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BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237c25ea8 of 1 bytes by task 17028 on cpu 0:
 folio_batch_reinit include/linux/pagevec.h:50 [inline]
 folios_put_refs+0x285/0x2d0 mm/swap.c:993
 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
 shmem_alloc_and_add_folio mm/shmem.c:2006 [inline]
 shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2597
 shmem_fault+0xf6/0x250 mm/shmem.c:2798
 __do_fault+0xbc/0x200 mm/memory.c:5152
 do_shared_fault mm/memory.c:5637 [inline]
 do_fault mm/memory.c:5711 [inline]
 do_pte_missing mm/memory.c:4234 [inline]
 handle_pte_fault mm/memory.c:6052 [inline]
 __handle_mm_fault mm/memory.c:6195 [inline]
 handle_mm_fault+0xd69/0x2c20 mm/memory.c:6364
 faultin_page mm/gup.c:1144 [inline]
 __get_user_pages+0x102e/0x1fa0 mm/gup.c:1446
 __get_user_pages_locked mm/gup.c:1712 [inline]
 __gup_longterm_locked+0x58b/0xe60 mm/gup.c:2501
 gup_fast_fallback+0x1f5/0x1420 mm/gup.c:3240
 pin_user_pages_fast+0x5f/0x90 mm/gup.c:3346
 io_pin_pages+0xb5/0x170 io_uring/memmap.c:63
 io_sqe_buffer_register+0x184/0x1430 io_uring/rsrc.c:798
 io_sqe_buffers_register+0x2ac/0x530 io_uring/rsrc.c:913
 __io_uring_register io_uring/register.c:660 [inline]
 __do_sys_io_uring_register io_uring/register.c:929 [inline]
 __se_sys_io_uring_register+0xa9f/0xeb0 io_uring/register.c:906
 __x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:906
 x64_sys_call+0x18a3/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:428
 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 0xffff888237c25ea8 of 1 bytes by task 16996 on cpu 1:
 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: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 16996 Comm: syz.0.5660 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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