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BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru

read-write to 0xffff888237d2ba28 of 8 bytes by task 11695 on cpu 1:
 bh_lru_install fs/buffer.c:1337 [inline]
 __find_get_block+0x42e/0x890 fs/buffer.c:1400
 bdev_getblk+0x30/0x3b0 fs/buffer.c:1425
 __bread_gfp+0x52/0x280 fs/buffer.c:1485
 sb_bread include/linux/buffer_head.h:346 [inline]
 fat_set_state+0xd4/0x1e0 fs/fat/inode.c:687
 fat_put_super+0x2e/0x80 fs/fat/inode.c:735
 generic_shutdown_super+0xe5/0x220 fs/super.c:642
 kill_block_super+0x2a/0x70 fs/super.c:1710
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1420
 task_work_run+0x13a/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d2ba28 of 8 bytes by task 3306 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x23f/0x3f0 mm/swap.c:867
 lru_add_drain_all+0x10/0x20 mm/swap.c:883
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x571/0x810 fs/ext4/super.c:1356
 generic_shutdown_super+0xe5/0x220 fs/super.c:642
 kill_block_super+0x2a/0x70 fs/super.c:1710
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7368
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1420
 task_work_run+0x13a/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff888106247478

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3306 Comm: syz-executor Not tainted 6.14.0-rc6-syzkaller-00022-gb7f94fcf5546 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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