rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4360/1:b..l P9351/1:b..l
(detected by 1, t=10503 jiffies, g=43057, q=261 ncpus=2)
task:syz.7.1188 state:R running task stack:25280 pid:9351 ppid:9087 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:ipv4_conntrack_defrag+0x1/0x5b0 net/ipv4/netfilter/nf_defrag_ipv4.c:64
Code: e8 f4 4f 0c f9 eb a3 89 d9 80 e1 07 80 c1 03 38 c1 7c c8 48 89 df e8 4e 50 0c f9 eb be 66 2e 0f 1f 84 00 00 00 00 00 66 90 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 10 49 89 d6 48 89 f3 49 bd 00
RSP: 0018:ffffc900041e7360 EFLAGS: 00000246
RAX: 1ffff11005050982 RBX: ffff888028284c10 RCX: ffffc9001f800000
RDX: ffffc900041e7420 RSI: ffff888054494b40 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 000000000000f77b R09: 0000000000400000
R10: 00000000001eef68 R11: 1ffffffff215c448 R12: 0000000000000000
R13: ffff888028284c08 R14: ffffffff88c49ca0 R15: ffffc900041e7420
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:614
nf_hook+0x211/0x370 include/linux/netfilter.h:257
__ip_local_out+0x49c/0x5d0 net/ipv4/ip_output.c:115
ip_local_out net/ipv4/ip_output.c:124 [inline]
ip_send_skb+0x48/0x1c0 net/ipv4/ip_output.c:1600
udp_send_skb+0xa88/0x1580 net/ipv4/udp.c:993
udp_sendmsg+0x1b0c/0x2390 net/ipv4/udp.c:1281
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x59b/0x970 net/socket.c:2519
___sys_sendmsg+0x21c/0x290 net/socket.c:2573
__sys_sendmmsg+0x272/0x490 net/socket.c:2659
__do_sys_sendmmsg net/socket.c:2688 [inline]
__se_sys_sendmmsg net/socket.c:2685 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3387f8ebe9
RSP: 002b:00007f3388d42038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f33881c5fa0 RCX: 00007f3387f8ebe9
RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000003
RBP: 00007f3388011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000f000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f33881c6038 R14: 00007f33881c5fa0 R15: 00007ffc5a88e5a8
task:kworker/u4:6 state:R running task stack:22440 pid:4360 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__should_failslab+0x97/0xf0 mm/failslab.c:44
Code: 48 c1 e8 03 42 0f b6 04 20 84 c0 75 50 41 f6 47 03 02 74 d2 c1 eb 0d 83 e3 01 49 83 c6 1c 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 <84> c0 75 18 41 8b 36 48 c7 c7 20 cd c1 8c 89 da 5b 41 5c 41 5e 41
RSP: 0018:ffffc900048b7838 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: ffffc900048b78c0 RSI: 0000000000000a20 RDI: ffff888017441c80
RBP: 0000000000000a20 R08: 0000000000000a20 R09: ffffed100a85025d
R10: ffffed100a85025d R11: 1ffff1100a85025c R12: dffffc0000000000
R13: 00000000ffffffff R14: ffff888017441c9c R15: 0000000000000001
should_failslab+0x5/0x20 mm/slab_common.c:1440
slab_pre_alloc_hook+0x59/0x310 mm/slab.h:712
slab_alloc_node mm/slub.c:3318 [inline]
__kmem_cache_alloc_node+0x4f/0x260 mm/slub.c:3437
kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
kmalloc include/linux/slab.h:563 [inline]
batadv_forw_packet_alloc+0x1e5/0x380 net/batman-adv/send.c:519
batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:562 [inline]
batadv_iv_ogm_queue_add+0x77b/0xcf0 net/batman-adv/bat_iv_ogm.c:670
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:849 [inline]
batadv_iv_ogm_schedule+0xaaf/0xe90 net/batman-adv/bat_iv_ogm.c:868
batadv_iv_send_outstanding_bat_ogm_packet+0x72d/0x840 net/batman-adv/bat_iv_ogm.c:1712
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: rcu_preempt kthread starved for 10573 jiffies! g43057 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:27464 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9348 Comm: syz.0.1190 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:task_curr+0x0/0xb0 kernel/sched/core.c:2152
Code: e9 80 e1 07 80 c1 03 38 c1 0f 8c b1 fe ff ff 4c 89 ef e8 83 06 79 00 e9 a4 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <41> 57 41 56 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df 4c 8d
RSP: 0018:ffffc90000007da0 EFLAGS: 00000046
RAX: 000000000c000000 RBX: 1ffff1100327836e RCX: ffff888073f63b80
RDX: 0000000000010000 RSI: 0000000000000000 RDI: ffff88802fb58000
RBP: fffffffffffff998 R08: dffffc0000000000 R09: ffff88808930c484
R10: ffffed1011261895 R11: 1ffff11011261890 R12: 0000000000000000
R13: ffff88802fb58000 R14: 0000000000010000 R15: ffff8880193c1b70
FS: 00007f708903b6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ff17a9d58 CR3: 0000000025187000 CR4: 00000000003506f0
DR0: 0000000000000001 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
wants_signal kernel/signal.c:1000 [inline]
complete_signal+0x310/0xc50 kernel/signal.c:1027
__send_signal_locked+0xb0a/0xde0 kernel/signal.c:1195
do_send_sig_info kernel/signal.c:1301 [inline]
group_send_sig_info+0x1f6/0x250 kernel/signal.c:1449
do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:840
irq_work_single+0xd1/0x230 kernel/irq_work.c:211
irq_work_run_list kernel/irq_work.c:242 [inline]
irq_work_run+0x152/0x2e0 kernel/irq_work.c:251
__sysvec_irq_work+0xba/0x350 arch/x86/kernel/irq_work.c:22
instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 7f c1 f7 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90003357cb0 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: ffffffff8c5e3b88 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff5200066af85
R10: fffff5200066af85 R11: 1ffff9200066af84 R12: ffff8880b8e33e01
R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020
arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
irq_work_queue+0x95/0x140 kernel/irq_work.c:114
bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879
____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline]
bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886
bpf_prog_7ba5217f62dcd359+0x38/0x3c
bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324
__bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18
syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f708812adb9
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f708903ab40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f70883c6098 RCX: 00007f708812adb9
RDX: 00007f708903ab40 RSI: 00007f708903ac70 RDI: 0000000000000011
RBP: 00007f70883c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f70883c6128 R14: 00007ffceb915500 R15: 00007ffceb9155e8