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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: md4npqifpr8y9amjbj7piq4firorngob X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 0272C18000F X-HE-Tag: 1762024376-398544 X-HE-Meta: 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 lOaeP1l3 pokNvAHElXATVHMZAuszKDR+XRsUO0Qsk9ZP561u9r078KAHLiAXOQtCjaI2e3cK24hESc1PzJ+SaHKs3risCDh+HY3jpG+yoxbbKxNGGyiVWIfRQsoJ9IoV2TV7oApEQD4eTBqCMapCgRQWb62X+83gjS622qQAhVzERxCn5/r6Lq1Y8HHKIWx7gqbie3oEOBMvoJM1U7T+AgiVYLrJfadUnijY3/xy4hjOSzFJCIiSuJuRgqe3fMmxERbirSR6ufXa68ZnwrQ5vfxRD50oCy/eD/9UG0vNE62G4JxO3hHTfUTg1Ifwf7vRlroCN/zKpMyIo6/vAiBNViB8= 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 Sat, Nov 1, 2025 at 6:42=E2=80=AFAM Youngjun Park wrote: > > After commit 4f78252da887, nr_swap_pages is decremented in > swap_range_alloc(). Since cluster_alloc_swap_entry() calls > swap_range_alloc() internally, the decrement in get_swap_page_of_type() > causes double-decrementing. > > Remove the duplicate decrement. Acked-by: Chris Li Thanks for the good catch. Indeed there is duplication, but only affects the hibernation usage of swap as far as I can tell. This bug is in v6.17-rc1 upwards including v6.17 as well. You might want to add the stable tag: Cc: stable@vger.kernel.org # v6.17-rc1 Hi Andrew, Please apply. Can you add the above line or Youngjun needs to send out a new version to include the stable line? Chris > > Fixes: 4f78252da887 ("mm: swap: move nr_swap_pages counter decrement from= folio_alloc_swap() to swap_range_alloc()") > Signed-off-by: Youngjun Park > > diff --git a/mm/swapfile.c b/mm/swapfile.c > index 543f303f101d..66a502cd747b 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -2020,10 +2020,8 @@ swp_entry_t get_swap_page_of_type(int type) > local_lock(&percpu_swap_cluster.lock); > offset =3D cluster_alloc_swap_entry(si, 0, 1); > local_unlock(&percpu_swap_cluster.lock); > - if (offset) { > + if (offset) > entry =3D swp_entry(si->type, offset); > - atomic_long_dec(&nr_swap_pages); > - } > } > put_swap_device(si); > } > -- > 2.34.1 >