rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=d2d4/1/0x4000000000000000 softirq=50597/50597 fqs=1
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12/1:b..l
rcu: (detected by 1, t=10505 jiffies, g=53045, q=566 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11950 Comm: syz.7.1147 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:rb_link_node include/linux/rbtree.h:98 [inline]
RIP: 0010:__rb_add include/linux/rbtree.h:238 [inline]
RIP: 0010:rb_add_linked include/linux/rbtree.h:281 [inline]
RIP: 0010:timerqueue_linked_add+0x242/0x2e0 lib/timerqueue.c:96
Code: e8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ef e8 85 e3 8c f6 4d 89 75 00 49 8d 7d 08 ba 10 00 00 00 31 f6 e8 51 e5 8c f6 4c 89 f8 <48> c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 5c e3 8c f6 4d 89 2f 4c
RSP: 0018:ffffc90000007d58 EFLAGS: 00000002
RAX: ffff8880b8628418 RBX: ffff8880b8628418 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff888068ce4318
RBP: dffffc0000000000 R08: ffff888068ce4317 R09: ffff888068ce4308
R10: dffffc0000000000 R11: ffffed100d19c863 R12: 1ffff110170c5078
R13: ffff888068ce4300 R14: 0000000000000000 R15: ffff8880b8628418
FS: 00007f8d8bcb36c0(0000) GS:ffff888125290000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c32da1d CR3: 00000000a68d1000 CR4: 0000000000350ef0
Call Trace:
enqueue_hrtimer+0x18e/0x2c0 kernel/time/hrtimer.c:1117
__run_hrtimer kernel/time/hrtimer.c:1946 [inline]
__hrtimer_run_queues+0x4d2/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 1a f0 f6 f5 48 89 df e8 22 65 f7 f5 e8 2d fb 22 f6 fb bf 01 00 00 00 b2 e7 e8 f5 65 8b 05 7b 10 8e 07 85 c0 74 07 5b e9 4c 51 65 f5
RSP: 0018:ffffc90003b1f370 EFLAGS: 00000202
RAX: 0000000000001db3 RBX: ffff8880294ffc00 RCX: 0000000080000001
RDX: 0000000000000007 RSI: ffffffff8dfa5b55 RDI: 0000000000000001
RBP: ffffc90003b1f4d0 R08: ffffffff9030a8f7 R09: 1ffffffff206151e
R10: dffffc0000000000 R11: fffffbfff206151f R12: ffffc90003b1f420
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000001
spin_unlock_irq include/linux/spinlock.h:402 [inline]
shmem_add_to_page_cache+0xa5e/0xd40 mm/shmem.c:928
shmem_alloc_and_add_folio+0x866/0xf80 mm/shmem.c:2001
shmem_get_folio_gfp+0x5a9/0x1670 mm/shmem.c:2564
shmem_fault+0x179/0x390 mm/shmem.c:2765
__do_fault+0x138/0x2a0 mm/memory.c:5458
do_read_fault mm/memory.c:5893 [inline]
do_fault mm/memory.c:6027 [inline]
do_pte_missing+0x2093/0x33f0 mm/memory.c:4550
handle_pte_fault mm/memory.c:6411 [inline]
__handle_mm_fault mm/memory.c:6549 [inline]
handle_mm_fault+0x1bd7/0x3170 mm/memory.c:6718
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x1683/0x2720 mm/gup.c:1428
populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860
__mm_populate+0x25f/0x390 mm/gup.c:1963
mm_populate include/linux/mm.h:4137 [inline]
vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d8ad9cdd9
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:00007f8d8bcb3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f8d8b015fa0 RCX: 00007f8d8ad9cdd9
RDX: b635773f056bbeea RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f8d8ae32d69 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8d8b016038 R14: 00007f8d8b015fa0 R15: 00007ffde46f0828
task:kworker/u8:0 state:R running task stack:20992 pid:12 tgid:12 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:5388 [inline]
__schedule+0x17b4/0x5680 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/0x730 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:121 [inline]
RIP: 0010:lock_release+0x69/0x3c0 kernel/locking/lockdep.c:5881
Code: 05 fc c8 8e 0e 73 0d e8 45 f7 08 00 84 c0 0f 84 94 02 00 00 83 3d b6 fb 8e 0e 00 0f 84 1c 02 00 00 65 8b 05 99 65 97 11 85 c0 <0f> 85 0d 02 00 00 65 4c 8b 3d e1 1f 97 11 41 83 bf 8c 0b 00 00 00
RSP: 0018:ffffc90000117878 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000000011e RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c28acc0 RDI: ffffffff8c28ac80
RBP: ffffc90000117a30 R08: ffffffff8b6f715a R09: ffffffff8e95cd60
R10: dffffc0000000000 R11: ffffed1006802517 R12: ffff88803c1fa1c0
R13: ffffffff8b6f715a R14: ffffffff8e95cd60 R15: ffff8880843108f0
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:781 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:836 [inline]
batadv_iv_ogm_schedule+0x71f/0xf50 net/batman-adv/bat_iv_ogm.c:876
batadv_iv_send_outstanding_bat_ogm_packet+0x6c8/0x7e0 net/batman-adv/bat_iv_ogm.c:1712
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 starved for 10230 jiffies! g53045 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x17b4/0x5680 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: 1 UID: 0 PID: 8685 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 da 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 85 03 0c 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 6a 03 0c 00 eb e5 44 89
RSP: 0018:ffffc900035e7700 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b873c148 RCX: ffff88802e749ec0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900035e7840 R08: ffffffff9030a8f7 R09: 1ffffffff206151e
R10: dffffc0000000000 R11: fffffbfff206151f R12: 1ffff110170c8589
R13: dffffc0000000000 R14: ffff8880b8642c48 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125390000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3411bff8 CR3: 000000000e74a000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:906
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