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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: <8385F749-0F72-494E-9CA2-2E433A066712@linux.dev> References: <20260924075259.2013039-1-songmuchun@bytedance.com> <607759bf-59f2-4ad6-b95b-e780ed2acba3@kernel.org> To: "David Hildenbrand (Arm)" X-Mailer: Apple Mail (2.3901.100.1.1.11) > On Sep 28, 2026, at 20:44, David Hildenbrand (Arm) = wrote: >=20 > On 9/24/26 09:52, Muchun Song wrote: >> This series is split out from the earlier, larger series "mm: = Generalize >> HVO for HugeTLB and device DAX" [1]. 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 >> [1] = https://lore.kernel.org/all/20260513130542.35604-1-songmuchun@bytedance.co= m/ >=20 > How does this series relate to >=20 > = https://lore.kernel.org/r/20260927025441.741633-1-songmuchun@bytedance.com= This series is based on the v4 version [1] of the series you pointed = out. When I was sending the current series, the v4 version of that series had = already been in mm-new for some time, so I sent the v2 version of the current = series. However, a couple of days ago the kernel test bot reported an issue, and = this issue cannot be easily fixed with a simple fixup. So I updated that = series to a v5 version. Therefore, the current series needs to be rebased on top of the v5 = version of the series you pointed out, and then sent as a new v3 version before it = can be properly applied or reviewed. If you're planning to review this series, I'd suggest waiting for my = rebased version. [1] = https://lore.kernel.org/all/20260916064341.1825793-1-songmuchun@bytedance.= com/ Thanks, Muchun >=20 > ? >=20 > --=20 > Cheers, >=20 > David