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BUG: KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt

write to 0xffff88811b106a48 of 8 bytes by interrupt on cpu 0:
 ps2_interrupt+0x50d/0x550 drivers/input/serio/libps2.c:-1
 serio_interrupt+0x66/0xf0 drivers/input/serio/serio.c:967
 i8042_handle_data+0x388/0x680 drivers/input/serio/i8042.c:598
 i8042_interrupt+0x15/0x90 drivers/input/serio/i8042.c:605
 __handle_irq_event_percpu+0x8b/0x480 kernel/irq/handle.c:209
 handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:263
 handle_edge_irq+0x155/0x440 kernel/irq/chip.c:859
 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline]
 handle_irq arch/x86/kernel/irq.c:209 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:280
 common_interrupt+0x3e/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 __sanitizer_cov_trace_cmp8+0x0/0xa0 kernel/kcov.c:285
 pie_calculate_probability+0x2f3/0x4c0 net/sched/sch_pie.c:392
 fq_pie_timer+0xf6/0x1d0 net/sched/sch_fq_pie.c:403
 call_timer_fn+0x36/0x250 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x40c/0x5f0 kernel/time/timer.c:2386
 run_timer_base kernel/time/timer.c:2395 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2405
 handle_softirqs+0xcc/0x2a0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x44/0xe0 kernel/softirq.c:758
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 preempt_count arch/x86/include/asm/preempt.h:37 [inline]
 get_ctx kernel/kcsan/core.c:206 [inline]
 check_access kernel/kcsan/core.c:758 [inline]
 __tsan_read8+0xbf/0x190 kernel/kcsan/core.c:1033
 do_anonymous_page mm/memory.c:5452 [inline]
 do_pte_missing mm/memory.c:4698 [inline]
 handle_pte_fault mm/memory.c:6558 [inline]
 __handle_mm_fault mm/memory.c:6707 [inline]
 handle_mm_fault+0x1975/0x3bb0 mm/memory.c:6876
 do_user_addr_fault+0x636/0x1060 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

read to 0xffff88811b106a48 of 8 bytes by task 5223 on cpu 1:
 ps2_do_sendbyte+0x10b/0x320 drivers/input/serio/libps2.c:65
 __ps2_command+0x364/0xaa0 drivers/input/serio/libps2.c:322
 ps2_command+0x52/0x90 drivers/input/serio/libps2.c:403
 thinking_detect+0x6a/0x270 drivers/input/mouse/psmouse-base.c:660
 psmouse_do_detect drivers/input/mouse/psmouse-base.c:995 [inline]
 psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1009 [inline]
 psmouse_extensions+0x1df/0x960 drivers/input/mouse/psmouse-base.c:1078
 psmouse_switch_protocol+0x8b/0x300 drivers/input/mouse/psmouse-base.c:1513
 psmouse_connect+0x5a3/0xb60 drivers/input/mouse/psmouse-base.c:1602
 serio_connect_driver drivers/input/serio/serio.c:44 [inline]
 serio_driver_probe+0x54/0x70 drivers/input/serio/serio.c:748
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x1ba/0x600 drivers/base/dd.c:706
 __driver_probe_device+0x14f/0x1c0 drivers/base/dd.c:868
 driver_probe_device+0x37/0x2f0 drivers/base/dd.c:898
 __device_attach_driver+0x227/0x330 drivers/base/dd.c:1026
 bus_for_each_drv+0x1c0/0x230 drivers/base/bus.c:500
 __device_attach+0x1d1/0x2a0 drivers/base/dd.c:1098
 device_attach+0x17/0x20 drivers/base/dd.c:1141
 serio_find_driver drivers/input/serio/serio.c:112 [inline]
 drvctl_store+0x7ba/0xc20 drivers/input/serio/serio.c:367
 dev_attr_store+0x4a/0x70 drivers/base/core.c:2509
 sysfs_kf_write+0xfe/0x120 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x1d2/0x2e0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57f/0x9a0 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5223 Comm: syz.2.526 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input95