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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: iijwzu74n6wn7cgkseozrrasc9cnb5yu X-Rspamd-Queue-Id: A187640008 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1725039938-82546 X-HE-Meta: U2FsdGVkX18EIqnFJkAMebAmVm3UF9AJuuV+2KMBNRNV3+RhMpmJIr/+c4Z9xnujPuEp0wj+kphxwFhcxFqvRUa08JDuy8205AqAW/tOnyi2KKl3yViGTkUoFKX+RbVtM859M7suG6gJVpaEoInLh7lrLW1hqMofvM7+vEcHicyLeF0nBgMIDVTPZiBAYgiayVizEh7phk5S/+ep/MBkJZhXvrtAOrtPubfs6NdHc9BO3UAzRLic0s1VBnkfshW2lOr2nN0WIvgzIWlK7Qk4gxt38OikcNl6n8K1OGOgYMQOZBTYSOC41UwsPSySzYba3mEtZxsYN1t3Ahru8sprGCnDSgBEmsXklK4Bl7FcjIC52O9iFqhZHxnfjAsG1GgUlcYX3RthFapRb57OZRIgYLeaeYW944C0s6XY6EriKNAfGMluDGZTL9XQC1HteLTOWakm5Tr0p8QHagb1PApKVObTrJ9AmtvsG8GMpNbYzPZL8F66xXiUO7CfEQygO6Ief9QPSJ7rgdUlTfmGyFv1ASr/5Z3Lgtf0LgZVsRxHmtEtAVx6/TnPjgRDjZ+mANVnyRY+5FjMDVs09IDJxpc8xqhOaKKbx3E1tbjFfNw/EDPUNnPsSvCOTo4OAKRASquRnIMGS5RofqxCNo4OvksTahbBmD0EGXZ13DXzJcGWHf9t5ZhNMH2ABQ6ykSEq2D0y1oEWL/fWrBj2fJIReX4ydpZeQ7hiCsnjYEYrcIWqHJVr4pa/KjTUV8LnmafPBZqN9eQ/FY1JIw1sxdz2YAjvbvPm82GG87v8bCp8I2j3sA4gVf4g51+UVlORWS1sQBN8u4rDtW9erleTtQnOpmlty1EoH8RcO5w/T4p6nhSkmlmeq/dCSDhgzkDXZFFE3JGz/8PQZ/8yEk5R2brSbqQ7u+wrvHEYsUdzg1JXpAW9L6Xfk7WopiGEvUskbIHOFw4JjhVEG8Hal+tNzfYP98x crQTUkF3 gqYf+KTYKSgGbi1nRFTf+FYoXylUjHze4BbWfD4l/ttqCHQBPEweRa7JWFX9uK1TXXtaVmJmSaRCKhXtolacNHRaoda3GQ8v9aYSuSEDLzidnQaMnntWcpApyx1tjRS0jCakt32/SSWOl3L/FQDd+vgeVrs3M5NKGpb0K2Yoc7+8Bct4QdBwglDn1f9y+ti0/K29pZgqKFrDdpFQ3ooHbPstnRfN1cvVE5Utb 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 Fri, Aug 30, 2024 at 3:04=E2=80=AFAM Hugh Dickins wro= te: > > mm-unstable commit 954dd0848c61 needs the fix below to be merged in; > but the commit after it (the 5/5) then renames "memcg" to "next", > so that one has to be adjusted too. > > [PATCH] mm: restart if multiple traversals raced: fix > > mem_cgroup_iter() reset memcg to NULL before the goto restart, so that > goto out_unlock does not then return an ungotten memcg, causing oopses > on stale memcg in many places (often in memcg_rstat_updated()). > > Signed-off-by: Hugh Dickins > --- > mm/memcontrol.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 6f66ac0ad4f0..dd82dd1e1f0a 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1049,6 +1049,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgrou= p *root, > if (cmpxchg(&iter->position, pos, memcg) !=3D pos) { > if (css && css !=3D &root->css) > css_put(css); > + memcg =3D NULL; > goto restart; > } > > -- > 2.35.3 Hi Andrew, Would you prefer that I resend the series with Hugh's fix inserted? Acked-by: Kinsey Ho