rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16980/1:b..l P7141/1:b..l
rcu: (detected by 0, t=10506 jiffies, g=96581, q=184 ncpus=2)
task:kworker/u8:25 state:R running task stack:22248 pid:7141 tgid:7141 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_mcast_mla_update
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x350 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 54 ec d7 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90004987318 EFLAGS: 00000206
RAX: 2cde801989acb600 RBX: 0000000000000000 RCX: 2cde801989acb600
RDX: 0000000000000000 RSI: ffffffff8d977664 RDI: ffffffff8bbf7760
RBP: ffffffff81745035 R08: 0000000000000000 R09: ffffffff81745035
R10: ffffc900049874d8 R11: ffffffff81adcc30 R12: 0000000000000002
R13: ffffffff8df3d700 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6663 [inline]
kfree+0x1c0/0x680 mm/slub.c:6871
batadv_mcast_mla_list_free net/batman-adv/multicast.c:667 [inline]
__batadv_mcast_mla_update net/batman-adv/multicast.c:924 [inline]
batadv_mcast_mla_update+0x3362/0x3600 net/batman-adv/multicast.c:946
process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
task:udevd state:R running task stack:24264 pid:16980 tgid:16980 ppid:5197 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 56 f0 27 f6 90 0f 0b 90 90 90 eb c4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 31 c0 83 3d 67 ec 21 04 00 74 1e 83 3d 7a 1b 22 04 00
RSP: 0018:ffffc9000c1df998 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff81ac432d RCX: fcac1a4f2947f400
RDX: 0000000000000001 RSI: ffffffff8bbf7740 RDI: 00007f5f534a7407
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81ac432d
R10: ffffc9000c1dfa78 R11: ffffffff81adcc30 R12: ffff88807af00000
R13: 0000000000000000 R14: 00007f5f534a7407 R15: 1ffff9200183bf4e
rcu_read_unlock include/linux/rcupdate.h:895 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
is_module_text_address+0x13e/0x1e0 kernel/module/main.c:3858
kernel_text_address+0x94/0xe0 kernel/extable.c:119
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
slab_free_hook mm/slub.c:2501 [inline]
slab_free mm/slub.c:6663 [inline]
kmem_cache_free+0x48f/0x640 mm/slub.c:6774
fput_close_sync+0x113/0x220 fs/file_table.c:573
__do_sys_close fs/open.c:1584 [inline]
__se_sys_close fs/open.c:1569 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1569
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f534a7407
RSP: 002b:00007ffc35c59880 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f5f53b79880 RCX: 00007f5f534a7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffc35c59920 R14: 0000000000000000 R15: 0000000000000009
rcu: rcu_preempt kthread starved for 10475 jiffies! g96581 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:25728 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 34 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xccf/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 6a 9c 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 15 98 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 f9 97
RSP: 0018:ffffc90000aa7660 EFLAGS: 00000293
RAX: ffffffff81b64557 RBX: 1ffff110170e8129 RCX: ffff88801ea99e80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000aa77e0 R08: ffffffff8f7df377 R09: 1ffffffff1efbe6e
R10: dffffc0000000000 R11: fffffbfff1efbe6f R12: ffff8880b8740948
R13: dffffc0000000000 R14: ffff8880b863bb00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125eb8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fca60283f70 CR3: 000000000dd38000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline]
smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2921
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:854
process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246