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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Jonathan Corbet , Shuah Khan , Randy Dunlap , Peter Xu , Breno Leitao , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Peter Zijlstra , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Arnd Bergmann , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Gerd Hoffmann , linux-doc@vger.kernel.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20261028-fixes_hugetlb-v1-0-a0a033db180f@kernel.org> <20261028-fixes_hugetlb-v1-3-a0a033db180f@kernel.org> To: "David Hildenbrand (Arm)" X-Mailer: Apple Mail (2.3901.100.1.1.12) X-Stat-Signature: g5tkcxe8enjzy1jsyjg6tuc6irfrx95r X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 2FC5DA0002 X-Rspam-User: X-HE-Tag: 1793245304-777376 X-HE-Meta: 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 AxqERp57 RXvG7peaNlPYaRoaK4ZOqYSgaNfuR2gYn++P0tmZrOTlRbaT6JTDqI7kVk2uIn5RNR28hy+VetfJYggMloqAdar7VFbTiDAyr+svXz7xZICtQ1tZC2b24dE4wMIfEKouRUWoRH8fHCMpSHBdb3oZ+j08NC9++Ms/T9FZp+F7vpuk5N2rmnxDYytCsikxkyrTCEn7ogt/sfwg7F0sKTptrJUETUCSqdIXEncFKxsoCmv+seVvF2NxhQuDHvPQrx9Pd7ikPM9BBSsChpWCYAVN1EtRT0vJzoG1eqFc1RdnI/gYOpM1fE7+jyEzPNnuEyoJyZ8Jxm4NFYoshDNv4WzJu5GzTyAm7nm1OtI16msa8yevjrzA= 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 > On Oct 29, 2026, at 04:13, David Hildenbrand (Arm) = wrote: >=20 > try_to_free_low() drops the hugetlb_lock while freeing lowmem folios. > set_max_huge_pages() then resumes freeing folios using the > min_count computed before that unlock. Reservations created in between > can consequently lose their backing. >=20 > Collect lowmem folios on the caller's existing page_list instead. Keep > the hugetlb_lock held through both selection passes, and free the = combined > list at the caller's existing unlock point. >=20 > Likely not stable-worthy. >=20 > Fixes: 1121828a0c21 ("hugetlb: call update_and_free_page without = hugetlb_lock") > Signed-off-by: David Hildenbrand (Arm) Acked-by: Muchun Song Thanks.