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BUG: KCSAN: assert: race in __block_task kernel/sched/sched.h:2773 [inline]
BUG: KCSAN: assert: race in dequeue_entities+0x6df/0x760 kernel/sched/fair.c:7180

race at unknown origin, with assert no writes to 0xffff8881036da168 of 4 bytes by task 11888 on cpu 1:
 __block_task kernel/sched/sched.h:2773 [inline]
 dequeue_entities+0x6df/0x760 kernel/sched/fair.c:7180
 pick_next_entity kernel/sched/fair.c:5627 [inline]
 pick_task_fair kernel/sched/fair.c:8859 [inline]
 pick_next_task_fair+0x7d/0x410 kernel/sched/fair.c:8879
 __pick_next_task kernel/sched/core.c:5968 [inline]
 pick_next_task kernel/sched/core.c:6490 [inline]
 __schedule+0x284/0x940 kernel/sched/core.c:6644
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x55/0xc0 kernel/sched/core.c:6782
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:6839
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x36d/0x8e0 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xa/0x10 kernel/locking/mutex.c:1040
 mutex_lock+0x2d/0x40 kernel/locking/mutex.c:286
 exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 synchronize_rcu_expedited+0x18b/0x7a0 kernel/rcu/tree_exp.h:976
 namespace_unlock+0x17b/0x2c0 fs/namespace.c:1703
 do_umount fs/namespace.c:1931 [inline]
 path_umount+0x9bc/0xa10 fs/namespace.c:2013
 ksys_umount fs/namespace.c:2036 [inline]
 __do_sys_umount fs/namespace.c:2041 [inline]
 __se_sys_umount fs/namespace.c:2039 [inline]
 __x64_sys_umount+0xb6/0xe0 fs/namespace.c:2039
 x64_sys_call+0x2599/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:167
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11888 Comm: syz-executor Not tainted 6.12.0-rc5-syzkaller-00063-g0fc810ae3ae1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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