KVM: x86: emulator: Return to user-mode on L1 CPL=0 emulation failure
authorLiran Alon <liran.alon@oracle.com>
Sun, 5 Nov 2017 14:56:33 +0000 (16:56 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 3 Feb 2018 16:38:55 +0000 (17:38 +0100)
[ Upstream commit 1f4dcb3b213235e642088709a1c54964d23365e9 ]

On this case, handle_emulation_failure() fills kvm_run with
internal-error information which it expects to be delivered
to user-mode for further processing.
However, the code reports a wrong return-value which makes KVM to never
return to user-mode on this scenario.

Fixes: 6d77dbfc88e3 ("KVM: inject #UD if instruction emulation fails and exit to
userspace")

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>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kvm/x86.c

index 575c8953cc9a3530bb596e60a6d09e49b38d5648..b25326ad82a13a3e49594a9040d410a4f82999e2 100644 (file)
@@ -5416,7 +5416,7 @@ static int handle_emulation_failure(struct kvm_vcpu *vcpu)
                vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
                vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
                vcpu->run->internal.ndata = 0;
-               r = EMULATE_FAIL;
+               r = EMULATE_USER_EXIT;
        }
        kvm_queue_exception(vcpu, UD_VECTOR);