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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240627201737.3506959-1-nphamcs@gmail.com> X-Stat-Signature: 6dj4t8to896sih3x1h78gnb5bbi4mgcp X-Rspam-User: X-Rspamd-Queue-Id: 95451A0013 X-Rspamd-Server: rspam02 X-HE-Tag: 1719520879-376167 X-HE-Meta: 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 EgcgJVIU 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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: List-Subscribe: List-Unsubscribe: On Thu, Jun 27, 2024 at 01:17:37PM -0700, Nhat Pham wrote: > syzbot detects that cachestat() is flushing stats, which can sleep, in > its RCU read section (see [1]). This is done in the > workingset_test_recent() step (which checks if the folio's eviction is > recent). > > Move the stat flushing step to before the RCU read section of cachestat, > and skip stat flushing during the recency check. > > [1]: https://lore.kernel.org/cgroups/000000000000f71227061bdf97e0@google.com/ > > Reported-by: syzbot+b7f13b2d0cc156edf61a@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/cgroups/000000000000f71227061bdf97e0@google.com/ > Debugged-by: Johannes Weiner > Suggested-by: Johannes Weiner > Signed-off-by: Nhat Pham > Fixes: b00684722262 ("mm: workingset: move the stats flush into workingset_test_recent()") > Cc: stable@vger.kernel.org # v6.8+ Acked-by: Johannes Weiner