rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29/2:b..l P32/1:b..l P13/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=12981, q=711 ncpus=2)
task:kworker/u8:1 state:R running task stack:20824 pid:13 tgid:13 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
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:547 [inline]
irqentry_exit+0x14f/0x760 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 61 9e 7c 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b 79 ca 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 38 d9 eb
RSP: 0018:ffffc900001278e0 EFLAGS: 00000282
RAX: 8c2b3b917f29df00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000008aeb1d2b RSI: ffffffff8d86383f RDI: ffffffff8ba74fe0
RBP: ffffffff8b1f38e0 R08: ffffffff8b1f38e0 R09: ffffffff8dfc8180
R10: dffffc0000000000 R11: fffffbfff1f11e7f R12: 0000000000000002
R13: ffffffff8dfc8180 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:838 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
rt_spin_lock+0x1fc/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
skb_dequeue+0x2d/0x150 net/core/skbuff.c:3943
ieee80211_iface_work+0x1092/0x1390 net/mac80211/iface.c:1856
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:kworker/1:0H state:R running task stack:25704 pid:32 tgid:32 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events_highpri snd_vmidi_output_work
Call Trace:
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:547 [inline]
irqentry_exit+0x14f/0x760 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 61 9e 7c 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b 79 ca 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 38 d9 eb
RSP: 0018:ffffc90000a6f820 EFLAGS: 00000282
RAX: c977fa2a9bfd4f00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000edd16c00 RSI: ffffffff8d86383f RDI: ffffffff8ba74fe0
RBP: ffffffff819da45f R08: ffffffff819da45f R09: ffff88802b71a8b0
R10: dffffc0000000000 R11: fffffbfff1f11e7f R12: 0000000000000000
R13: ffff88802b71a8b0 R14: 0000000000000001 R15: 0000000000000246
rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56
spin_lock include/linux/spinlock_rt.h:45 [inline]
__wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
__snd_rawmidi_transmit_ack+0x27b/0x360 sound/core/rawmidi.c:1448
snd_rawmidi_transmit+0x77/0xe0 sound/core/rawmidi.c:1492
snd_vmidi_output_work+0x1a5/0x3f0 sound/core/seq/seq_virmidi.c:151
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:ktimers/1 state:R running task stack:23728 pid:29 tgid:29 ppid:2 task_flags:0x4208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x16ec/0x5620 kernel/sched/core.c:7189
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
rt_mutex_wake_up_q kernel/locking/rtmutex.c:581 [inline]
rt_mutex_slowunlock+0x681/0x8b0 kernel/locking/rtmutex.c:1478
spin_unlock include/linux/spinlock_rt.h:109 [inline]
snd_timer_process_callbacks sound/core/timer.c:794 [inline]
snd_timer_interrupt+0x1046/0x1330 sound/core/timer.c:912
snd_hrtimer_callback+0x21e/0x390 sound/core/hrtimer.c:51
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x405/0xb10 kernel/time/hrtimer.c:1994
hrtimer_run_softirq+0x18f/0x260 kernel/time/hrtimer.c:2011
handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0x69/0x100 kernel/softirq.c:1151
smpboot_thread_fn+0x541/0xa50 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
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g12981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=7043
rcu: rcu_preempt kthread starved for 10500 jiffies! g12981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:27768 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
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+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: fb 6d 02 e9 c3 c9 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 8c 2c 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8dc07dc0 EFLAGS: 00000242
RAX: 0000000000108f7f RBX: ffffffff8199580a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d605220 RDI: ffffffff8ba74fe0
RBP: ffffffff8dc07eb0 R08: ffff8880b8833e9b R09: 1ffff110171067d3
R10: dffffc0000000000 R11: ffffed10171067d4 R12: 0000000000000000
R13: 1ffffffff1b9fdd8 R14: 0000000000000000 R15: 1ffffffff1b9fdd8
FS: 0000000000000000(0000) GS:ffff888126174000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f44c85b7f98 CR3: 0000000058d1e000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
rest_init+0x2de/0x300 init/main.c:762
start_kernel+0x38a/0x3e0 init/main.c:1220
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147