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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 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:1689 [inline]
 __hrtimer_run_queues+0x210/0x5d0 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x20d/0x7b0 kernel/time/hrtimer.c:1815
 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+0x6a/0x80 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
 __sanitizer_cov_trace_switch+0x7e/0x110 kernel/kcov.c:340
 do_output_char+0x4e/0x4f0 drivers/tty/n_tty.c:420
 __process_echoes+0x212/0x6a0 drivers/tty/n_tty.c:717
 process_echoes drivers/tty/n_tty.c:789 [inline]
 n_tty_receive_char_flow_ctrl+0x124/0x190 drivers/tty/n_tty.c:1249
 n_tty_receive_char_special drivers/tty/n_tty.c:1359 [inline]
 n_tty_receive_buf_standard+0x4e1/0x2e20 drivers/tty/n_tty.c:1604
 __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+0x5b8/0xa40 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 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:1689 [inline]
 __hrtimer_run_queues+0x210/0x5d0 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x20d/0x7b0 kernel/time/hrtimer.c:1815
 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+0x6a/0x80 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:15 [inline]
 raw_atomic64_read include/linux/atomic/atomic-arch-fallback.h:2569 [inline]
 raw_atomic_long_read include/linux/atomic/atomic-long.h:38 [inline]
 atomic_long_read include/linux/atomic/atomic-instrumented.h:3161 [inline]
 find_watchpoint kernel/kcsan/core.c:131 [inline]
 check_access kernel/kcsan/core.c:737 [inline]
 __tsan_read8+0x4a/0x180 kernel/kcsan/core.c:1025
 __process_echoes+0x5e/0x6a0 drivers/tty/n_tty.c:706
 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+0x5b8/0xa40 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: 0x0000000002915940 -> 0x0000000002918050

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5111 Comm: kworker/u4:9 Not tainted 6.8.0-rc5-syzkaller-00278-g603c04e27c3e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: events_unbound flush_to_ldisc
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