Hi,
> > + if ((lpc->smi_host_features &
> > BIT_ULL(ICH9_LPC_SMI_F_CPU_HOT_UNPLUG_BIT)) &&
> > + !(lpc->smi_host_features &
> > BIT_ULL(ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT))) {
> > + /*
> > + * smi_features_ok_callback() throws an error on this.
> > + *
> > + * So bail out here instead of advertizing the invalid
> > + * configuration and get obscure firmware failures from that.
> > + */
> > + error_setg(errp, "cpu hot-unplug requires cpu hot-plug");
> > + return;
> > + }
>
> What does this actually mean in practice ? AFAIK from the libvirt side
> we don't do anything special to enable/disable CPU hotplug. What QEMU
> config setting is wrong to lead to this scenario, thta the user/mgmt
> app has to fix ?
It's ICH9-LPC.x-smi-cpu-{hotplug,hotunplug}. user/mgmt should not mess
with that, but given it is possible I think printing an error is better
than going for an assert().
If this triggers it is most likely qemu getting compat properties wrong.
Full story at https://bugzilla.redhat.com/show_bug.cgi?id=1985924 ;)
take care,
Gerd
