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

[Thorsten Leemhuis <regressions@leemhuis.info>]

On 05.09.24 08:42, Yu Zhao wrote:
> On Thu, Sep 5, 2024 at 12:21 AM Chris Li <chrisl@kernel.org> 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@mail.gmail.com/
>> Fixes: 33dfe9204f29 ("mm/gup: clear the LRU flag of a page before adding to LRU batch")
>> Suggested-by: Yu Zhao <yuzhao@google.com>
>> Suggested-by: Hugh Dickins <hughd@google.com>
>> Tested-by: Chris Li <chrisl@kernel.org>
>> Signed-off-by: Chris Li <chrisl@kernel.org>

Thx for taking care of this, Chris!

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

FWIW, no big deal, but that ideally should be (in general and for
regression tracking) the following instead, as that link above is just
at the end of the thread with the report, but not the report itself --
and that is what often needed when someone needs to look up the
backstory of this chance sooner or later:

Closes:
https://lore.kernel.org/all/CAF8kJuNP5iTj2p07QgHSGOJsiUfYpJ2f4R1Q5-3BN9JiD9W_KA@mail.gmail.com/

Ciao, Thorsten