On Tue, Apr 17, 2018 at 07:17:51PM +0200, Greg Kurz wrote: > Cc'ing David who should always be in the recipient list when posting ppc > related > patches :) > > On Tue, 17 Apr 2018 12:21:35 -0400 > Serhii Popovych <spopo...@redhat.com> wrote: > > > In non-NUMA configurations nb_numa_nodes is zero and we set 5th cell > > in ibm,max-associativity-domains to -1. That causes to stall Linux > > guests during boot after following line: > > > > [ 0.000000] NUMA associativity depth for CPU/Memory: 4 > > > > Make last possible NUMA in property zero to correct support for > > non-NUMA guests. > > > > Alternatively, as suggested by David in some other mail, you could drop the > property in this case. I've checked it fixes the hang too, and it probably > makes more sense than exposing only zeroes.
Actually, I think this is the better solution. qemu treats "not NUMA"
and "exactly one NUMA node" differently for historical reasons, but I
don't think that actually makes a whole lot of sense. I think
advertising them identically so we don't generate more special cases
on the guest side is a better idea.
> > Fixes: c1df49a670ef ("spapr: Add ibm,max-associativity-domains property")
>
> Since c1df49a670ef hasn't hit master yet, I guess we should squash this
> patch (or any alternative) there to preserve bisect, ie, either David
> does it for you or you post a v4 of your previous series.
Right, I've folded these together in my tree so we don't get an
interval of broken commits.
>
> > Signed-off-by: Serhii Popovych <spopo...@redhat.com>
> > ---
> > hw/ppc/spapr.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index 7b2bc4e..bff2125 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -914,7 +914,7 @@ static void spapr_dt_rtas(sPAPRMachineState *spapr,
> > void *fdt)
> > cpu_to_be32(0),
> > cpu_to_be32(0),
> > cpu_to_be32(0),
> > - cpu_to_be32(nb_numa_nodes - 1),
> > + cpu_to_be32(nb_numa_nodes ? nb_numa_nodes - 1 : 0),
> > };
> >
> > _FDT(rtas = fdt_add_subnode(fdt, 0, "rtas"));
>
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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