KCSAN: data-race in tick_nohz_stop_tick / tick_nohz_stop_tick (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a349e4c6 Merge tag 'xfs-5.10-fixes-7' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11357699500000
kernel config: https://syzkaller.appspot.com/x/.config?x=89a86a84f1254241
dashboard link: https://syzkaller.appspot.com/bug?extid=23a256029191772c2f02
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [fwei...@gmail.com linux-...@vger.kernel.org mi...@kernel.org tg...@linutronix.de]

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+23a256...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in tick_nohz_stop_tick / tick_nohz_stop_tick

write to 0xffffffff86fc1990 of 4 bytes by task 0 on cpu 1:
tick_nohz_stop_tick+0x99/0x410 kernel/time/tick-sched.c:789
__tick_nohz_idle_stop_tick kernel/time/tick-sched.c:981 [inline]
tick_nohz_idle_stop_tick+0x148/0x2e0 kernel/time/tick-sched.c:1002
cpuidle_idle_call kernel/sched/idle.c:209 [inline]
do_idle+0x176/0x230 kernel/sched/idle.c:273
cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffffffff86fc1990 of 4 bytes by task 0 on cpu 0:
tick_nohz_stop_tick+0x73/0x410 kernel/time/tick-sched.c:788
__tick_nohz_idle_stop_tick kernel/time/tick-sched.c:981 [inline]
tick_nohz_idle_stop_tick+0x148/0x2e0 kernel/time/tick-sched.c:1002
cpuidle_idle_call kernel/sched/idle.c:209 [inline]
do_idle+0x176/0x230 kernel/sched/idle.c:273
cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
rest_init+0xd7/0xe0 init/main.c:721
arch_call_rest_init+0xa/0xb
start_kernel+0x5a0/0x625 init/main.c:1061
secondary_startup_64_no_verify+0xb0/0xbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

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