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KCSAN: data-race in print_cpu / tick_nohz_idle_enter (7)

Status: auto-obsoleted due to no activity on 2023/10/05 16:08
Subsystems: kernel
[Documentation on labels]
First crash: 245d, last: 245d
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 (4) kernel 3 631d 639d 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 71d 71d 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 678d 678d 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 472d 472d 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 387d 387d 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 953d 953d 0/26 auto-closed as invalid on 2021/10/28 01:37
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (2) kernel 2 883d 907d 0/26 auto-closed as invalid on 2022/01/05 10:03
upstream KCSAN: data-race in print_cpu / tick_nohz_idle_enter (9) kernel 1 35d 35d 0/26 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 0xffff888237c1f368 of 8 bytes by task 0 on cpu 0:
 tick_nohz_start_idle kernel/time/tick-sched.c:686 [inline]
 tick_nohz_idle_enter+0x85/0xd0 kernel/time/tick-sched.c:1172
 do_idle+0x3c/0x230 kernel/sched/idle.c:256
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 rest_init+0xf3/0x100 init/main.c:726
 arch_call_rest_init+0x9/0x10 init/main.c:823
 start_kernel+0x57d/0x5d0 init/main.c:1068
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:556
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:537
 secondary_startup_64_no_verify+0x167/0x16b

read to 0xffff888237c1f368 of 8 bytes by task 4847 on cpu 1:
 print_cpu+0x4c4/0x640 kernel/time/timer_list.c:158
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:291
 seq_read_iter+0x612/0x8f0 fs/seq_file.c:272
 proc_reg_read_iter+0x114/0x180 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:1979 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:364
 vfs_splice_read fs/splice.c:993 [inline]
 splice_direct_to_actor+0x28c/0x690 fs/splice.c:1069
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000001c1e119f04 -> 0x0000001c1e149543

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4847 Comm: syz-executor.4 Not tainted 6.5.0-syzkaller-08894-gb97d64c72259 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/31 16:04 upstream b97d64c72259 84803932 .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.