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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Dan Williams , linux-mm@kvack.org, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, muchun.song@linux.dev References: <20261018043501.3257632-1-songmuchun@bytedance.com> Content-Language: en-US From: "Jose A. Perez de Azpillaga" In-Reply-To: <20261018043501.3257632-1-songmuchun@bytedance.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/18/26 6:35 AM, Muchun Song wrote: > - if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) { > + if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE && > + pmd_none(*pmd)) { > pmd_populate_kernel(&init_mm, pmd, > lm_alias(kasan_early_shadow_pte)); what if the entry already points at the early shadow table? this walks down into it then, which loongarch does on every boot. [snip] > - zero_pmd_populate(pud, addr, next); > + ret = zero_pmd_populate(pud, addr, next, mask); > + if (ret) > + return ret; isn't this a separate fix? it's not in the changelog. [snip] > if (kasan_pud_table(*p4d)) { > + if (ARCH_PAGE_TABLE_SYNC_MASK & PGTBL_P4D_MODIFIED) > + continue; > + doesn't this leave the range on the zero shadow, which memory onlined there later then keeps? would always allocating a table at the synced level once slab is up avoid that? -- cheers, jose a. p-a