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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: E094B20004 X-Stat-Signature: 73hepy6gd6n76ddm1cfkd6bn4z7uccsg X-HE-Tag: 1788614642-952287 X-HE-Meta: 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 GqrsAyAH YJPVQgTUNFjluNufbkTDlGa4QpFaAgQd6RJAGN2QzcZbwlJJ/nMJhVby5ZO1OMqcBQeyCeMlh+MGrBGOO7fz8hbnyVoLJkAyQiWDHwPvjg66PnBuM8GGq3NSOPyHfgm2gSGNwksGgTSz9MRhiOLJUoY7UKeD2ZJl9msDJEeEz81xpsBABNRqjzNHumTjakzquWw1D09z7BifgBxLpPygNDLH5jXwT4HwTY2mms70qB6iwgNyg3q1OX7ETfqDtWOmk0nAgtxJUcLkNseYWn3+5vycQRU9FmmjkT5qvyT+q36z29h8EHqTbE7Qm0eUzkKW33xX/BYH/Z0gvYKKejuoaPmISKseV761k2n6Gl22oZEl523bWOmo7gOJ7U5WCrMBXpPUEQJEUOmhr8+icpAhQFb3B6Q== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, 2026-09-05 at 14:18 +0800, Jinjiang Tu wrote: >=20 > diff --git a/mm/rmap.c b/mm/rmap.c > index d1819fd69938..a868e835eadb 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -209,7 +209,11 @@ int __anon_vma_prepare(struct vm_area_struct > *vma) > =C2=A0 /* page_table_lock to protect against threads */ > =C2=A0 spin_lock(&mm->page_table_lock); > =C2=A0 if (likely(!vma->anon_vma)) { > - vma->anon_vma =3D anon_vma; > + /* > + * The fields of anon_vma must be visible before > anon_vma > + * is published to vma->anon_vma. > + */ > + smp_store_release(&vma->anon_vma, anon_vma); > =C2=A0 anon_vma_chain_assign(vma, avc, anon_vma); > =C2=A0 anon_rmap_tree_insert(avc, anon_vma); > =C2=A0 anon_vma->num_active_vmas++; Nice catch on this bug! This is perhaps a dumb question, but does this write side barrier need to pair with a read side barrier, to ensure the reads are also correctly ordered? --=20 All Rights Reversed.