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

[SeongJae Park <sj@kernel.org>]

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

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