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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: jaeogh5fdwmck99h9xqenkxsy6hxbemt X-Rspamd-Queue-Id: C74388000C X-Rspamd-Server: rspam06 X-Rspam-User: X-HE-Tag: 1760545559-836306 X-HE-Meta: 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 89h+4QHu Ia542xF0G8xBchBsmINCUBYQSCxdMcqBAn+cfdfYZIChrKQw0z79vvJAvR3DGZh/Wv0fi+4iUr17H0ibyZT+p9Om1RH/1HbPDJTL8HYt+YEpUAsvlDyuzckxVdZZBcFcr7H2NXvgoL7r6K/GIsIRft740Qm0E4xVs3Yiae28N5bi68CFSxXrVNpijncodusmHeUwSxjU/jS3g/jyxohpxKJq14NMl/cMNnULv5Pkvp11PMQ2dLwvhrznU712MyO1B5DDFNxXTzYk5a3m+9M7KYqI3Ozrr1WDnOcwHVSTFpu7ipiA= 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: Here's the part that confuses me: On 10/14/25 13:59, syzbot ci wrote: > page last free pid 5965 tgid 5964 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1394 [inline] > __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906 > pmd_free_pte_page+0xa1/0xc0 arch/x86/mm/pgtable.c:783 > vmap_try_huge_pmd mm/vmalloc.c:158 [inline] ... So, vmap_try_huge_pmd() did a pmd_free_pte_page(). Yet, somehow, the PMD stuck around so that it *could* be used after being freed. It _looks_ like pmd_free_pte_page() freed the page, returned 0, and made vmap_try_huge_pmd() return early, skipping the pmd pmd_set_huge(). But I don't know how that could possibly happen.