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Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Qi Zheng , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20260929053231.66085-1-songmuchun@bytedance.com> <20260929143214.9061bcf284369163192968d1@linux-foundation.org> To: Andrew Morton X-Mailer: Apple Mail (2.3901.100.1.1.11) X-Rspam-User: X-Stat-Signature: 8rix9jm4w54u36de6eaj9fbqa1pb57uu X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 46D5FA0004 X-HE-Tag: 1790731590-667642 X-HE-Meta: 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 K6aKxl5U S8Xb6HkRzcfEvdDaUO5vyOCvhTSDzec9pQ1tWs8vuq7vLA+7q53+FIb5vqUAZbmj1d3pcXRs3zZ0WS1Lc/i8/b9bqy2aU/l7oDUAL4em9PgUDc5cn/EJtGBH2BHt3QfmmRmbdWHlf6AewvzGtljuV/Wr0U6Gtzhi9rp4PskwwvAdo1kxr740PJLwpUBvSxAD6eUIoYkixZN0QRxvsSkU5NAEg8mCkw37TOXlIgptQnEBY9TskjcXsqk7+Xa0KisMa5WsnU0/peT5r2Yf44PZuJwgI1rWxkgUEE+6VBiJ8TVyq156D6IxpBwEAXnQwxHegE1Ay+xckj1FOZt3U/fS+7R6wN2TfKJknCqm82uE/EYwmEQtk9nsjKvS4Ym0dbTEL6bntDlcKjvNuIYVzC1+TetOb7G7ovf4jUJIXZ6x05iR/rVE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Sep 30, 2026, at 05:32, Andrew Morton = wrote: >=20 > On Tue, 29 Sep 2026 13:32:25 +0800 Muchun Song = wrote: >=20 >> This v3 is based on mm-new commit 2ddb90ee544a, which contains v5 of >> "mm: Switch device DAX to section-based vmemmap optimization" [1]. >>=20 >> This series is split out from the earlier, larger series "mm: = Generalize >> HVO for HugeTLB and device DAX" [2]. While the parent series = generalizes >> vmemmap optimization across HugeTLB and device DAX, this subset = addresses >> a single, self-contained step: unifying their vmemmap population = paths. >>=20 >> After the preceding Device DAX conversion, both HugeTLB and Device = DAX >> describe optimized vmemmap mappings through memory-section metadata = and >> use per-zone shared tail vmemmap pages. The generic code, however, = still >> carries a Device DAX-specific population flag and compound-page = population >> path, along with arguments and helpers needed only by that path. >>=20 >> This series first removes VMEMMAP_POPULATE_DAX and moves selection = and >> reference handling for the shared tail page into the common vmemmap >> population path. It then removes the generic Device DAX-specific >> compound-page population path and routes section vmemmap population >> through vmemmap_populate(). The powerpc radix path continues to use = its >> architecture-specific compound-page population implementation for >> optimizable sections. >>=20 >> The remaining patches remove the unused ptpfn argument, open-code >> vmemmap_populate_address() now that no caller needs its returned PTE, = and >> add a warning for inconsistent zone initialization of shared tail = vmemmap >> pages. >>=20 >> This is the fourth smaller step toward the broader HVO = generalization. >> After this series, HugeTLB and Device DAX use the same population = model >> instead of parallel generic paths, while powerpc keeps its >> architecture-specific implementation. >=20 > afaict the whole series is "no functional changes intended". Apart > from [6/6]'s new WARN_ON. Yes. >=20 > And [3/6] is the one which could cause unintended fuctional changes! Understood. However, the resulting vmemmap layout is intended to remain unchanged. >=20 > Thanks. I'll queue it. Reluctantly. We're up to 688 MM patches this > cycle and it's time to stop. Thanks for taking it despite the load. Muchun, Thanks.