INFO: rcu detected stall in batadv_nc

INFO: rcu detected stall in batadv_nc_worker (3)
Status: moderation: reported on 2020/05/11 18:21
Reported-by: syzbot+a16816d5de06e9999d53@syzkaller.appspotmail.com
First crash: 94d, last: 6d12h

similar bugs (2):
Kernel	Title	Repro	Bisected	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in batadv_nc_worker			7	252d	253d	0/17	closed as invalid on 2019/12/04 14:04
upstream	INFO: rcu detected stall in batadv_nc_worker (2)			4	217d	217d	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-...!: (1 GPs behind) idle=22e/1/0x4000000000000000 softirq=85361/85365 fqs=8 
	(detected by 1, t=10502 jiffies, g=114061, q=1511)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 194 Comm: kworker/u4:4 Not tainted 5.8.0-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_local_save_flags arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:787 [inline]
RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
RIP: 0010:_raw_spin_lock_irqsave+0x3c/0xc0 kernel/locking/spinlock.c:159
Code: 03 49 bf 00 00 00 00 00 fc ff df 42 80 3c 38 00 74 0c 48 c7 c7 b0 d5 4b 89 e8 a0 97 92 f9 48 83 3d 38 61 2a 01 00 74 79 9c 58 <0f> 1f 44 00 00 49 89 c6 48 c7 c0 c0 d5 4b 89 48 c1 e8 03 42 80 3c
RSP: 0018:ffffc90000007d40 EFLAGS: 00000082
RAX: 0000000000000082 RBX: ffffffff8ba182b8 RCX: 000000000000d6e0
RDX: 0000000080010001 RSI: ffffffff894eec80 RDI: ffffffff8ba182b8
RBP: ffffffff894eec80 R08: ffffffff816542f4 R09: fffff52000000fb0
R10: fffff52000000fb0 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff11015d04ed2 R14: dffffc0000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004ddaf0 CR3: 0000000090ca1000 CR4: 00000000001506f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 debug_object_activate+0x62/0x5f0 lib/debugobjects.c:636
 debug_hrtimer_activate kernel/time/hrtimer.c:416 [inline]
 debug_activate kernel/time/hrtimer.c:476 [inline]
 enqueue_hrtimer kernel/time/hrtimer.c:965 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1537 [inline]
 __hrtimer_run_queues+0x510/0x930 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_apic_timer_interrupt+0x94/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline]
RIP: 0010:lock_release+0x3c4/0x750 kernel/locking/lockdep.c:5026
Code: 48 c1 e8 03 42 80 3c 28 00 74 0c 48 c7 c7 b8 d5 4b 89 e8 3f 0b 5a 00 48 83 3d df d4 f1 07 00 0f 84 5c 03 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 50 0f 85 40
RSP: 0018:ffffc90001037bf8 EFLAGS: 00000282
RAX: 1ffffffff1297ab7 RBX: 1ffff110151d2949 RCX: ffff8880a8e94180
RDX: ffff8880a8e94a48 RSI: ffffffff894ea290 RDI: 0000000000000282
RBP: 9644b5a36c253f0c R08: dffffc0000000000 R09: fffffbfff131b08e
R10: fffffbfff131b08e R11: 0000000000000000 R12: 0000000000000282
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8880a8e94a4c
 rcu_read_unlock include/linux/rcupdate.h:688 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline]
 batadv_nc_worker+0x261/0x5c0 net/batman-adv/network-coding.c:718
 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
rcu: rcu_preempt kthread starved for 10486 jiffies! g114061 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I28608    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x979/0xce0 kernel/sched/core.c:4527

Crashes (8):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Maintainers
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