================================================================== BUG: KCSAN: data-race in insert_work / wq_worker_running read-write to 0xffff888237d2a820 of 4 bytes by task 1909 on cpu 1: wq_worker_running+0x96/0xe0 kernel/workqueue.c:880 schedule_timeout+0xc1/0x290 kernel/time/timer.c:1935 synchronize_rcu_expedited_wait_once kernel/rcu/tree_exp.h:571 [inline] synchronize_rcu_expedited_wait+0x22a/0xbf0 kernel/rcu/tree_exp.h:622 rcu_exp_wait_wake kernel/rcu/tree_exp.h:688 [inline] rcu_exp_sel_wait_wake+0x355/0x730 kernel/rcu/tree_exp.h:722 wait_rcu_exp_gp+0x1a/0x20 kernel/rcu/tree_exp.h:512 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 read to 0xffff888237d2a820 of 4 bytes by task 13921 on cpu 0: __need_more_worker kernel/workqueue.c:785 [inline] insert_work+0x10e/0x190 kernel/workqueue.c:1365 __queue_work+0x69e/0x8e0 kernel/workqueue.c:1517 queue_work_on+0x7e/0xe0 kernel/workqueue.c:1545 __lru_add_drain_all+0x2cf/0x3e0 mm/swap.c:835 lru_add_drain_all+0xc/0x10 mm/swap.c:849 invalidate_bdev+0x56/0x80 block/bdev.c:85 ext4_put_super+0x510/0x810 fs/ext4/super.c:1279 generic_shutdown_super+0xd5/0x240 fs/super.c:462 kill_block_super+0x4a/0x90 fs/super.c:1394 deactivate_locked_super+0x6a/0xb0 fs/super.c:332 deactivate_super+0x85/0x90 fs/super.c:363 cleanup_mnt+0x267/0x2d0 fs/namespace.c:1186 __cleanup_mnt+0x15/0x20 fs/namespace.c:1193 task_work_run+0x8e/0x110 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x124/0x130 kernel/entry/common.c:169 exit_to_user_mode_prepare kernel/entry/common.c:201 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:294 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00000000 -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 13921 Comm: syz-executor.1 Not tainted 5.19.0-syzkaller-10532-g9e2f40233670-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 ================================================================== EXT4-fs (loop1): unmounting filesystem. EXT4-fs (loop1): unmounting filesystem.