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charset=us-ascii Content-Disposition: inline In-Reply-To: <2a3386e7-9b09-f22e-ee39-a37a046d54ec@redhat.com> X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D6C49A0017 X-Stat-Signature: 4c46wc1kyyukek37xnrt64t16eacxhed X-Rspam-User: X-HE-Tag: 1678311055-712395 X-HE-Meta: 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 cEkfn0LF K27xov5G1OnnrI7/SIF5Sn4RdUtbE1X2qXehPVFBhyn3If7hK02Sl0cBzcEzqgUSVL/jAZkPJgNgpeeimWJ/1Z79YaXmbW55pWlGGDRhDQPVMWhUAYqEhNM0xffz1RVTNFTKa599s23euHexMgMKpmMtfYrmgy000v76+RqS85rsKoMQfEhnOfC76rS2P1M1xZNoj6IGchfr1QPILkZ67fV7BDgutkVMXYo9kSk5ipk6dpbjUwqg6oKjPKfhpYmbfwoZLi1BUvWA/L2pVww27ukOdHbQgtpRY4U7VeiGWdDR05JwHyi22wTKBkZ/mmoKkDahARHwlzRu8hyXoV2LGKooHxPVmWzGV/zgV 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 Mon, Mar 06, 2023 at 03:01:52PM +0100, David Hildenbrand wrote: > On 03.03.23 00:27, Luis Chamberlain wrote: > > @@ -1340,6 +1340,18 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) > > swp_entry_t swap; > > pgoff_t index; > > + /* > > + * Our capabilities prevent regular writeback or sync from ever calling > > + * shmem_writepage; but a stacking filesystem might use ->writepage of > > + * its underlying filesystem, in which case tmpfs should write out to > > + * swap only in response to memory pressure, and not for the writeback > > + * threads or sync. > > + */ > > + if (!wbc->for_reclaim) { > > if (WARN_ON_ONCE(!wbc->for_reclaim)) > > > + WARN_ON_ONCE(1); /* Still happens? Tell us about it! */ > > And drop the comment :) That's what WARN_ON_ONCE is all about. Good call, will add that to v2. > Acked-by: David Hildenbrand Great thanks, Luis