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KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 1543d, last: 1424d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter (2) kernel 8 1268d 1233d 0/26 auto-closed as invalid on 2020/12/21 11:40
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter (3) kernel 1 962d 962d 0/26 auto-closed as invalid on 2021/10/09 06:41
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter (6) kernel 3 495d 497d 0/26 auto-obsoleted due to no activity on 2023/04/06 19:58
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter (5) kernel 1 706d 706d 0/26 auto-closed as invalid on 2022/06/22 15:45
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_nohz_idle_enter (4) kernel 12 803d 905d 0/26 auto-closed as invalid on 2022/03/17 13:24

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

write to 0xffff88812c02030c of 1 bytes by task 0 on cpu 0:
 tick_nohz_idle_enter+0x8f/0x100 kernel/time/tick-sched.c:1024
 do_idle+0x38/0x290 kernel/sched/idle.c:244
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361
 rest_init+0xe4/0xeb init/main.c:667
 arch_call_rest_init+0x13/0x2b
 start_kernel+0x7fe/0x823 init/main.c:1005
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

read to 0xffff88812c02030c of 1 bytes by task 13097 on cpu 1:
 get_cpu_iowait_time_us+0xe5/0x170 kernel/time/tick-sched.c:637
 get_iowait_time.isra.0+0x65/0x90 fs/proc/stat.c:69
 show_stat+0x633/0xa50 fs/proc/stat.c:173
 seq_read+0x2ef/0x940 fs/seq_file.c:206
 pde_read fs/proc/inode.c:292 [inline]
 proc_reg_read+0xb3/0x1b0 fs/proc/inode.c:302
 do_loop_readv_writev fs/read_write.c:715 [inline]
 do_loop_readv_writev fs/read_write.c:702 [inline]
 do_iter_read+0x33f/0x3a0 fs/read_write.c:936
 vfs_readv+0x9c/0xf0 fs/read_write.c:1054
 do_preadv+0x129/0x1c0 fs/read_write.c:1146
 __do_sys_preadv fs/read_write.c:1196 [inline]
 __se_sys_preadv fs/read_write.c:1191 [inline]
 __x64_sys_preadv+0x5e/0x80 fs/read_write.c:1191
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13097 Comm: syz-executor.3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/30 06:36 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 954bd312 .config console log report ci2-upstream-kcsan-gce
2020/05/06 00:39 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 35b8eb30 .config console log report ci2-upstream-kcsan-gce
2020/04/19 05:45 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 365fba24 .config console log report ci2-upstream-kcsan-gce
2020/04/08 06:07 https://github.com/google/ktsan.git kcsan 40959e34d670 db9bcd4b .config console log report ci2-upstream-kcsan-gce
2020/03/12 13:51 https://github.com/google/ktsan.git kcsan 941e0d917bbf d850e9d0 .config console log report ci2-upstream-kcsan-gce
2020/02/23 02:27 https://github.com/google/ktsan.git kcsan 766d004d1b85 2c36e7a7 .config console log report ci2-upstream-kcsan-gce
2020/02/14 18:21 https://github.com/google/ktsan.git kcsan b12d66a6c34f 5d7b90f1 .config console log report ci2-upstream-kcsan-gce
2020/02/09 02:38 https://github.com/google/ktsan.git kcsan f60f0f543333 06150bf1 .config console log report ci2-upstream-kcsan-gce
2020/02/01 13:15 https://github.com/google/ktsan.git kcsan 245a43005292 326d4c78 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.