Re: [BUG] sched/cache: "Make LLC id continuous" causes NULL cpumask dereference in build_sched_domains on POWER9

From: Srikar Dronamraju

Date: Thu May 28 2026 - 12:16:23 EST


* Shrikanth Hegde <sshegde@xxxxxxxxxxxxx> [2026-05-27 12:35:20]:

> On 5/26/26 10:54 AM, Venkat Rao Bagalkote wrote:
> >
> > On 26/05/26 9:38 am, Chen, Yu C wrote:
> > > Hi Venkat,
> > >
> > > On 5/26/2026 11:14 AM, Srikar Dronamraju wrote:
> > > > * Chen, Yu C <yu.c.chen@xxxxxxxxx> [2026-05-25 23:35:45]:
> > > >
> > > > > Hi Venkat,
> > > > >
> > > > > On 5/25/2026 10:07 PM, Venkat Rao Bagalkote wrote:
> > > > > > Greetings!!!
> > > > > >
> > > > > > I am seeing an early boot kernel panic due to NULL pointer dereference
> > > > > > on a POWER9 (pSeries) system when testing linux-next (next-20260522).
> >
> >
> > This issue is seen on P11 as well.
> >
> >
> > Regards,
> >
> > Venkat.
> >
>
> Venkat,
>
> Was it on P11 on Shared LPAR?

I also thought the same.
But I checked with Venkat, he said it was on a dedicated LPAR.
My multiple tries on dedicated, didnt reproduce the problem.

--
Thanks and Regards
Srikar Dronamraju