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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 463FF140010 X-Stat-Signature: xrnbxqiuqonopgqu4wi4ae3km9urddzu X-Rspam-User: X-HE-Tag: 1680821876-502964 X-HE-Meta: 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 C4Ez6y1F 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 6, 2023 at 1:20=E2=80=AFAM Naoya Horiguchi wrote: > > From: Naoya Horiguchi > > split_huge_page_to_list() WARNs when called for huge zero pages, which > sounds to me too harsh because it does not imply a kernel bug, but just > notifies the event to admins. On the other hand, this is considered > as critical by syzkaller and makes its testing less efficient, which > seems to me harmful. > > So replace the VM_WARN_ON_ONCE_FOLIO with pr_warn_ratelimited. Makes sense to me. Reviewed-by: Yang Shi > > Fixes: 478d134e9506 ("mm/huge_memory: do not overkill when splitting huge= _zero_page") > Reported-by: syzbot+07a218429c8d19b1fb25@syzkaller.appspotmail.com > Link: https://lore.kernel.org/lkml/000000000000a6f34a05e6efcd01@google.co= m/ > Signed-off-by: Naoya Horiguchi > Cc: stable@vger.kernel.org > --- > mm/huge_memory.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 81a5689806af..06bcdd6f5060 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2649,9 +2649,10 @@ int split_huge_page_to_list(struct page *page, str= uct list_head *list) > VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); > > is_hzp =3D is_huge_zero_page(&folio->page); > - VM_WARN_ON_ONCE_FOLIO(is_hzp, folio); > - if (is_hzp) > + if (is_hzp) { > + pr_warn_ratelimited("Called split_huge_page for huge zero= page\n"); > return -EBUSY; > + } > > if (folio_test_writeback(folio)) > return -EBUSY; > -- > 2.25.1 >