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BUG: KCSAN: data-race in __lru_add_drain_all / folios_put_refs

write to 0xffff888237c25ea8 of 1 bytes by task 3505 on cpu 0:
 folios_put_refs+0x25c/0x2d0 mm/swap.c:995
 folios_put include/linux/mm.h:1419 [inline]
 folio_batch_move_lru+0x1fd/0x230 mm/swap.c:175
 lru_add_drain_cpu+0x77/0x250 mm/swap.c:647
 lru_add_drain mm/swap.c:735 [inline]
 __folio_batch_release+0x44/0xb0 mm/swap.c:1054
 folio_batch_release include/linux/pagevec.h:101 [inline]
 shmem_undo_range+0x344/0xa80 mm/shmem.c:1157
 shmem_truncate_range mm/shmem.c:1269 [inline]
 shmem_evict_inode+0x134/0x520 mm/shmem.c:1397
 evict+0x2e0/0x550 fs/inode.c:810
 iput_final fs/inode.c:1897 [inline]
 iput+0x447/0x5b0 fs/inode.c:1923
 dentry_unlink_inode+0x24f/0x260 fs/dcache.c:466
 __dentry_kill+0x18d/0x4b0 fs/dcache.c:669
 dput+0x5e/0xd0 fs/dcache.c:911
 do_renameat2+0x602/0xa10 fs/namei.c:5280
 __do_sys_rename fs/namei.c:5325 [inline]
 __se_sys_rename fs/namei.c:5323 [inline]
 __x64_sys_rename+0x58/0x70 fs/namei.c:5323
 x64_sys_call+0x1f9/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:83
 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 3306 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:778 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:872
 lru_add_drain_all+0x10/0x20 mm/swap.c:888
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1339
 generic_shutdown_super+0xe3/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1766
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1378
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1385
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x19 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3306 Comm: syz-executor Not tainted 6.17.0-rc1-syzkaller-00038-g0cc53520e68b #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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