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KCSAN: data-race in print_cpu / tick_nohz_idle_enter (2)

Status: auto-closed as invalid on 2022/01/05 10:03
Subsystems: kernel
[Documentation on labels]
First crash: 895d, last: 870d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (7) kernel 1 232d 232d 0/26 auto-obsoleted due to no activity on 2023/10/05 16:08
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (4) kernel 3 618d 626d 0/26 auto-closed as invalid on 2022/09/15 04:11
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (8) kernel 1 58d 58d 0/26 auto-obsoleted due to no activity on 2024/03/27 09:49
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (3) kernel 1 665d 665d 0/26 auto-closed as invalid on 2022/07/29 11:15
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (5) kernel 1 459d 459d 0/26 auto-obsoleted due to no activity on 2023/02/27 15:47
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (6) kernel 1 374d 374d 0/26 auto-obsoleted due to no activity on 2023/05/16 12:25
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter kernel 1 940d 940d 0/26 auto-closed as invalid on 2021/10/28 01:37
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (9) kernel 1 22d 22d 0/26 moderation: reported on 2024/03/28 11:27

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

write to 0xffff888237c1defc 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
 start_kernel+0x5e4/0x669 init/main.c:1135
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff888237c1defc of 1 bytes by task 25322 on cpu 1:
 print_cpu+0x466/0x690 kernel/time/timer_list.c:154
 timer_list_show+0x114/0x180 kernel/time/timer_list.c:291
 seq_read_iter+0x2e1/0x930 fs/seq_file.c:230
 proc_reg_read_iter+0xfc/0x170 fs/proc/inode.c:300
 call_read_iter include/linux/fs.h:2156 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 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: 25322 Comm: syz-executor.0 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/01 09:59 upstream 58e1100fdc59 5fa3eacc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2021/11/07 04:55 upstream 512b7931ad05 4c1be0be .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
* Struck through repros no longer work on HEAD.