On Sun, Dec 01, 2024 at 07:49:44PM +0000, Marc Zyngier wrote:
> Hi Mike,
>
> On Sun, 01 Dec 2024 19:32:22 +0000,
> Mike Rapoport <rppt@xxxxxxxxxx> wrote:
> >
> > Hi Marc,
> >
> > On Sun, Dec 01, 2024 at 09:27:02AM +0000, Marc Zyngier wrote:
> > > Commit 767507654c22 ("arch_numa: switch over to numa_memblks")
> > > significantly cleaned up the NUMA registration code, but also
> > > dropped a significant check that was refusing to accept to
> > > configure a memblock with an invalid nid.
> >
> > ...
> >
> > > while previous kernel versions were able to recognise how brain-damaged
> > > the machine is, and only build a fake node.
> > >
> > > Use the memblock_validate_numa_coverage() helper to restore some sanity
> > > and a "working" system.
> > >
> > > Fixes: 767507654c22 ("arch_numa: switch over to numa_memblks")
> > > Suggested-by: Mike Rapoport <rppt@xxxxxxxxxx>
> > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
> > > Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> > > Cc: Will Deacon <will@xxxxxxxxxx>
> > > Cc: Zi Yan <ziy@xxxxxxxxxx>
> > > Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> > > Cc: David Hildenbrand <david@xxxxxxxxxx>
> > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > ---
> > > drivers/base/arch_numa.c | 4 ++++
> > > 1 file changed, 4 insertions(+)
> > >
> > > diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
> > > index e187016764265..c63a72a1fed64 100644
> > > --- a/drivers/base/arch_numa.c
> > > +++ b/drivers/base/arch_numa.c
> > > @@ -208,6 +208,10 @@ static int __init numa_register_nodes(void)
> > > {
> > > int nid;
> > >
> > > + /* Check the validity of the memblock/node mapping */
> > > + if (!memblock_validate_numa_coverage(1))
> >
> > I've changed this to memblock_validate_numa_coverage(0) and applied along
> > with my patch that changed memblock_validate_numa_coverage() to work with
> > 0:
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock.git/log/?h=thunderx-fix
> >
> > Can you please verify that it works on your "quality hardware"?
>
> Commit 427c6179e159b in your tree still has memblock_validate_numa_coverage(1).
> Forgot to push out the updated version?
Argh, indeed.
> Flipping this to 0 locally, I have verified that this still allows the
> old thing to trudge along:
>
> root@duodenum:~# uname -a
> Linux duodenum 6.12.0-12115-g427c6179e159-dirty #3896 SMP PREEMPT Sun Dec 1 19:43:13 GMT 2024 aarch64
Thanks for testing!
> Thanks again,
>
> M.
--
Sincerely yours,
Mike.
