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charset=us-ascii Content-Disposition: inline In-Reply-To: <68e9715a.050a0220.1186a4.000d.GAE@google.com> X-Rspam-User: X-Rspamd-Queue-Id: 08669100004 X-Rspamd-Server: rspam10 X-Stat-Signature: fu56k97g5rs6izkhgsdn7tuiip7f8yef X-HE-Tag: 1767883174-35950 X-HE-Meta: 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 geDYIzh8 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 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 Fri, Oct 10, 2025 at 01:49:30PM -0700, syzbot wrote: > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=133e89e2580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f3ba7c580000 #syz test diff --git a/mm/migrate.c b/mm/migrate.c index 5169f9717f60..4688b9e38cd2 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1458,6 +1458,7 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio, int page_was_mapped = 0; struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; + enum ttu_flags ttu = 0; if (folio_ref_count(src) == 1) { /* page was freed from under us. So we are done. */ @@ -1498,8 +1499,6 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio, goto put_anon; if (folio_mapped(src)) { - enum ttu_flags ttu = 0; - if (!folio_test_anon(src)) { /* * In shared mappings, try_to_unmap could potentially @@ -1516,16 +1515,17 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio, try_to_migrate(src, ttu); page_was_mapped = 1; - - if (ttu & TTU_RMAP_LOCKED) - i_mmap_unlock_write(mapping); } if (!folio_mapped(src)) rc = move_to_new_folio(dst, src, mode); if (page_was_mapped) - remove_migration_ptes(src, !rc ? dst : src, 0); + remove_migration_ptes(src, !rc ? dst : src, + ttu ? RMP_LOCKED : 0); + + if (ttu & TTU_RMAP_LOCKED) + i_mmap_unlock_write(mapping); unlock_put_anon: folio_unlock(dst);