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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:5672
 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:1063 [inline]
 __sysvec_apic_timer_interrupt+0x52/0x190 arch/x86/kernel/apic/apic.c:1080
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1074
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 n_tty_receive_buf_common+0x277/0xbd0
 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:388
 ret_from_fork+0x48/0x60 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:5672
 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:1063 [inline]
 __sysvec_apic_timer_interrupt+0x52/0x190 arch/x86/kernel/apic/apic.c:1080
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1074
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 decode_watchpoint kernel/kcsan/encoding.h:74 [inline]
 find_watchpoint kernel/kcsan/core.c:132 [inline]
 check_access kernel/kcsan/core.c:737 [inline]
 __tsan_unaligned_write8+0x44/0x180 kernel/kcsan/core.c:1025
 commit_echoes drivers/tty/n_tty.c:767 [inline]
 n_tty_receive_char+0x4be/0x670 drivers/tty/n_tty.c:1419
 n_tty_receive_buf_standard+0x484/0x2d40 drivers/tty/n_tty.c:1588
 __receive_buf drivers/tty/n_tty.c:1612 [inline]
 n_tty_receive_buf_common+0x84c/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:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x000000002c38f410 -> 0x000000002c391b20

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 293 Comm: kworker/u4:4 Tainted: G        W          6.5.0-syzkaller-08262-gef2a0b7cdbc5 #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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