rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1490/1:b..l P29/2:b..l
rcu: (detected by 1, t=10502 jiffies, g=13633, q=386 ncpus=2)
task:ktimers/1 state:R running task stack:22440 pid:29 tgid:29 ppid:2 task_flags:0x4208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369
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_irqrestore include/linux/spinlock_rt.h:129 [inline]
class_spinlock_irqsave_destructor include/linux/spinlock.h:619 [inline]
snd_seq_timer_interrupt+0x31d/0x430 sound/core/seq/seq_timer.c:131
snd_timer_process_callbacks sound/core/timer.c:796 [inline]
snd_timer_interrupt+0x108d/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
task:kworker/u8:14 state:R running task stack:20888 pid:1490 tgid:1490 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7512
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x14f/0x730 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x7f/0x3c0 kernel/locking/lockdep.c:5881
Code: 26 77 e8 0d 00 0f 84 1c 02 00 00 65 8b 05 f9 17 ca 10 85 c0 0f 85 0d 02 00 00 65 4c 8b 3d 01 d1 c9 10 41 83 bf f4 0b 00 00 00 <0f> 85 f7 01 00 00 49 81 3e 40 f3 2d 93 0f 84 ea 01 00 00 9c 5b fa
RSP: 0018:ffffc90006b0f630 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88801a00ab00 RCX: 0000000080000001
RDX: ffffea000190d810 RSI: ffffffff8ba74c40 RDI: ffffffff8ba74c00
RBP: ffffc90006b0f788 R08: ffffffff8b1e5760 R09: ffffffff8dfc8140
R10: dffffc0000000000 R11: fffffbfff1f11a5f R12: ffff88805f435800
R13: ffffffff8220c154 R14: ffff88801a00ab58 R15: ffff888029b38000
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
spin_unlock_irqrestore include/linux/spinlock_rt.h:129 [inline]
__refill_objects_node+0x4f4/0x560 mm/slub.c:7154
refill_objects+0x62/0x3d0 mm/slub.c:7238
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__do_kmalloc_node mm/slub.c:5294 [inline]
__kmalloc_node_track_caller_noprof+0x60b/0x7e0 mm/slub.c:5403
kmalloc_reserve net/core/skbuff.c:635 [inline]
pskb_expand_head+0x230/0x1390 net/core/skbuff.c:2302
__skb_cow include/linux/skbuff.h:3879 [inline]
skb_cow_head include/linux/skbuff.h:3913 [inline]
batadv_skb_head_push+0x169/0x200 net/batman-adv/mesh-interface.c:71
batadv_send_skb_packet+0xc8/0x690 net/batman-adv/send.c:81
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0x631/0x7e0 net/batman-adv/bat_iv_ogm.c:1700
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
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 10497 jiffies! g13633 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=5224
rcu: rcu_preempt kthread starved for 10498 jiffies! g13633 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:27432 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
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: ab 6e 02 e9 43 c8 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 63 6b 2d 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: 00000246
RAX: 00000000001e5165 RBX: ffffffff819953aa RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d60269b RDI: ffffffff8ba74c60
RBP: ffffffff8dc07eb0 R08: ffff8880b8833e9b R09: 1ffff110171067d3
R10: dffffc0000000000 R11: ffffed10171067d4 R12: 0000000000000000
R13: 1ffffffff1b9fdd8 R14: 0000000000000000 R15: 1ffffffff1b9fdd8
FS: 0000000000000000(0000) GS:ffff88812617c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9a9cf8fff8 CR3: 000000003189e000 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