Re: [PATCH] mm: vmscan.c: fix OOM on swap stress test

[Yu Zhao]

On Thu, Sep 5, 2024 at 12:21 AM Chris Li <chrisl@xxxxxxxxxx> wrote:
>
> I found a regression on mm-unstable during my swap stress test,
> using tmpfs to compile linux. The test OOM very soon after
> the make spawns many cc processes.
>
> It bisects down to this change: 33dfe9204f29b415bbc0abb1a50642d1ba94f5e9
> (mm/gup: clear the LRU flag of a page before adding to LRU batch)
>
> Yu Zhao propose the fix: "I think this is one of the potential side
> effects -- Huge mentioned earlier about isolate_lru_folios():"
>
> I test that with it the swap stress test no longer OOM.
>
> Link: https://lore.kernel.org/r/CAOUHufYi9h0kz5uW3LHHS3ZrVwEq-kKp8S6N-MZUmErNAXoXmw@xxxxxxxxxxxxxx/
> Fixes: 33dfe9204f29 ("mm/gup: clear the LRU flag of a page before adding to LRU batch")
> Suggested-by: Yu Zhao <yuzhao@xxxxxxxxxx>
> Suggested-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Tested-by: Chris Li <chrisl@xxxxxxxxxx>
> Signed-off-by: Chris Li <chrisl@xxxxxxxxxx>

Closes: https://lore.kernel.org/56651be8-1466-475f-b1c5-4087995cc5ae@xxxxxxxxxxxxx/