On Mon, Jan 21, 2019 at 04:28:53PM -0800, Mike Larkin wrote:
> On Mon, Jan 21, 2019 at 09:27:59PM +0100, [email protected] wrote:
> > >Synopsis: if hw.smt=0 hw.ncpuonline=1 even if hw.ncpufound=2
> > >Category: kernel
> > >Environment:
> > System : OpenBSD 6.4
> > Details : OpenBSD 6.4 (GENERIC.MP) #3: Thu Dec 20 19:19:32 CET 2018
> >
> > [email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> >
> > Architecture: OpenBSD.amd64
> > Machine : amd64
> > >Description:
> > On Vsphere 6.0 an OpenBSD guest does recognizes the second cpu but it
> > cannot put it online
> > The host uses an AMD cpu
> > >How-To-Repeat:
> > Start a vm on Vsphere 6.0 with smt disabled
> > >Fix:
> > setting hw.smt=1 is a workaround, a reboot is not needed
> >
> >
>
> Looks like the hypervisor is presenting us with a topology of 1 core 2
> threads.
>
> We don't enable smt by default anymore. Search the lists and you'll find out
> why.
>
> -ml
>
I am aware of the reason why smt is disabled by default, this was more a
warning for users then
a real bug report, it just surprised me that the second cpu was not online even
with GENERIC.MP.
Giovanni
