syzbot


KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter (4)

Status: auto-closed as invalid on 2022/03/09 00:14
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 407d, last: 307d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter (5) 2 221d 247d 0/24 auto-closed as invalid on 2022/06/02 15:56
upstream KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter 10 922d 1045d 0/24 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter (3) 10 776d 833d 0/24 auto-closed as invalid on 2020/11/24 16:04
upstream KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter (2) 2 884d 897d 0/24 auto-closed as invalid on 2020/08/09 00:56
upstream KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter (6) 1 142d 142d 0/24 auto-closed as invalid on 2022/08/21 13:12

Sample crash report:
==================================================================
BUG: KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter

write to 0xffff888237c1e0b4 of 1 bytes by task 0 on cpu 0:
 tick_nohz_idle_enter+0x72/0xc0 kernel/time/tick-sched.c:1113
 do_idle+0x3d/0x250 kernel/sched/idle.c:280
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 rest_init+0xfa/0x100 init/main.c:725
 arch_call_rest_init+0xa/0xb init/main.c:881
 start_kernel+0x5e4/0x669 init/main.c:1138
 secondary_startup_64_no_verify+0xc4/0xcb

read to 0xffff888237c1e0b4 of 1 bytes by task 15234 on cpu 1:
 get_cpu_idle_time_us+0x6b/0x1f0
 get_idle_time fs/proc/stat.c:54 [inline]
 show_stat+0x2ef/0xdd0 fs/proc/stat.c:134
 seq_read_iter+0x2e1/0x930 fs/seq_file.c:230
 proc_reg_read_iter+0xd6/0x170 fs/proc/inode.c:296
 call_read_iter include/linux/fs.h:2068 [inline]
 io_iter_do_read fs/io_uring.c:3611 [inline]
 io_read fs/io_uring.c:3668 [inline]
 io_issue_sqe+0xb2e/0x98d0 fs/io_uring.c:6751
 __io_queue_sqe+0x20/0x6a0 fs/io_uring.c:7098
 io_queue_sqe+0x46/0x550 fs/io_uring.c:7140
 io_submit_sqe+0x796/0x4b34 fs/io_uring.c:7348
 io_submit_sqes+0x25f/0x560 fs/io_uring.c:7454
 __do_sys_io_uring_enter fs/io_uring.c:10154 [inline]
 __se_sys_io_uring_enter+0x212/0xb00 fs/io_uring.c:10096
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:10096
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15234 Comm: syz-executor.3 Tainted: G        W         5.17.0-rc2-syzkaller-00039-g9f7fb8de5d9b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (14):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/02/02 00:05 upstream 9f7fb8de5d9b 4ebb2798 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2022/01/28 16:33 upstream 23a46422c561 495e00c5 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/26 09:59 upstream 438645193e59 e4f103c4 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/25 01:45 upstream b927dfc67d05 6caa12e4 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/23 18:53 upstream 996a18eb796a 6caa12e4 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/22 10:08 upstream 2f47a9a4dfa3 6caa12e4 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/21 20:58 upstream 1c3e979bf3e2 6caa12e4 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/12/20 08:40 upstream a7904a538933 021b36cb .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/11/29 07:19 upstream d06c942efea4 63eeac02 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/11/09 10:52 upstream e851dfae4371 8ab17e57 .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/11/06 06:10 upstream fe91c4725aee 4c1be0be .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/11/04 16:26 upstream 7ddb58cb0eca 4c1be0be .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/10/29 07:56 upstream f25a5481af12 2353a3ec .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
ci2-upstream-kcsan-gce 2021/10/24 23:42 upstream 6c62666d8879 4f0000ee .config log report info KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter
* Struck through repros no longer work on HEAD.