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BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237d25ea8 of 1 bytes by task 31260 on cpu 1:
 folios_put_refs+0x25c/0x2d0 mm/swap.c:997
 folios_put include/linux/mm.h:1419 [inline]
 folio_batch_move_lru+0x24b/0x280 mm/swap.c:179
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x14a/0x1f0 mm/swap.c:511
 folio_add_lru_vma+0x49/0x70 mm/swap.c:530
 wp_page_copy mm/memory.c:3620 [inline]
 do_wp_page+0x1458/0x24e0 mm/memory.c:4013
 handle_pte_fault mm/memory.c:6068 [inline]
 __handle_mm_fault mm/memory.c:6195 [inline]
 handle_mm_fault+0x77d/0x2c20 mm/memory.c:6364
 do_user_addr_fault+0x3fe/0x1090 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
 __put_user_4+0xd/0x20 arch/x86/lib/putuser.S:92
 schedule_tail+0x40/0xa0 kernel/sched/core.c:5292
 ret_from_fork+0x24/0x1b0 arch/x86/kernel/process.c:144
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d25ea8 of 1 bytes by task 31259 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:874
 lru_cache_disable+0x1f/0x30 mm/swap.c:927
 do_mbind mm/mempolicy.c:1456 [inline]
 kernel_mbind mm/mempolicy.c:1682 [inline]
 __do_sys_mbind mm/mempolicy.c:1756 [inline]
 __se_sys_mbind+0x496/0xac0 mm/mempolicy.c:1752
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1752
 x64_sys_call+0x2932/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:238
 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: 0x0f -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 31259 Comm: syz.3.7995 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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