rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P821/1:b..l P16/3:b..l P5778/2:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=23149, q=1181 ncpus=2)
task:kworker/u8:9    state:R  running task     stack:21480 pid:5778  tgid:5778  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:_ieee802_11_parse_elems_full+0x2ddb/0x42f0 net/mac80211/parse.c:343
Code: b6 1b 48 8b 84 24 98 00 00 00 42 80 3c 30 00 74 08 4c 89 e7 e8 26 c7 8f f7 4d 8b 2c 24 48 8b 84 24 90 00 00 00 42 80 3c 30 00 <4c> 8b 7c 24 60 74 08 4c 89 ff e8 06 c7 8f f7 4c 8b 64 24 20 49 01
RSP: 0018:ffffc9000410e760 EFLAGS: 00000246
RAX: 1ffff92000821dca RBX: 0000000000000008 RCX: ffffffff8a9bcf93
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410eb00
RBP: ffffc9000410eb90 R08: ffffc9000410eb07 R09: 1ffff92000821d60
R10: dffffc0000000000 R11: fffff52000821d61 R12: ffffc9000410ee48
R13: ffff88803bdad31d R14: dffffc0000000000 R15: 0000000000000001
 ieee802_11_parse_elems_full+0x121a/0x29f0 net/mac80211/parse.c:1120
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2518 [inline]
 ieee80211_inform_bss+0x161/0x1160 net/mac80211/scan.c:79
 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline]
 cfg80211_inform_single_bss_data+0xd2f/0x1b80 net/wireless/scan.c:2372
 cfg80211_inform_bss_data+0x266/0x3c40 net/wireless/scan.c:3229
 cfg80211_inform_bss_frame_data+0x3c7/0x730 net/wireless/scan.c:3320
 ieee80211_bss_info_update+0x794/0xa40 net/mac80211/scan.c:230
 ieee80211_rx_bss_info net/mac80211/ibss.c:1088 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1569 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1901/0x2cb0 net/mac80211/ibss.c:1596
 ieee80211_iface_process_skb net/mac80211/iface.c:1795 [inline]
 ieee80211_iface_work+0x845/0x1390 net/mac80211/iface.c:1849
 cfg80211_wiphy_work+0x2cf/0x460 net/wireless/core.c:513
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:ktimers/0       state:D stack:24408 pid:16    tgid:16    ppid:2      task_flags:0x4208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule_rtlock+0x30/0x70 kernel/sched/core.c:7347
 rtlock_slowlock_locked+0x3638/0x3c80 kernel/locking/rtmutex.c:1887
 rtlock_slowlock kernel/locking/rtmutex.c:1914 [inline]
 rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
 __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
 rt_spin_lock+0x165/0x400 kernel/locking/spinlock_rt.c:57