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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff8881000660a8 of 8 bytes by interrupt on cpu 0:
 wq_worker_tick+0x63/0x2c0 kernel/workqueue.c:1146
 scheduler_tick+0x13e/0x1d0 kernel/sched/core.c:5674
 update_process_times+0xf5/0x110 kernel/time/timer.c:2076
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x244/0x2c0 kernel/time/tick-sched.c:1492
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x217/0x700 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x20d/0x7b0 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline]
 __sysvec_apic_timer_interrupt+0x73/0x210 arch/x86/kernel/apic/apic.c:1115
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1109
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x2f/0x40 kernel/locking/spinlock.c:202
 process_one_work+0x3f7/0x860 kernel/workqueue.c:2572
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

read-write to 0xffff8881000660a8 of 8 bytes by interrupt on cpu 1:
 wq_worker_tick+0x63/0x2c0 kernel/workqueue.c:1146
 scheduler_tick+0x13e/0x1d0 kernel/sched/core.c:5674
 update_process_times+0xf5/0x110 kernel/time/timer.c:2076
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x244/0x2c0 kernel/time/tick-sched.c:1492
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x217/0x700 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x20d/0x7b0 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline]
 __sysvec_apic_timer_interrupt+0x73/0x210 arch/x86/kernel/apic/apic.c:1115
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1109
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 arch_test_and_set_bit arch/x86/include/asm/bitops.h:138 [inline]
 test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
 queue_work_on+0xbe/0xf0 kernel/workqueue.c:1746
 queue_work include/linux/workqueue.h:506 [inline]
 tty_insert_flip_string_and_push_buffer+0x1e9/0x210 drivers/tty/tty_buffer.c:634
 pty_write+0x83/0xa0 drivers/tty/pty.c:118
 tty_put_char+0x83/0xb0 drivers/tty/tty_io.c:3151
 __process_echoes+0x3a5/0x620 drivers/tty/n_tty.c:716
 flush_echoes drivers/tty/n_tty.c:816 [inline]
 __receive_buf drivers/tty/n_tty.c:1614 [inline]
 n_tty_receive_buf_common+0x8f9/0xbd0 drivers/tty/n_tty.c:1710
 n_tty_receive_buf2+0x32/0x40 drivers/tty/n_tty.c:1756
 tty_ldisc_receive_buf+0x60/0xe0 drivers/tty/tty_buffer.c:457
 tty_port_default_receive_buf+0x58/0x80 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:515 [inline]
 flush_to_ldisc+0x1ca/0x400 drivers/tty/tty_buffer.c:565
 process_one_work+0x434/0x860 kernel/workqueue.c:2600
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x00000000000ef420 -> 0x00000000000f1b30

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3099 Comm: kworker/u4:5 Not tainted 6.5.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: events_unbound flush_to_ldisc
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