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BUG: KCSAN: data-race in cypress_send_ext_cmd / psmouse_interrupt

write to 0xffff8881003b5ae1 of 1 bytes by interrupt on cpu 0:
 psmouse_interrupt+0x33c/0x930 drivers/input/mouse/psmouse-base.c:387
 serio_interrupt+0x5d/0xe0 drivers/input/serio/serio.c:1002
 i8042_interrupt+0x39e/0x720 drivers/input/serio/i8042.c:602
 __handle_irq_event_percpu+0x93/0x3f0 kernel/irq/handle.c:156
 handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
 handle_irq_event+0xb0/0x160 kernel/irq/handle.c:213
 handle_edge_irq+0x17e/0x600 kernel/irq/chip.c:819
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq arch/x86/kernel/irq.c:231 [inline]
 __common_interrupt+0x38/0xb0 arch/x86/kernel/irq.c:250
 common_interrupt+0x73/0x90 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:638
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:838 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
 find_watchpoint kernel/kcsan/core.c:127 [inline]
 check_access kernel/kcsan/core.c:627 [inline]
 __tsan_read8+0x24/0x180 kernel/kcsan/core.c:864
 __d_lookup_rcu+0x235/0x3e0 fs/dcache.c:2341
 lookup_fast+0xae/0x350 fs/namei.c:1552
 walk_component+0x5c/0x350 fs/namei.c:1938
 link_path_walk+0x4ba/0x780 fs/namei.c:2265
 path_lookupat+0x7b/0x570 fs/namei.c:2420
 filename_lookup+0xff/0x390 fs/namei.c:2454
 user_path_at_empty+0x3b/0x50 fs/namei.c:2734
 user_path_at include/linux/namei.h:60 [inline]
 vfs_statx+0x98/0x290 fs/stat.c:203
 vfs_fstatat fs/stat.c:225 [inline]
 vfs_lstat include/linux/fs.h:3384 [inline]
 __do_sys_newlstat fs/stat.c:380 [inline]
 __se_sys_newlstat+0x46/0x250 fs/stat.c:374
 __x64_sys_newlstat+0x2d/0x40 fs/stat.c:374
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881003b5ae1 of 1 bytes by task 7213 on cpu 1:
 cypress_ps2_read_cmd_status drivers/input/mouse/cypress_ps2.c:120 [inline]
 cypress_send_ext_cmd+0x1f2/0x490 drivers/input/mouse/cypress_ps2.c:189
 cypress_detect+0x32/0x100 drivers/input/mouse/cypress_ps2.c:205
 psmouse_do_detect drivers/input/mouse/psmouse-base.c:1009 [inline]
 psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1023 [inline]
 psmouse_extensions+0xa03/0x1790 drivers/input/mouse/psmouse-base.c:1146
 __psmouse_reconnect+0x31e/0x620 drivers/input/mouse/psmouse-base.c:1728
 psmouse_reconnect+0x13/0x20 drivers/input/mouse/psmouse-base.c:1766
 serio_reconnect_driver drivers/input/serio/serio.c:59 [inline]
 serio_reconnect_port drivers/input/serio/serio.c:588 [inline]
 serio_handle_event+0x6be/0xc20 drivers/input/serio/serio.c:214
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276
 worker_thread+0x636/0xae0 kernel/workqueue.c:2422
 kthread+0x1d0/0x1f0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

value changed: 0x00 -> 0x03

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7213 Comm: kworker/1:4 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_long serio_handle_event
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