kvm/x86: return meaningful value from KVM_SIGNAL_MSI

If kvm_apic_map_get_dest_lapic() finds a disabled LAPIC,
it will return with bitmap==0 and (*r == -1) will be returned to
userspace.

QEMU may then record "KVM: injection failed, MSI lost
(Operation not permitted)" in its log, which is quite puzzling.

Reported-by: Peng Hao <penghao122@sina.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2018-10-01 16:07:18 +02:00
parent 4fef0f4913
commit 0624fca951
1 changed files with 3 additions and 3 deletions

View File

@ -960,14 +960,14 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
map = rcu_dereference(kvm->arch.apic_map);
ret = kvm_apic_map_get_dest_lapic(kvm, &src, irq, map, &dst, &bitmap);
if (ret)
if (ret) {
*r = 0;
for_each_set_bit(i, &bitmap, 16) {
if (!dst[i])
continue;
if (*r < 0)
*r = 0;
*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
}
}
rcu_read_unlock();
return ret;