Re: [PATCH 1/9] mm: numa_memblks: set numa_nodes_parsed in numa_add_memblk()

[Mike Rapoport <rppt@kernel.org>]

On Thu, Jul 02, 2026 at 10:43:40PM +0900, Sang-Heon Jeon wrote:
> Hi, Mike
> 
> On Thu, Jul 2, 2026 at 7:38 PM Mike Rapoport <rppt@kernel.org> wrote:
> >
> > > Every existing numa_add_memblk() caller separately marks the new node in
> > > numa_nodes_parsed with node_set(). Set the node in numa_add_memblk() itself
> > > on a successful add, so this no longer depends on each caller.
> > >
> > > numa_add_memblk_to() now returns -EINVAL for an out-of-range node id, so a
> > > zero return implies @nid was valid. No existing caller passes an
> > > invalid one, so existing callers are unaffected.
> > >
> > > The per-caller node_set() calls are removed in later patches.
> > >
> > > Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
> > >
> > > diff --git a/mm/numa_memblks.c b/mm/numa_memblks.c
> > > index 3c3c4eac3514..2d92ca38c02a 100644
> > > --- a/mm/numa_memblks.c
> > > +++ b/mm/numa_memblks.c
> > > @@ -135,14 +135,17 @@ EXPORT_SYMBOL(__node_distance);
> > >  static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
> > >                                    struct numa_meminfo *mi)
> > >  {
> > > -     /* ignore zero length blks */
> > > -     if (start == end)
> > > -             return 0;
> > > -
> > >       /* whine about and ignore invalid blks */
> > > -     if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
> > > +     if (nid < 0 || nid >= MAX_NUMNODES) {
> > >               pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
> > >                       nid, start, end - 1);
> > > +             return -EINVAL;
> > > +     }
> > > +
> > > +     /* ignore zero length or invalid blks */
> > > +     if (start >= end) {
> > > +             pr_warn("Warning: invalid memblk node size %d [mem %#010Lx-%#010Lx]\n",
> > > +                     nid, start, end - 1);
> >
> > Nit: any reason to put this check here instead of replacing
> >
> >         if (start == end)
> >
> > ?
> 
> Reordering is needed to ensure the following node_set() is not called
> with an invalid nid.
> While doing that, I thought the start == end condition is the same
> kind of invalid blk, so I moved it into the warning block.
> But no strong opinion here though. Should I go back to not printing
> the warning for start == end in v2?

Yeah, please skip the warning in v2.
 
> > --
> > Sincerely yours,
> > Mike.
> >
> 
> Best Regards,
> Sang-Heon Jeon

-- 
Sincerely yours,
Mike.