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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261021_142740_882317_61F3C3F6 X-CRM114-Status: GOOD ( 22.91 ) X-Spam-Score: -9.5 (---------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-21.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIMWL_WL_MED,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Wed, Oct 21, 2026 at 2:33=E2=80=AFAM Muchun Song = wrote: > > On Oct 3, 2026, at 08:21, James Houghton wrote: > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > > index a1b51251103b..4dac7ed1df57 100644 > > --- a/mm/hugetlb.c > > +++ b/mm/hugetlb.c > > @@ -1613,9 +1613,14 @@ static void bulk_vmemmap_restore_error(struct hs= tate *h, > > * page is made a surplus page and removed from the list. > > * If are able to restore vmemmap and free one hugetlb pag= e, we > > * quit processing the list to retry the bulk operation. > > + * > > + * Folios whose vmemmap was never optimized (e.g. because = HVO > > + * failed when they were allocated) can be freed right awa= y; > > + * remove_hugetlb_folio() has already cleared their hugetl= b flag. > > Since you mentioned the hugetlb flag is cleared. So it's unnecessary to c= lear it again. > > > */ > > list_for_each_entry_safe(folio, t_folio, folio_list, lru) > > - if (hugetlb_vmemmap_restore_folio(h, folio)) { > > + if (folio_test_hugetlb_vmemmap_optimized(folio) &= & > > + hugetlb_vmemmap_restore_folio(h, folio)) { > > list_del(&folio->lru); > > spin_lock_irq(&hugetlb_lock); > > add_hugetlb_folio(h, folio, true); > > Something like following: > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 6a011b627986..1ab3e61f4704 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1616,21 +1616,31 @@ static void bulk_vmemmap_restore_error(struct hst= ate *h, > * If are able to restore vmemmap and free one hugetlb pa= ge, we > * quit processing the list to retry the bulk operation. > */ > - list_for_each_entry_safe(folio, t_folio, folio_list, lru) > - if (hugetlb_vmemmap_restore_folio(h, folio)) { > - list_del(&folio->lru); > + list_for_each_entry_safe(folio, t_folio, folio_list, lru)= { > + list_del(&folio->lru); > + > + /* > + * remove_hugetlb_folio() already cleared the hug= etlb flag > + * for folios whose vmemmap was not optimized, so= they can > + * be freed without restoring vmemmap. > + */ > + if (folio_test_hugetlb(folio) && > + hugetlb_vmemmap_restore_folio(h, folio)) { > spin_lock_irq(&hugetlb_lock); > add_hugetlb_folio(h, folio, true); > spin_unlock_irq(&hugetlb_lock); > - } else { > - list_del(&folio->lru); > + continue; > + } > + > + if (folio_test_hugetlb(folio)) { > spin_lock_irq(&hugetlb_lock); > __folio_clear_hugetlb(folio); > spin_unlock_irq(&hugetlb_lock); > - update_and_free_hugetlb_folio(h, folio, f= alse); > - cond_resched(); > - break; > } > + update_and_free_hugetlb_folio(h, folio, false); > + cond_resched(); > + break; > + } > } > } Thanks, Muchun. :) I think it's slightly easier to read without the second folio_test_hugetlb(), like this: list_for_each_entry_safe(folio, t_folio, folio_list, lru) { list_del(&folio->lru); /* * remove_hugetlb_folio() already cleared the hugetlb flag * for folios whose vmemmap was not optimized, so they can * be freed without restoring vmemmap. */ if (folio_test_hugetlb(folio)) { if (hugetlb_vmemmap_restore_folio(h, folio)) { spin_lock_irq(&hugetlb_lock); add_hugetlb_folio(h, folio, true); spin_unlock_irq(&hugetlb_lock); continue; } spin_lock_irq(&hugetlb_lock); __folio_clear_hugetlb(folio); spin_unlock_irq(&hugetlb_lock); } update_and_free_hugetlb_folio(h, folio, false); cond_resched(); break; } Applied this in the v3.