KVM: x86: report negative values from wrmsr emulation to userspace

This will allow the KVM to report such errors (e.g -ENOMEM)
to the userspace.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20201001112954.6258-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Maxim Levitsky 2020-10-01 14:29:52 +03:00 committed by Paolo Bonzini
parent 36385ccc9b
commit 7dffecaf4e
2 changed files with 8 additions and 5 deletions

View File

@ -3712,10 +3712,10 @@ static int em_wrmsr(struct x86_emulate_ctxt *ctxt)
if (r == X86EMUL_IO_NEEDED)
return r;
if (r)
if (r > 0)
return emulate_gp(ctxt, 0);
return X86EMUL_CONTINUE;
return r < 0 ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE;
}
static int em_rdmsr(struct x86_emulate_ctxt *ctxt)

View File

@ -1737,13 +1737,16 @@ int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu)
r = kvm_set_msr(vcpu, ecx, data);
/* MSR write failed? See if we should ask user space */
if (r && kvm_set_msr_user_space(vcpu, ecx, data, r)) {
if (r && kvm_set_msr_user_space(vcpu, ecx, data, r))
/* Bounce to user space */
return 0;
}
/* Signal all other negative errors to userspace */
if (r < 0)
return r;
/* MSR write failed? Inject a #GP */
if (r) {
if (r > 0) {
trace_kvm_msr_write_ex(ecx, data);
kvm_inject_gp(vcpu, 0);
return 1;