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Howlett" , "Vlastimil Babka" , "Mike Rapoport" , "Suren Baghdasaryan" , "Michal Hocko" , "David Rientjes" , "Shakeel Butt" , "Andrew Morton" , "Jann Horn" , "Pedro Falcato" , =?utf-8?b?TWF0dGhldyBXaWxjb3ggKE9yYWNsZSk=?= , "Jan Kara" , "Nhat Pham" , "Johannes Weiner" , "Zi Yan" , "Matthew Brost" , "Joshua Hahn" , "Byungchul Park" , "Gregory Price" , "Ying Huang" , "Alistair Popple" , "Usama Arif" , "Kairui Song" , "Balbir Singh" , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , "Kiryl Shutsemau" , "Yu-cheng Yu" , "Dave Hansen" , "Dennis Zhou" , "Tejun Heo" , "Christoph Lameter" , "Peng Fan" , "Josef Bacik" , "Chris Mason" Cc: linux-mm@kvack.org, =?utf-8?b?Qm9yaXNsYXYgUGV0a292IChBTUQp?= , "Mark Brown" , =?utf-8?b?RGVubmlzIFpob3UgKEZhY2Vib29rKQ==?= , "Rick Edgecombe" , "Josef Bacik" In-Reply-To: <20261111-mason-migrate-et-al-fixes-v1-4-3d2454362e8d@kernel.org> References: <20261111-mason-migrate-et-al-fixes-v1-0-3d2454362e8d@kernel.org> <20261111-mason-migrate-et-al-fixes-v1-4-3d2454362e8d@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 12 Nov 2026 18:16:24 +0000 X-Stat-Signature: zbqhjpdg5xw3x964y7fw7i3o8e65nzso X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 3A105180008 X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1794507387-206598 X-HE-Meta: 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 ZjyitXaK 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: Thank you for your contribution! Sashiko AI review found 1 potential issue to consider: - [Low] mm/migrate_device: duplicate folio_memcg_alloc_deferred() call and dead store -- commit fe6e0150a0f9ab0dcf43e8c18734d603b5d63191 Author: Josef Bacik mm/migrate_device: allocate THP deferred split heads This commit calls folio_memcg_alloc_deferred() after charging the folio in migrate_vma_insert_huge_pmd_page() and falls back if the allocation fails. > diff --git a/mm/migrate_device.c b/mm/migrate_device.c > index 7919e04abc1c5..edcc13edbf6af 100644 > --- a/mm/migrate_device.c > +++ b/mm/migrate_device.c > @@ -840,6 +840,13 @@ static int migrate_vma_insert_huge_pmd_page(struct m= igrate_vma *migrate, > goto abort; > } > =20 > + if (folio_memcg_alloc_deferred(folio)) { > + count_vm_event(THP_FAULT_FALLBACK); > + count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_FALLBACK); > + ret =3D -ENOMEM; > + goto abort; > + } > + > __folio_mark_uptodate(folio); > =20 > pgtable =3D pte_alloc_one(vma->vm_mm); [Severity: Low] Does this duplicate the folio_memcg_alloc_deferred() check that commit ccb36031e6c7 ("mm/migrate_device: allocate deferred split sublists for new huge folios") already added immediately above? mm/migrate_device.c:migrate_vma_insert_huge_pmd_page() { ... /* The charged memcg needs its own sublist before deferred splitting. */ if (folio_memcg_alloc_deferred(folio)) { count_vm_event(THP_FAULT_FALLBACK); count_mthp_stat(HPAGE_PMD_ORDER, MTHP_STAT_ANON_FAULT_FALLBACK); goto abort; } if (folio_memcg_alloc_deferred(folio)) { ... } This calls folio_memcg_alloc_deferred() twice in a row. In addition, setting ret =3D -ENOMEM before jumping to abort is a dead store because the abort label clears MIGRATE_PFN_MIGRATE and returns 0 without reading ret. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261111-mason-migr= ate-et-al-fixes-v1-0-3d2454362e8d@kernel.org?part=3D4