Re: [PATCH] mm/vmscan: fix uninitialized variable in demote_folio_list()

[Bing Jiao <bingjiao@google.com>]

On Fri, Jan 09, 2026 at 05:28:11PM -0800, SeongJae Park wrote:
> On Fri,  9 Jan 2026 05:59:37 +0000 Bing Jiao <bingjiao@google.com> wrote:
>
> > Commit d92027a5f30a6c ("mm/vmscan: select the closest preferred node in
> > demote_folio_list()") refactored the selection logic for demotion target
> > nodes. However, it removed the initial assignment of 'target_nid' while
> > leaving a premature check for 'NUMA_NO_NODE' in place.
> >
> > Since 'target_nid' is now assigned further down in the function based on
> > preferred and allowed node masks, the initial check at line 1046 is
> > redundant.
> >
> > Remove the redundant check to resolve the compiler warning.
> >
> > Reported-by: kernel test robot <lkp@intel.com>
> > Closes: https://lore.kernel.org/oe-kbuild-all/202601091037.vUSHeJCH-lkp@intel.com/
> > Fixes: d92027a5f30a6c ("mm/vmscan: select the closest preferred node in demote_folio_list()")
>
> Seems the broken commit is on mm-new, and therefore no need to Cc stable@.  I
> think explicitly clarifying that would be nice.  Also, as this fixup may need
> to be squashed into the broken commit before it is pulled into the mainline,
> sending this kind of fixup as a reply to the patch mail [1] of the commit would
> also be nice, and usual in mm.
>
> [1] https://lkml.kernel.org/r/20260108033248.2791579-3-bingjiao@google.com
>
> > Signed-off-by: Bing Jiao <bingjiao@google.com>
>
> Reviewed-by: SeongJae Park <sj@kernel.org>
>
>
> Thanks,
> SJ
>
> [...]

Hi SeongJae,

Thank you for the review and suggestions! The patch has sent to the patch
mail you mentioned.

Have a great weekend!

Best regards,
Bing