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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: B4829A0005 X-Stat-Signature: jyufsbzofoi16xqrhs4ry8gz15d1seuk X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1775087003-297702 X-HE-Meta: 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 ddmKCHMt gK9jP5Ef5uDp5uJlZ9wDif3oOkAraK2SVn3gLB5O1XAdK50SlNmOmI9JfC/agT3gj8heKWOt6FUdTcvkSKnxkdzes7zGYsu65WT0fyz53wTttBWn/p5oXfQvDPcrAZqmYou1Upg7pWiLjGM7qUsa4F9nqWWiR+/UXHJZkpawL3Sr4dZzqETUfkPPAmJGeAylx2gQTfGgGIViWyMhRIdkVFkPkzPJK/dDUtz79Ea7foqlEFW5RJVoyYFscr8383l5XId85UuOHtpLWGmoXdPMTdKxOR1nh6ChMXgTw0X38Tc8nZVfNAgMZAo7yZqgOPL25ad7HfcntrTPsvAIPFWjYa0J72mkdVR20Tzmr1slkrthYIZy5lyOf2zWUi4IXn6tIquQ/F6dt1ztUiYLiC6pNY26ZCg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Apr 1, 2026 at 3:47=E2=80=AFPM David Carlier w= rote: > > sio_read_complete() uses sio->pages to account global PSWPIN vm events, > but sio->pages tracks the number of bvec entries (folios), not base > pages. > > While large folios cannot currently reach this path (SWP_FS_OPS and > SWP_SYNCHRONOUS_IO are mutually exclusive, and mTHP swap-in allocation > is gated on SWP_SYNCHRONOUS_IO), the accounting is semantically > inconsistent with the per-memcg path which correctly uses > folio_nr_pages(). > > Use sio->len >> PAGE_SHIFT instead, which gives the correct base page > count since sio->len is accumulated via folio_size(folio). > > Signed-off-by: David Carlier LGTM, Reviewed-by: Barry Song