syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P30161/2:b..l P16/3:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=184029, q=366 ncpus=2)
task:ktimers/0       state:D stack:22872 pid:16    tgid:16    ppid:2      task_flags:0x4208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule_rtlock+0x30/0x70 kernel/sched/core.c:7390
 rtlock_slowlock_locked+0x35c5/0x3c20 kernel/locking/rtmutex.c:1895
 rtlock_slowlock kernel/locking/rtmutex.c:1922 [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
 spin_lock_bh include/linux/spinlock_rt.h:90 [inline]
 cfg80211_inform_single_bss_data+0xc22/0x1bf0 net/wireless/scan.c:2374
 cfg80211_inform_bss_data+0x258/0x3c40 net/wireless/scan.c:3238
 cfg80211_inform_bss_frame_data+0x3c7/0x730 net/wireless/scan.c:3329
 ieee80211_bss_info_update+0x791/0xa50 net/mac80211/scan.c:230
 ieee80211_scan_rx+0x552/0xa40 net/mac80211/scan.c:364
 __ieee80211_rx_handle_packet net/mac80211/rx.c:5395 [inline]
 ieee80211_rx_list+0x2b36/0x3950 net/mac80211/rx.c:5688
 ieee80211_rx_napi+0x1ad/0x3d0 net/mac80211/rx.c:5711
 ieee80211_rx include/net/mac80211.h:5437 [inline]
 ieee80211_handle_queued_frames+0xe4/0x1d0 net/mac80211/main.c:452
 tasklet_action_common+0x31c/0x600 kernel/softirq.c:938
 handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1151
 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
 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:kworker/u8:1    state:R  running task     stack:20456 pid:30161 tgid:30161 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7234
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413
 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
 _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198
 rt_mutex_slowtrylock kernel/locking/rtmutex.c:1408 [inline]
 __rt_spin_trylock kernel/locking/spinlock_rt.c:123 [inline]
 rt_spin_trylock+0xd2/0x2b0 kernel/locking/spinlock_rt.c:135
 alloc_from_pcs mm/slub.c:4795 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 kmem_cache_alloc_noprof+0x186/0x650 mm/slub.c:4959
 kmem_alloc_batch lib/debugobjects.c:371 [inline]
 fill_pool+0x165/0x610 lib/debugobjects.c:420
 debug_objects_fill_pool+0x63/0x80 lib/debugobjects.c:780
 debug_object_activate+0x6c/0x3b0 lib/debugobjects.c:869
 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
 kvfree_call_rcu+0x42/0x3c0 mm/slab_common.c:1961
 cfg80211_update_known_bss+0x8e5/0x1430 net/wireless/scan.c:1950
 __cfg80211_bss_update+0x147/0x2010 net/wireless/scan.c:1995
 cfg80211_inform_single_bss_data+0xc3b/0x1bf0 net/wireless/scan.c:2375
 cfg80211_inform_bss_data+0x258/0x3c40 net/wireless/scan.c:3238
 cfg80211_inform_bss_frame_data+0x3c7/0x730 net/wireless/scan.c:3329
 ieee80211_bss_info_update+0x791/0xa50 net/mac80211/scan.c:230
 ieee80211_rx_bss_info net/mac80211/ibss.c:1064 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1545 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1c8b/0x2be0 net/mac80211/ibss.c:1572
 ieee80211_iface_process_skb net/mac80211/iface.c:1763 [inline]
 ieee80211_iface_work+0x78a/0x1010 net/mac80211/iface.c:1817
 cfg80211_wiphy_work+0x29e/0x420 net/wireless/core.c:538
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g184029 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=137871
rcu: rcu_preempt kthread starved for 10502 jiffies! g184029 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:
task:rcu_preempt     state:I stack:23168 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
 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>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 3219 Comm: syz.3.9582 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:lock_is_held_type+0x106/0x150 kernel/locking/lockdep.c:5945
Code: 1a 00 00 b8 ff ff ff ff 65 0f c1 05 8c bd 49 07 83 f8 01 75 25 9c 58 a9 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 5b c6 03 00 cc 90 0f 0b 90 48 c7
RSP: 0018:ffffc90003d47830 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 0000000000000200 RSI: ffffffff8d8a508c RDI: ffffffff8ba94380
RBP: 00000000ffffffff R08: ffffffff891bb2d7 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888024aeeac8 R12: 0000000000000246
R13: ffff888027483e00 R14: ffffffff8dfc3080 R15: 0000000000000004
FS:  00007f65586a66c0(0000) GS:ffff888126211000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000216030 CR3: 000000002582c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lock_is_held include/linux/lockdep.h:249 [inline]
 __might_resched+0x37/0x480 kernel/sched/core.c:9159
 __rt_spin_lock kernel/locking/spinlock_rt.c:48 [inline]
 rt_spin_lock+0xc2/0x400 kernel/locking/spinlock_rt.c:57
 spin_lock_bh include/linux/spinlock_rt.h:90 [inline]
 __sock_map_delete net/core/sock_map.c:421 [inline]
 sock_map_delete_elem+0xb7/0x170 net/core/sock_map.c:452
 bpf_prog_ce4df7f5f440e1be+0x43/0x5e
 bpf_dispatcher_nop_func include/linux/bpf.h:1454 [inline]
 __bpf_prog_run include/linux/filter.h:723 [inline]
 bpf_prog_run include/linux/filter.h:730 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:747 [inline]
 bpf_flow_dissect+0x224/0x730 net/core/flow_dissector.c:1024
 bpf_prog_test_run_flow_dissector+0x3a4/0x610 net/bpf/test_run.c:1558
 bpf_prog_test_run+0x2cb/0x340 kernel/bpf/syscall.c:4859
 __sys_bpf+0xa22/0xd90 kernel/bpf/syscall.c:6436
 __do_sys_bpf kernel/bpf/syscall.c:6537 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6534 [inline]
 __x64_sys_bpf+0xba/0xd0 kernel/bpf/syscall.c:6534
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f655a44ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f65586a6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f655a6c5fa0 RCX: 00007f655a44ce59
RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007f655a4e2e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f655a6c6038 R14: 00007f655a6c5fa0 R15: 00007fff3805d668
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24671 Comm: kworker/1:0 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
RIP: 0010:__bfs_next kernel/locking/lockdep.c:1699 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1752 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1735/0x2ce0 kernel/locking/lockdep.c:5237
Code: 00 48 89 05 ad d8 d8 13 48 8d 84 24 90 00 00 00 48 89 05 9e 58 d8 13 31 ff 45 31 ff 4d 85 ff 4c 8b 6c 24 08 74 2e 49 8b 47 30 <48> 85 c0 74 25 48 8b 40 10 48 83 c0 30 49 8b 0f 48 89 8c 24 d8 00
RSP: 0018:ffffc90006e6e228 EFLAGS: 00000082
RAX: ffffffff96053a38 RBX: 00000000000003cd RCX: 00000000001c541d
RDX: ffffffff962fd9e8 RSI: ffff88806a4dea48 RDI: 00000000000003cd
RBP: f997bd6e7c6703be R08: ffffc90006e6e1f0 R09: 0000000000000020
R10: 0000000000000000 R11: ffffffff81a124a0 R12: 0000000000000836
R13: ffff88806a4dea48 R14: ffff88806a4ddd00 R15: ffffffff9636d198
FS:  0000000000000000(0000) GS:ffff888126211000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000022b030 CR3: 00000000110a4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73
 ktime_expiry_to_cycles+0x4e/0x1e0 kernel/time/timekeeping.c:910
 clockevent_set_next_coupled kernel/time/clockevents.c:314 [inline]
 clockevents_program_event+0x199/0x630 kernel/time/clockevents.c:360
 hrtimer_rearm kernel/time/hrtimer.c:2141 [inline]
 __hrtimer_rearm_deferred+0x26f/0x430 kernel/time/hrtimer.c:2161
 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline]
 hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline]
 irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:505 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:542 [inline]
 irqentry_exit+0x8b7/0x8f0 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198
Code: f7 e8 2d 71 76 f6 f7 c3 00 02 00 00 74 05 e8 90 65 a2 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 74 90 68 f6 65 8b 05 ad ed 45 07 85 c0 74 18 5b 41 5e e9 51 3c
RSP: 0018:ffffc90006e6e680 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000287 RCX: 0000000080000001
RDX: 0000000000000002 RSI: ffffffff8d6401ff RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffffffff8f8afef7 R09: 1ffffffff1f15fde
R10: dffffc0000000000 R11: fffffbfff1f15fdf R12: ffff8880b89261c0
R13: 0000000000000000 R14: ffff8880b89261c0 R15: 0000000000000287
 __mod_timer+0xb8f/0xf10 kernel/time/timer.c:1139
 sk_reset_timer+0x23/0xc0 net/core/sock.c:3722
 tcp_ack_snd_check net/ipv4/tcp_input.c:6168 [inline]
 tcp_rcv_established+0xfa4/0x2910 net/ipv4/tcp_input.c:6662
 tcp_v4_do_rcv+0x959/0x13f0 net/ipv4/tcp_ipv4.c:1851
 tcp_v4_rcv+0x27d2/0x3160 net/ipv4/tcp_ipv4.c:2245
 ip_protocol_deliver_rcu+0x21d/0x440 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241
 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
 dst_input include/net/dst.h:481 [inline]
 ip_sublist_rcv_finish+0x1f0/0x240 net/ipv4/ip_input.c:623
 ip_list_rcv_finish net/ipv4/ip_input.c:675 [inline]
 ip_sublist_rcv+0x767/0xa70 net/ipv4/ip_input.c:683
 ip_list_rcv+0x3ec/0x440 net/ipv4/ip_input.c:717
 __netif_receive_skb_list_ptype net/core/dev.c:6250 [inline]
 __netif_receive_skb_list_core+0x804/0x830 net/core/dev.c:6296
 __netif_receive_skb_list net/core/dev.c:6348 [inline]
 netif_receive_skb_list_internal+0x995/0xcf0 net/core/dev.c:6439
 gro_normal_list include/net/gro.h:523 [inline]
 gro_flush_normal include/net/gro.h:531 [inline]
 napi_complete_done+0x299/0x730 net/core/dev.c:6807
 virtqueue_napi_complete drivers/net/virtio_net.c:740 [inline]
 virtnet_poll+0x26eb/0x3100 drivers/net/virtio_net.c:3024
 __napi_poll+0xae/0x550 net/core/dev.c:7729
 napi_poll net/core/dev.c:7792 [inline]
 net_rx_action+0x621/0xd70 net/core/dev.c:7949
 handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:199 [inline]
 wg_packet_handshake_receive_worker+0x8b9/0x10a0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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>