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KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_idle_stop_tick

Status: closed as invalid on 2019/10/15 15:50
Subsystems: kernel
[Documentation on labels]
First crash: 1665d, last: 1655d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_idle_stop_tick (4) kernel 65 33d 141d 0/26 moderation: reported on 2023/12/07 10:15
upstream KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_idle_stop_tick (2) kernel 26 1620d 1654d 0/26 closed as invalid on 2019/11/19 14:04
upstream KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_idle_stop_tick (3) kernel 109 1408d 1518d 0/26 auto-closed as invalid on 2020/07/22 23:43

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

write to 0xffffffff85caf310 of 4 bytes by task 0 on cpu 1:
 tick_nohz_stop_tick kernel/time/tick-sched.c:758 [inline]
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:949 [inline]
 tick_nohz_idle_stop_tick+0x525/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 start_secondary+0x207/0x260 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

read to 0xffffffff85caf310 of 4 bytes by task 0 on cpu 0:
 tick_nohz_stop_tick kernel/time/tick-sched.c:757 [inline]
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:949 [inline]
 tick_nohz_idle_stop_tick+0x193/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 rest_init+0xec/0xf6 init/main.c:452
 arch_call_rest_init+0x17/0x37
 start_kernel+0x83e/0x864 init/main.c:787
 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:472
 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:453
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xf5/0x159 lib/dump_stack.c:113
 panic+0x209/0x639 kernel/panic.c:219
 kcsan_report.cold+0xc/0x1b kernel/kcsan/report.c:303
 __kcsan_setup_watchpoint+0x3ee/0x510 kernel/kcsan/core.c:440
 __tsan_read4 kernel/kcsan/kcsan.c:30 [inline]
 __tsan_read4+0x2c/0x30 kernel/kcsan/kcsan.c:30
 tick_nohz_stop_tick kernel/time/tick-sched.c:757 [inline]
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:949 [inline]
 tick_nohz_idle_stop_tick+0x193/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 rest_init+0xec/0xf6 init/main.c:452
 arch_call_rest_init+0x17/0x37
 start_kernel+0x83e/0x864 init/main.c:787
 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:472
 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:453
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/15 12:01 https://github.com/google/ktsan.git kcsan 81f95ec7998e b5268b89 .config console log report ci2-upstream-kcsan-gce
2019/10/14 14:29 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/13 11:40 https://github.com/google/ktsan.git kcsan d724f94f63de 2f661ec4 .config console log report ci2-upstream-kcsan-gce
2019/10/12 22:10 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/12 04:24 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/11 13:30 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/11 07:42 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/11 03:40 https://github.com/google/ktsan.git kcsan d724f94f63de 1a3bad90 .config console log report ci2-upstream-kcsan-gce
2019/10/08 00:48 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
2019/10/06 22:11 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/06 14:53 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 21:39 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 20:41 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 06:03 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
2019/10/05 03:37 https://github.com/google/ktsan.git kcsan c1c7521f03c7 f3f7d9c8 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.