KCSAN: data-race in ps2_do_sendbyte / ps2_handle_ack (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c84e1efa Merge tag 'asm-generic-fixes-5.10-2' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=121513dd500000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9b19d1bde60f8d
dashboard link: https://syzkaller.appspot.com/bug?extid=85537422410fcb98abbd
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [dmitry....@gmail.com gusta...@kernel.org linux...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+855374...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in ps2_do_sendbyte / ps2_handle_ack

read-write to 0xffff88810375d040 of 8 bytes by interrupt on cpu 0:
ps2_handle_ack+0x147/0x340 drivers/input/serio/libps2.c:439
atkbd_interrupt+0xbe2/0xcc0 drivers/input/keyboard/atkbd.c:434
serio_interrupt+0x5d/0xe0 drivers/input/serio/serio.c:1002
i8042_interrupt+0x39e/0x720 drivers/input/serio/i8042.c:602
__handle_irq_event_percpu+0x93/0x450 kernel/irq/handle.c:156
handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
handle_irq_event+0x81/0x120 kernel/irq/handle.c:213
handle_edge_irq+0x16e/0x590 kernel/irq/chip.c:819
asm_call_irq_on_stack+0xf/0x20
__run_irq_on_irqstack arch/x86/include/asm/irq_stack.h:48 [inline]
run_irq_on_irqstack_cond arch/x86/include/asm/irq_stack.h:101 [inline]
handle_irq arch/x86/kernel/irq.c:230 [inline]
__common_interrupt arch/x86/kernel/irq.c:249 [inline]
common_interrupt+0x8e/0x130 arch/x86/kernel/irq.c:239
asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:622
decode_watchpoint kernel/kcsan/encoding.h:67 [inline]
find_watchpoint kernel/kcsan/core.c:124 [inline]
check_access kernel/kcsan/core.c:616 [inline]
__tsan_read_write4+0x3c/0x180 kernel/kcsan/core.c:841
rcu_preempt_read_exit kernel/rcu/tree_plugin.h:361 [inline]
__rcu_read_unlock+0x3a/0x220 kernel/rcu/tree_plugin.h:396
rcu_read_unlock include/linux/rcupdate.h:694 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline]
batadv_nc_worker+0xea/0xa10 net/batman-adv/network-coding.c:718
process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
worker_thread+0x635/0xb90 kernel/workqueue.c:2418
kthread+0x1fd/0x220 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff88810375d040 of 8 bytes by task 9843 on cpu 1:
ps2_do_sendbyte+0x1a1/0x370 drivers/input/serio/libps2.c:45
__ps2_command+0x30d/0x990 drivers/input/serio/libps2.c:273
ps2_command+0x51/0x90 drivers/input/serio/libps2.c:332
atkbd_set_repeat_rate drivers/input/keyboard/atkbd.c:595 [inline]
atkbd_event_work+0x2c5/0x300 drivers/input/keyboard/atkbd.c:649
process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
worker_thread+0x635/0xb90 kernel/workqueue.c:2418
kthread+0x1fd/0x220 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9843 Comm: kworker/1:5 Not tainted 5.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events atkbd_event_work
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.