syzbot


KCSAN: data-race in add_timer / run_timer_softirq

Status: closed as invalid on 2019/11/19 14:04
Subsystems: kernel
[Documentation on labels]
First crash: 1651d, last: 1621d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in add_timer / run_timer_softirq (2) fs 81 1409d 1480d 0/26 auto-closed as invalid on 2020/07/18 23:41

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

write to 0xffff88812bf1b6c8 of 8 bytes by interrupt on cpu 1:
 expire_timers kernel/time/timer.c:1445 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x496/0xcd0 kernel/time/timer.c:1786
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1af/0x280 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355
 start_secondary+0x168/0x1b0 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

read to 0xffff88812bf1b6c8 of 8 bytes by task 23 on cpu 0:
 __mod_timer kernel/time/timer.c:1026 [inline]
 mod_timer kernel/time/timer.c:1100 [inline]
 add_timer+0x16f/0x550 kernel/time/timer.c:1136
 __queue_delayed_work+0x13b/0x1d0 kernel/workqueue.c:1649
 queue_delayed_work_on+0xf3/0x110 kernel/workqueue.c:1674
 queue_delayed_work include/linux/workqueue.h:509 [inline]
 bond_netdev_notify_work drivers/net/bonding/bond_main.c:1355 [inline]
 bond_netdev_notify_work+0x150/0x160 drivers/net/bonding/bond_main.c:1342
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 23 Comm: kworker/u4:2 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bond0 bond_netdev_notify_work
==================================================================

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/15 06:35 https://github.com/google/ktsan.git kcsan 5863cc791e4c 79248ee8 .config console log report ci2-upstream-kcsan-gce
2019/11/12 08:55 https://github.com/google/ktsan.git kcsan 7f2955e0d056 048f2d49 .config console log report ci2-upstream-kcsan-gce
2019/11/06 14:50 https://github.com/google/ktsan.git kcsan 94c006602e13 da505f84 .config console log report ci2-upstream-kcsan-gce
2019/11/04 12:08 https://github.com/google/ktsan.git kcsan 05f2236801fe 18e12644 .config console log report ci2-upstream-kcsan-gce
2019/11/04 12:06 https://github.com/google/ktsan.git kcsan 05f2236801fe 18e12644 .config console log report ci2-upstream-kcsan-gce
2019/11/03 21:40 https://github.com/google/ktsan.git kcsan 05f2236801fe b35fad31 .config console log report ci2-upstream-kcsan-gce
2019/11/02 21:10 https://github.com/google/ktsan.git kcsan 05f2236801fe d603afc9 .config console log report ci2-upstream-kcsan-gce
2019/10/30 20:53 https://github.com/google/ktsan.git kcsan 05f2236801fe a41ca8fa .config console log report ci2-upstream-kcsan-gce
2019/10/23 14:21 https://github.com/google/ktsan.git kcsan 05f2236801fe b602d64b .config console log report ci2-upstream-kcsan-gce
2019/10/17 14:51 https://github.com/google/ktsan.git kcsan 05f2236801fe 8c88c9c1 .config console log report ci2-upstream-kcsan-gce
2019/10/15 23:43 https://github.com/google/ktsan.git kcsan e3d315561216 d4ea592f .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.