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From: Muchun Song In-Reply-To: <20230707123844.adf56ba3e0d000f6da431494@linux-foundation.org> Date: Sat, 8 Jul 2023 09:42:57 +0800 Cc: Muchun Song , Mike Kravetz , Linux Memory Management List , linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <63EDE3B6-B0AD-4D67-8EC6-FC8AE627E352@linux.dev> References: <20230707033859.16148-1-songmuchun@bytedance.com> <20230707123844.adf56ba3e0d000f6da431494@linux-foundation.org> To: Andrew Morton X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: DA91140009 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 7ne7pc8dw6katp69j9fy688kun45fxu9 X-HE-Tag: 1688780614-634147 X-HE-Meta: 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 ZDvYrshj o4+w5DkbfJHlAV6sMar60fXMzbBk1q8iZP04kwYX8BBnwoiLuNce3RGM1KT9Lgsube27qEWcv3T/YrPv4c3udAQjb4eKVu5j6mOFUQggsiJTBE9npFAZCg0X2X5kCq/R8MgNGk5Mz16+CZh82Nos0+f3cQa7ezrMVF6Zc5/808BLTXmlSKno5hxMLPRWNmnccSRejyx0sAgz7V1CsCcUvFnOKQEvq4VtUMXrwJ02Id2lBWdhS64DIYNtKVkP+LkJRcd4Kh0RCgcRowqJajhB8qzgdu+jReTrPGgC4bJZP9soBn/fkX9PFtJSyBA== 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 Jul 8, 2023, at 03:38, Andrew Morton = wrote: >=20 > On Fri, 7 Jul 2023 11:38:59 +0800 Muchun Song = wrote: >=20 >> The local variable @page in __split_vmemmap_huge_pmd() to obtain a = pmd >> page without holding page_table_lock may possiblely get the page = table >> page instead of a huge pmd page. The effect may be in set_pte_at() >> since we may pass an invalid page struct, if set_pte_at() wants to >> access the page struct (e.g. CONFIG_PAGE_TABLE_CHECK is enabled), it >> may crash the kernel. So fix it. And inline = __split_vmemmap_huge_pmd() >> since it only has one user. >=20 > Is this likely enough to justify a backport? >=20 > I'm thinking "add cc:stable and merge into 6.6-rc1", so it hits = -stable > after a couple of months of testing. >=20 Hi Andrew, It is better to backport it to stable. Could you help me add it? Thanks.