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BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru

write to 0xffff888237c2a388 of 8 bytes by task 3087 on cpu 0:
 __invalidate_bh_lrus fs/buffer.c:1493 [inline]
 invalidate_bh_lru+0x88/0xf0 fs/buffer.c:1505
 csd_do_func kernel/smp.c:131 [inline]
 smp_call_function_many_cond+0x697/0xc20 kernel/smp.c:826
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1003
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1524
 invalidate_bdev+0x55/0x80 block/bdev.c:85
 ext4_put_super+0x502/0x7f0 fs/ext4/super.c:1340
 generic_shutdown_super+0xd9/0x260 fs/super.c:499
 kill_block_super+0x3b/0x60 fs/super.c:1417
 deactivate_locked_super+0x6b/0xd0 fs/super.c:330
 deactivate_super+0x9b/0xb0 fs/super.c:361
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd1/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888237c2a388 of 8 bytes by task 29736 on cpu 1:
 has_bh_in_lru+0x35/0x1e0 fs/buffer.c:1515
 smp_call_function_many_cond+0x2e4/0xc20 kernel/smp.c:788
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1003
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1524
 invalidate_bdev+0x55/0x80 block/bdev.c:85
 invalidate_disk+0x29/0x80 block/genhd.c:734
 __loop_clr_fd+0x169/0x3b0 drivers/block/loop.c:1164
 loop_clr_fd drivers/block/loop.c:1257 [inline]
 lo_ioctl+0xe93/0x12e0 drivers/block/loop.c:1563
 blkdev_ioctl+0x375/0x460 block/ioctl.c:621
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff888109c9fdd0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29736 Comm: syz-executor.1 Not tainted 6.4.0-syzkaller-12274-g5133c9e51de4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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