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BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick

read-write to 0xffff8881000670a8 of 8 bytes by interrupt on cpu 1:
 wq_worker_tick+0x66/0x3c0 kernel/workqueue.c:1339
 scheduler_tick+0x13e/0x1d0 kernel/sched/core.c:5690
 update_process_times+0xf5/0x110 kernel/time/timer.c:2092
 tick_sched_handle kernel/time/tick-sched.c:255 [inline]
 tick_nohz_highres_handler+0x244/0x2c0 kernel/time/tick-sched.c:1519
 __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:1065 [inline]
 __sysvec_apic_timer_interrupt+0x52/0x190 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
 preempt_count arch/x86/include/asm/preempt.h:26 [inline]
 check_kcov_mode kernel/kcov.c:173 [inline]
 __sanitizer_cov_trace_pc+0x17/0x60 kernel/kcov.c:207
 n_tty_receive_buf_standard+0x4a7/0x2e20 drivers/tty/n_tty.c:1578
 __receive_buf drivers/tty/n_tty.c:1630 [inline]
 n_tty_receive_buf_common+0x7e5/0xbc0 drivers/tty/n_tty.c:1729
 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1775
 tty_ldisc_receive_buf+0x60/0xe0 drivers/tty/tty_buffer.c:386
 tty_port_default_receive_buf+0x59/0x90 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:444 [inline]
 flush_to_ldisc+0x1ca/0x400 drivers/tty/tty_buffer.c:494
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
 worker_thread+0x525/0x730 kernel/workqueue.c:2787
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read-write to 0xffff8881000670a8 of 8 bytes by interrupt on cpu 0:
 wq_worker_tick+0x66/0x3c0 kernel/workqueue.c:1339
 scheduler_tick+0x13e/0x1d0 kernel/sched/core.c:5690
 update_process_times+0xf5/0x110 kernel/time/timer.c:2092
 tick_sched_handle kernel/time/tick-sched.c:255 [inline]
 tick_nohz_highres_handler+0x244/0x2c0 kernel/time/tick-sched.c:1519
 __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:1065 [inline]
 __sysvec_apic_timer_interrupt+0x52/0x190 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
 arch_test_and_set_bit arch/x86/include/asm/bitops.h:137 [inline]
 test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
 queue_work_on+0xbe/0xf0 kernel/workqueue.c:1836
 queue_work include/linux/workqueue.h:548 [inline]
 tty_insert_flip_string_and_push_buffer+0x1d2/0x200 drivers/tty/tty_buffer.c:563
 pty_write+0x7e/0xa0 drivers/tty/pty.c:118
 tty_put_char+0x83/0xb0 drivers/tty/tty_io.c:3161
 n_tty_process_echo_ops drivers/tty/n_tty.c:664 [inline]
 __process_echoes+0x3a3/0x6a0 drivers/tty/n_tty.c:709
 flush_echoes drivers/tty/n_tty.c:807 [inline]
 __receive_buf drivers/tty/n_tty.c:1632 [inline]
 n_tty_receive_buf_common+0x8e6/0xbc0 drivers/tty/n_tty.c:1729
 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1775
 tty_ldisc_receive_buf+0x60/0xe0 drivers/tty/tty_buffer.c:386
 tty_port_default_receive_buf+0x59/0x90 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:444 [inline]
 flush_to_ldisc+0x1ca/0x400 drivers/tty/tty_buffer.c:494
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
 worker_thread+0x525/0x730 kernel/workqueue.c:2787
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0x000000000059b8c0 -> 0x000000000059dfd0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 54 Comm: kworker/u4:4 Not tainted 6.7.0-syzkaller-11091-g296455ade1fd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: events_unbound flush_to_ldisc
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