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WARNING: CPU: 2 PID: 2927 at kernel/rcu/tree_stall.h:824 rcu_check_gp_start_stall.part.0+0x325/0x4b0 kernel/rcu/tree_stall.h:816
Modules linked in:
CPU: 2 PID: 2927 Comm: kworker/u16:1 Not tainted 5.12.0-rc1-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_check_gp_start_stall.part.0+0x325/0x4b0 kernel/rcu/tree_stall.h:824
Code: 0f 88 fa 00 00 00 be 04 00 00 00 48 c7 c7 e0 54 e4 8f e8 2e 71 57 00 b8 01 00 00 00 87 05 53 98 84 0e 85 c0 0f 85 c9 00 00 00 <0f> 0b 48 81 fd 00 c3 f7 8b 48 c7 c3 4c 66 c6 8d 74 58 48 b8 00 00
RSP: 0018:ffffc90000540e50 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000100001a4a RCX: ffffffff815fbc82
RDX: fffffbfff1fc8a9c RSI: 0000000000000004 RDI: ffffffff8fe454e0
RBP: ffffffff8bf7c300 R08: 0000000000000001 R09: 0000000000000003
R10: fffffbfff1fc8a9c R11: ffffffff8bf7c340 R12: 1ffffffff1781e30
R13: 0000000000000246 R14: ffff88802cc35fd2 R15: ffff88802cc36058
FS:  0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005577856ab6b8 CR3: 0000000012eeb000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_check_gp_start_stall kernel/rcu/tree_stall.h:787 [inline]
 rcu_core+0x4d6/0x1280 kernel/rcu/tree.c:2789
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu kernel/softirq.c:422 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:434
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:__local_bh_enable_ip+0xa8/0x120 kernel/softirq.c:205
Code: 1d 6d 39 bd 7e 65 8b 05 66 39 bd 7e a9 00 ff ff 00 74 45 bf 01 00 00 00 e8 f5 04 09 00 e8 c0 6a 34 00 fb 65 8b 05 48 39 bd 7e <85> c0 74 58 5b 5d c3 65 8b 05 76 40 bd 7e 85 c0 75 a2 0f 0b eb 9e
RSP: 0018:ffffc9000b7f7c08 EFLAGS: 00000206
RAX: 0000000080000000 RBX: 00000000fffffe00 RCX: 1ffffffff1f6186a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff88a31c65 R08: 0000000000000001 R09: ffffffff8fab6947
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888022251728
R13: ffff888022250c00 R14: dffffc0000000000 R15: ffffffff88a31ea0
 spin_unlock_bh include/linux/spinlock.h:399 [inline]
 batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:467
 batadv_nc_worker+0x868/0xe50 net/batman-adv/network-coding.c:718
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294