rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=985c/1/0x4000000000000000 softirq=48622/48625 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7435/1:b..l
rcu: (detected by 0, t=10505 jiffies, g=31113, q=388 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9023 Comm: syz-executor Not tainted 6.16.0-rc3-next-20250625-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x8/0x90 kernel/kcov.c:294
Code: 48 89 44 11 20 e9 58 b3 b1 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 f0 9f 92 65 8b 15 38 31 e0 10 81 e2 00 01 ff 00
RSP: 0018:ffffc90000a08d00 EFLAGS: 00000046
RAX: ffffffff8b6aa8b8 RBX: ffff8880b8727d10 RCX: ffff888074d89e00
RDX: 0000000000010000 RSI: ffff8880290c2340 RDI: 0000000000000001
RBP: 1ffff11005218468 R08: ffffffff8fa18d37 R09: 1ffffffff1f431a6
R10: dffffc0000000000 R11: fffffbfff1f431a7 R12: ffff8880290c2340
R13: dffffc0000000000 R14: ffff8880290c2340 R15: 0000000000000001
FS: 0000555558b62500(0000) GS:ffff888125d21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f66c460df98 CR3: 0000000052950000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
timerqueue_del+0x48/0x100 lib/timerqueue.c:55
__remove_hrtimer kernel/time/hrtimer.c:1121 [inline]
__run_hrtimer kernel/time/hrtimer.c:1741 [inline]
__hrtimer_run_queues+0x364/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:873 [inline]
RIP: 0010:__page_table_check_zero+0x40d/0x530 mm/page_table_check.c:145
Code: d8 98 8b be 66 03 00 00 48 c7 c2 20 d9 98 8b e8 19 e1 6e ff 48 c7 c7 60 bf 13 8e 4c 89 f6 e8 fa c6 6e ff 48 83 c4 20 5b 41 5c <41> 5d 41 5e 41 5f 5d e9 77 61 78 ff e8 e2 d7 90 ff 49 ff cf e9 47
RSP: 0018:ffffc90003c8f5b0 EFLAGS: 00000286
RAX: f083cd40a1a7da00 RBX: 0000000000000000 RCX: f083cd40a1a7da00
RDX: 0000000000000000 RSI: ffffffff8db80324 RDI: ffffffff8be31c80
RBP: 0000000000000001 R08: ffff88801e40e41f R09: 1ffff11003c81c83
R10: dffffc0000000000 R11: ffffed1003c81c84 R12: fffa8000782da000
R13: 0000000000000001 R14: ffffffff822ee13a R15: 00000000000782da
page_table_check_alloc include/linux/page_table_check.h:35 [inline]
post_alloc_hook+0x253/0x2a0 mm/page_alloc.c:1849
prep_new_page mm/page_alloc.c:1856 [inline]
get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145
__alloc_pages_noprof mm/page_alloc.c:5179 [inline]
alloc_pages_bulk_noprof+0x560/0x710 mm/page_alloc.c:5099
___alloc_pages_bulk mm/kasan/shadow.c:344 [inline]
__kasan_populate_vmalloc mm/kasan/shadow.c:368 [inline]
kasan_populate_vmalloc+0xba/0x1a0 mm/kasan/shadow.c:417
alloc_vmap_area+0xd51/0x1490 mm/vmalloc.c:2092
__get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3187
__vmalloc_node_range_noprof+0x301/0x12f0 mm/vmalloc.c:3853
vmalloc_user_noprof+0xad/0xf0 mm/vmalloc.c:4046
kcov_ioctl+0x55/0x640 kernel/kcov.c:716
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f443d18e52b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffd7855c780 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f443d18e52b
RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d9
RBP: 00007f443d3b6118 R08: 00000000000000d8 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
task:kworker/u8:16 state:R running task stack:21160 pid:7435 tgid:7435 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7019
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:-1 [inline]
RIP: 0010:unwind_next_frame+0xc49/0x2390 arch/x86/kernel/unwind_orc.c:585
Code: 39 f8 0f 97 c1 4c 39 e0 0f 96 c0 20 c8 3c 01 0f 85 df 0c 00 00 48 89 df e8 84 23 00 00 48 89 c3 48 bd 00 00 00 00 00 fc ff df <48> 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 18 74 08 4c 89 ff e8 9f 3a
RSP: 0018:ffffc90003bbf538 EFLAGS: 00000202
RAX: ffffffff81696c34 RBX: ffffffff81696c34 RCX: 1ffff92000777e01
RDX: ffffffff9030e3aa RSI: 0000000000000002 RDI: ffffc90003bbf660
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff81728c65
R10: ffffc90003bbf668 R11: fffff52000777ed9 R12: ffffc90003bc0000
R13: 1ffff92000777ecf R14: ffffc90003bbf668 R15: ffffc90003bb8000
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4782
batadv_forw_packet_free+0x65/0x1f0 net/batman-adv/send.c:473
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10505 jiffies! g31113 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
__schedule_loop kernel/sched/core.c:6774 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6789
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2060
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2262
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 12 Comm: kworker/u8:0 Not tainted 6.16.0-rc3-next-20250625-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 60 69 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 65 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 64 0b
RSP: 0018:ffffc900001176a0 EFLAGS: 00000293
RAX: ffffffff81b45790 RBX: ffff8880b863b180 RCX: ffff88801ce9da00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000117800 R08: ffffffff8fa18d37 R09: 1ffffffff1f431a6
R10: dffffc0000000000 R11: fffffbfff1f431a7 R12: 1ffff110170e7f59
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b873fac8
FS: 0000000000000000(0000) GS:ffff888125c21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff00cd6010 CR3: 000000000df36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline]
smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2901
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:850
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245