INFO: rcu detected stall in batadv_nc

INFO: rcu detected stall in batadv_nc_worker (3)
Status: upstream: reported on 2020/10/01 10:35
Reported-by: syzbot+69904c3b4a09e8fa2e1b@syzkaller.appspotmail.com
First crash: 163d, last: 11d

similar bugs (2):
Kernel	Title	Repro	Bisected	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in batadv_nc_worker			7	321d	322d	0/17	closed as invalid on 2019/12/04 14:04
upstream	INFO: rcu detected stall in batadv_nc_worker (2)			4	286d	286d	0/17	closed as invalid on 2020/01/09 08:13

Sample crash report:

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=c26/1/0x4000000000000000 softirq=43565/43565 fqs=35 
	(detected by 1, t=10502 jiffies, g=82829, q=190)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 18432 Comm: kworker/u4:8 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:arch_atomic_set arch/x86/include/asm/atomic.h:41 [inline]
RIP: 0010:atomic_set include/asm-generic/atomic-instrumented.h:46 [inline]
RIP: 0010:taprio_set_budget net/sched/sch_taprio.c:517 [inline]
RIP: 0010:advance_sched+0x40a/0x990 net/sched/sch_taprio.c:744
Code: 2b 05 00 00 41 8b 44 24 2c 4d 8d 74 24 20 31 d2 be 04 00 00 00 4c 89 f7 48 69 c0 e8 03 00 00 48 f7 f5 48 89 c5 e8 96 b3 19 fb <4c> 89 f2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 4c
RSP: 0018:ffffc90000007d80 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff88809de44b40 RCX: ffffffff869d36fa
RDX: ffffed101342eeb5 RSI: 0000000000000004 RDI: ffff88809a1775a0
RBP: 0000000140000002 R08: 0000000000000001 R09: ffff88809a1775a3
R10: ffffed101342eeb4 R11: 0000000000000000 R12: ffff88809a177580
R13: 16c61b7dad8c36fb R14: ffff88809a1775a0 R15: 16c61b7dad8c36fb
FS:  0000000000000000(0000) GS:ffff8880ae400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32422000 CR3: 0000000099ea1000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1524 [inline]
 __hrtimer_run_queues+0x6a9/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x147/0x5f0 arch/x86/kernel/apic/apic.c:1097
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0xb2/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline]
RIP: 0010:lock_acquire+0x30a/0xaf0 kernel/locking/lockdep.c:5003
Code: 00 4c 89 f8 48 c1 f8 06 48 8d 3c c5 48 99 59 8b e8 5b de 5a 00 4c 0f a3 3d 1b 8d fd 09 0f 83 c9 fd ff ff 65 ff 05 46 f2 a5 7e <4c> 8b 3d e7 dd f8 09 4d 85 ff 0f 84 89 00 00 00 48 ba 00 00 00 00
RSP: 0018:ffffc900084f7b08 EFLAGS: 00000283
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815c0c25
RDX: fffffbfff16b332a RSI: 0000000000000008 RDI: ffffffff8b599948
RBP: ffff88804a904058 R08: 0000000000000000 R09: ffffffff8b59994f
R10: fffffbfff16b3329 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175
 spin_lock_bh include/linux/spinlock.h:359 [inline]
 batadv_nc_purge_paths+0xdf/0x3a0 net/batman-adv/network-coding.c:441
 batadv_nc_worker+0x868/0xe50 net/batman-adv/network-coding.c:721
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
rcu: rcu_preempt kthread starved for 10429 jiffies! g82829 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:29096 pid:   10 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0xec9/0x2280 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879
 rcu_gp_fqs_loop kernel/rcu/tree.c:1890 [inline]
 rcu_gp_kthread+0xb2c/0x1ca0 kernel/rcu/tree.c:2060
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (11):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Maintainers
ci-upstream-kasan-gce-root	2020/10/09 00:16	upstream	3d006ee4	92390980	.config	log	report	info	davem@davemloft.net, jhs@mojatatu.com, jiri@resnulli.us, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, xiyou.wangcong@gmail.com
ci-upstream-kasan-gce-smack-root	2020/08/06 00:31	upstream	fffe3ae0	0487ea6f	.config	log	report		linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-root	2020/07/08 03:46	upstream	7cc2a8ea	51095195	.config	log	report		davem@davemloft.net, jhs@mojatatu.com, jiri@resnulli.us, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, xiyou.wangcong@gmail.com
ci-upstream-kasan-gce-smack-root	2020/07/07 14:37	upstream	7cc2a8ea	51095195	.config	log	report		linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-selinux-root	2020/05/30 22:53	upstream	ffeb595d	6f3e1c7c	.config	log	report		bp@alien8.de, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, tony.luck@intel.com, x86@kernel.org
ci-upstream-kasan-gce-root	2020/05/10 07:00	upstream	1d3962ae	8742a2b9	.config	log	report		bp@alien8.de, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, tony.luck@intel.com, x86@kernel.org
ci-upstream-kasan-gce-386	2020/07/13 03:50	upstream	4437dd6e	9ebcc5b1	.config	log	report		fweisbec@gmail.com, linux-kernel@vger.kernel.org, mingo@kernel.org, tglx@linutronix.de
ci-upstream-net-this-kasan-gce	2020/07/22 15:39	net	2c4dc314	128cd85f	.config	log	report		fweisbec@gmail.com, linux-kernel@vger.kernel.org, mingo@kernel.org, tglx@linutronix.de
ci-upstream-net-this-kasan-gce	2020/07/03 01:55	net	e4b9a72d	bed10395	.config	log	report		davem@davemloft.net, jhs@mojatatu.com, jiri@resnulli.us, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, xiyou.wangcong@gmail.com
ci-upstream-net-kasan-gce	2020/09/01 04:44	net-next	c30a3c95	d5a3ae1f	.config	log	report		linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-linux-next-kasan-gce-root	2020/09/02 03:53	linux-next	b36c9697	abf9ba4f	.config	log	report		linux-kernel@vger.kernel.org, tglx@linutronix.de