EXT4-fs (loop4): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru

write to 0xffff888237c26b30 of 8 bytes by task 3318 on cpu 0:
 __invalidate_bh_lrus fs/buffer.c:1499 [inline]
 invalidate_bh_lru+0x8b/0xf0 fs/buffer.c:1511
 csd_do_func kernel/smp.c:134 [inline]
 smp_call_function_many_cond+0x5b0/0xbc0 kernel/smp.c:876
 on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
 invalidate_bdev+0x42/0x70 block/bdev.c:100
 ext4_put_super+0x65b/0x910 fs/ext4/super.c:1343
 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:7393
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x26e/0x2e0 fs/namespace.c:1435
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1442
 task_work_run+0x13c/0x1b0 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/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26b30 of 8 bytes by task 3314 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 smp_call_function_many_cond+0x30a/0xbc0 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
 invalidate_bdev+0x42/0x70 block/bdev.c:100
 ext4_put_super+0x65b/0x910 fs/ext4/super.c:1343
 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:7393
 deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
 deactivate_super+0x9f/0xb0 fs/super.c:506
 cleanup_mnt+0x26e/0x2e0 fs/namespace.c:1435
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1442
 task_work_run+0x13c/0x1b0 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/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888105ac0068 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3314 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-00325-g7cdabafc0012 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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