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From: Muchun Song In-Reply-To: <20260720093127.540540-9-songmuchun@bytedance.com> Date: Mon, 20 Jul 2026 19:10:23 +0800 Cc: Andrew Morton , Oscar Salvador , David Hildenbrand , Mike Rapoport , Vlastimil Babka , Lorenzo Stoakes , Michal Hocko , David Laight , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20260720093127.540540-1-songmuchun@bytedance.com> <20260720093127.540540-9-songmuchun@bytedance.com> To: Muchun Song X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 8157280006 X-Stat-Signature: k39n3ue8ioj5e76igiappcoocc4pn6yd X-HE-Tag: 1784545855-40094 X-HE-Meta: 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 N2NiMeh1 MBFQupBi7iCMHnsBuur34hXKWwiTD9ttNn27Mwf8R6ozkb+kpsvO2g8VQhX4uhn2UNbgIfGelekHS4gGZQVZvgyB8kU3vFjVtsOKVuQ5GjNboumR0zS1ebNWQVUb4+pUHZHA3Q+LWSOUyh0tjeNrH/HQlOsWhCnnU8Q/dzjUqp58AuZ3ZQFRCMeyAm05QlAG/ssc1FrelCgNqeZWguQm8IO4dmxYgq+j6d4KY+3LxyMfLuzv0IUF2sJij4yeIX29onZhZr9WcVR3dudAqSAKi2YuRHMq540ofccBXjSZPtRKCUUtuyH/B5bSOtrFm20LOI6Ys6aZddNFRodPgh4j9TJqNBCrifd/bhgQwG72zx8rFAkiAMuHYyWI8lRYGkh71rQG8AyzZuAnY/kE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Jul 20, 2026, at 17:31, Muchun Song = wrote: >=20 > Teach sparse-vmemmap population code to use the compound page order > when deciding whether a vmemmap page can be optimized. >=20 > With this information, the common sparse-vmemmap population path can > allocate or reuse shared tail vmemmap pages directly instead of = relying > on HugeTLB-specific handling. >=20 > This centralizes vmemmap optimization logic in the sparse-vmemmap = code, > based on section metadata, and prepares for sharing the same mechanism > across different users of vmemmap optimization, including HugeTLB and > DAX. >=20 > Signed-off-by: Muchun Song Sashiko reported four issues [1] regarding memory hotplug, but the = entire series doesn't actually support applying HVO via memory hotplug. = Therefore, all four of these issues are false positives. [1] = https://sashiko.dev/#/patchset/20260720093127.540540-1-songmuchun%40byteda= nce.com?part=3D8=