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BUG: KCSAN: data-race in folios_put_refs / need_mlock_drain

write to 0xffff888237d26a10 of 1 bytes by task 21971 on cpu 1:
 folio_batch_reinit include/linux/pagevec.h:50 [inline]
 folios_put_refs+0x285/0x2d0 mm/swap.c:986
 folios_put include/linux/mm.h:1415 [inline]
 mlock_folio_batch+0x1a5b/0x1a70 mm/mlock.c:209
 mlock_new_folio+0x1a3/0x200 mm/mlock.c:282
 folio_add_lru_vma+0x5f/0x70 mm/swap.c:522
 do_anonymous_page mm/memory.c:5118 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6069 [inline]
 __handle_mm_fault mm/memory.c:6212 [inline]
 handle_mm_fault+0x27e0/0x2be0 mm/memory.c:6381
 faultin_page mm/gup.c:1186 [inline]
 __get_user_pages+0x1036/0x1fb0 mm/gup.c:1488
 populate_vma_page_range mm/gup.c:1926 [inline]
 __mm_populate+0x243/0x3a0 mm/gup.c:2029
 mm_populate include/linux/mm.h:3348 [inline]
 do_mremap mm/mremap.c:1733 [inline]
 __do_sys_mremap mm/mremap.c:1782 [inline]
 __se_sys_mremap+0x640/0x6f0 mm/mremap.c:1750
 __x64_sys_mremap+0x67/0x80 mm/mremap.c:1750
 x64_sys_call+0x2ba9/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:26
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d26a10 of 1 bytes by task 22017 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 need_mlock_drain+0x30/0x50 mm/mlock.c:235
 cpu_needs_drain mm/swap.c:779 [inline]
 __lru_add_drain_all+0x220/0x3f0 mm/swap.c:867
 lru_cache_disable+0x1f/0x30 mm/swap.c:920
 do_migrate_pages+0x3a/0x5a0 mm/mempolicy.c:1271
 kernel_migrate_pages mm/mempolicy.c:1861 [inline]
 __do_sys_migrate_pages mm/mempolicy.c:1879 [inline]
 __se_sys_migrate_pages+0x2aa/0x310 mm/mempolicy.c:1875
 __x64_sys_migrate_pages+0x55/0x70 mm/mempolicy.c:1875
 x64_sys_call+0x2b5c/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:257
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x03 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 22017 Comm: syz.2.6542 Not tainted 6.16.0-rc3-syzkaller-00329-gdfba48a70cb6 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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