpu));
		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;