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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0E78F40004 X-Stat-Signature: unpp95zhmpn6giq13cknz8foynawadh4 X-Rspam-User: X-HE-Tag: 1765899399-141868 X-HE-Meta: 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 8Q4ESSC8 fBBuQUsMf1U7R4gv6ketjVb49TSKI3iZ85tovHD+k0cNXAtWlcULuh+OuPQufE/wtXji0J+LQn5mTEXpMV/tqEfWdZ++6BN9V8OGW9tWYIyfguNkEhvxAWL+10qBeHJadLbywBaJJRUkVK6WoL0lAuberiBrENTRMOo/K+DjTXW42pZTieUeJ+fAtbi1ACzAoKBosQOLza2iNy+7ZQ1I0WC6AKQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Dec 16, 2025 at 10:19=E2=80=AFAM Mike Rapoport wr= ote: > > On Tue, Dec 16, 2025 at 10:05:27AM -0500, Pasha Tatashin wrote: > > > > +static struct page *__init kho_get_preserved_page(phys_addr_t phys= , > > > > + unsigned int order) > > > > +{ > > > > + unsigned long pfn =3D PHYS_PFN(phys); > > > > + int nid =3D early_pfn_to_nid(pfn); > > > > + > > > > + for (int i =3D 0; i < (1 << order); i++) > > > > + init_deferred_page(pfn + i, nid); > > > > > > This will skip pages below node->first_deferred_pfn, we need to use > > > __init_page_from_nid() here. > > > > Mike, but those struct pages should be initialized early anyway. If > > they are not yet initialized we have a problem, as they are going to > > be re-initialized later. > > Can say I understand your point. Which pages should be initialized earlt? All pages below node->first_deferred_pfn. > And which pages will be reinitialized? kho_memory_init() is called after free_area_init() (which calls memmap_init_range to initialize low memory struct pages). So, if we use __init_page_from_nid() as suggested, we would be blindly running __init_single_page() again on those low-memory pages that memmap_init_range() already set up. This would cause double initialization and corruptions due to losing the order information. > > > > + > > > > + return pfn_to_page(pfn); > > > > +} > > > > + > > > > static void __init deserialize_bitmap(unsigned int order, > > > > struct khoser_mem_bitmap_ptr *e= lm) > > > > { > > > > @@ -449,7 +466,7 @@ static void __init deserialize_bitmap(unsigned = int order, > > > > int sz =3D 1 << (order + PAGE_SHIFT); > > > > phys_addr_t phys =3D > > > > elm->phys_start + (bit << (order + PAGE_SHIFT= )); > > > > - struct page *page =3D phys_to_page(phys); > > > > + struct page *page =3D kho_get_preserved_page(phys, or= der); > > > > > > I think it's better to initialize deferred struct pages later in > > > kho_restore_page. deserialize_bitmap() runs before SMP and it already= does > > > > The KHO memory should still be accessible early in boot, right? > > The memory is accessible. And we anyway should not use struct page for > preserved memory before kho_restore_{folio,pages}. This makes sense, what happens if someone calls kho_restore_folio() before deferred pages are initialized?