syzbot


KCSAN: data-race in print_cpu / tick_nohz_idle_enter (10)

Status: moderation: reported on 2024/05/11 22:38
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+dbec1d508021c2bd1bfd@syzkaller.appspotmail.com
First crash: 34d, last: 3d08h
Similar bugs (9)
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 288d 288d 0/27 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 674d 682d 0/27 auto-closed as invalid on 2022/09/15 04:11
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (8) kernel 1 114d 114d 0/27 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 721d 721d 0/27 auto-closed as invalid on 2022/07/29 11:15
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (5) kernel 1 515d 515d 0/27 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 430d 430d 0/27 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 996d 996d 0/27 auto-closed as invalid on 2021/10/28 01:37
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (2) kernel 2 926d 950d 0/27 auto-closed as invalid on 2022/01/05 10:03
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (9) kernel 1 78d 78d 0/27 auto-obsoleted due to no activity on 2024/05/02 11:27

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

write to 0xffff888237c20538 of 8 bytes by task 0 on cpu 0:
 tick_nohz_start_idle kernel/time/tick-sched.c:750 [inline]
 tick_nohz_idle_enter+0x89/0xe0 kernel/time/tick-sched.c:1263
 do_idle+0x3d/0x230 kernel/sched/idle.c:277
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
 rest_init+0xef/0xf0 init/main.c:747
 start_kernel+0x581/0x5e0 init/main.c:1103
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x12c/0x137

read to 0xffff888237c20538 of 8 bytes by task 7541 on cpu 1:
 print_cpu+0x4ed/0x670 kernel/time/timer_list.c:162
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:295
 traverse+0x155/0x3c0 fs/seq_file.c:111
 seq_read_iter+0x85a/0x940 fs/seq_file.c:195
 proc_reg_read_iter+0x11e/0x190 fs/proc/inode.c:299
 copy_splice_read+0x3a4/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x960 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000001b7c3bee62 -> 0x0000001b7c3c679f


Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/11 19:47 upstream 83a7eefedc9b 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/06/08 23:40 upstream dc772f8237f9 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/06/01 04:37 upstream d8ec19857b09 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/05/29 09:55 upstream e0cce98fe279 34889ee3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/05/25 08:28 upstream 56fb6f92854f a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/05/25 04:52 upstream 02c438bbfffe a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
2024/05/11 22:37 upstream cf87f46fd34d 9026e142 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_idle_enter
* Struck through repros no longer work on HEAD.