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BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru

read to 0xffff88812be27e00 of 8 bytes by task 8919 on cpu 1:
 has_bh_in_lru+0x44/0x90 fs/buffer.c:1387
 on_each_cpu_cond_mask+0xa3/0x150 kernel/smp.c:695
 on_each_cpu_cond+0x44/0x60 kernel/smp.c:721
 invalidate_bh_lrus+0x32/0x40 fs/buffer.c:1396
 kill_bdev+0x7f/0xb0 fs/block_dev.c:85
 __blkdev_put+0x138/0x420 fs/block_dev.c:1861
 blkdev_put+0x89/0x2f0 fs/block_dev.c:1929
 kill_block_super+0x90/0xb0 fs/super.c:1445
 deactivate_locked_super+0x64/0xb0 fs/super.c:335
 deactivate_super fs/super.c:366 [inline]
 deactivate_super+0xca/0xe0 fs/super.c:362
 cleanup_mnt+0x27f/0x330 fs/namespace.c:1102
 __cleanup_mnt+0x1f/0x30 fs/namespace.c:1109
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88812be27e00 of 8 bytes by task 8917 on cpu 0:
 invalidate_bh_lru+0x83/0xf0 fs/buffer.c:1376
 on_each_cpu_mask+0xfb/0x150 kernel/smp.c:649
 on_each_cpu_cond_mask+0xf7/0x150 kernel/smp.c:697
 on_each_cpu_cond+0x44/0x60 kernel/smp.c:721
 invalidate_bh_lrus+0x32/0x40 fs/buffer.c:1396
 kill_bdev+0x7f/0xb0 fs/block_dev.c:85
 __blkdev_put+0x138/0x420 fs/block_dev.c:1861
 blkdev_put+0x89/0x2f0 fs/block_dev.c:1929
 kill_block_super+0x90/0xb0 fs/super.c:1445
 deactivate_locked_super+0x64/0xb0 fs/super.c:335
 deactivate_super fs/super.c:366 [inline]
 deactivate_super+0xca/0xe0 fs/super.c:362
 cleanup_mnt+0x27f/0x330 fs/namespace.c:1102
 __cleanup_mnt+0x1f/0x30 fs/namespace.c:1109
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8917 Comm: syz-executor.3 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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