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BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237c25ea8 of 1 bytes by task 13110 on cpu 0:
 folio_batch_reinit include/linux/pagevec.h:50 [inline]
 folios_put_refs+0x285/0x2d0 mm/swap.c:986
 folios_put include/linux/mm.h:1417 [inline]
 folio_batch_move_lru+0x1fd/0x230 mm/swap.c:175
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x14a/0x1f0 mm/swap.c:505
 shmem_alloc_and_add_folio mm/shmem.c:1949 [inline]
 shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2536
 shmem_get_folio mm/shmem.c:2642 [inline]
 shmem_write_begin+0xa8/0x190 mm/shmem.c:3292
 generic_perform_write+0x181/0x490 mm/filemap.c:4141
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3467
 __kernel_write_iter+0x253/0x4c0 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1296 [inline]
 dump_user_range+0x61e/0x8f0 fs/coredump.c:1370
 elf_core_dump+0x1e00/0x1f90 fs/binfmt_elf.c:2085
 coredump_write+0xb0a/0xe30 fs/coredump.c:1049
 vfs_coredump+0x142f/0x20c0 fs/coredump.c:1168
 get_signal+0xd85/0xf70 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
 irqentry_exit_to_user_mode+0x5e/0xa0 kernel/entry/common.c:73
 irqentry_exit+0x12/0x50 kernel/entry/common.c:176
 exc_general_protection+0x15b/0x1f0 arch/x86/kernel/traps.c:792
 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617

read to 0xffff888237c25ea8 of 1 bytes by task 13119 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:773 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:867
 lru_cache_disable+0x1f/0x30 mm/swap.c:920
 do_mbind mm/mempolicy.c:1459 [inline]
 kernel_mbind mm/mempolicy.c:1685 [inline]
 __do_sys_mbind mm/mempolicy.c:1759 [inline]
 __se_sys_mbind+0x496/0xac0 mm/mempolicy.c:1755
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1755
 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: 13119 Comm: syz.7.3044 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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