rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5499/1:b..l P5827/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=34289, q=294 ncpus=2)
task:syz-executor state:R running task stack:24104 pid:5827 tgid:5827 ppid:5822 task_flags:0x40050c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6966
preempt_schedule+0xae/0xc0 kernel/sched/core.c:6990
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1765 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x3842/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x410 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x22e0 kernel/exit.c:952
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
get_signal+0x125e/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7ea1b84e13
RSP: 002b:00007ffc9d3fa0c8 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00000000000016d6 RCX: 00007f7ea1b84e13
RDX: 0000000040000000 RSI: 00007ffc9d3fa0dc RDI: 00000000ffffffff
RBP: 00007ffc9d3fa0dc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
task:dhcpcd state:R running task stack:25080 pid:5499 tgid:5499 ppid:1 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
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:on_stack arch/x86/include/asm/stacktrace.h:60 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
RIP: 0010:deref_stack_regs arch/x86/kernel/unwind_orc.c:418 [inline]
RIP: 0010:unwind_next_frame+0xd2e/0x2390 arch/x86/kernel/unwind_orc.c:596
Code: 04 01 84 c0 0f 85 92 11 00 00 41 83 3e 00 0f 95 c0 4c 8b 64 24 10 4c 39 e3 0f 96 c1 20 c1 4c 39 e5 0f 97 c0 20 c8 3c 01 75 1c <49> 8d 84 24 a8 00 00 00 48 39 d8 0f 97 c1 48 39 e8 0f 96 c0 84 c1
RSP: 0018:ffffc9000216f738 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90002168000 RCX: 1ffff9200042df01
RDX: ffffc9000216f818 RSI: 0000000000000003 RDI: ffffffff8be1b9e0
RBP: ffffc90002170000 R08: 0000000000000022 R09: ffffffff8172aae5
R10: ffffc9000216f858 R11: ffffffff81acfd40 R12: ffffc9000216ff58
R13: 1ffff9200042df02 R14: ffffc9000216f808 R15: 1ffff9200042df03
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: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:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kfree+0x18e/0x440 mm/slub.c:4842
tomoyo_path_number_perm+0x47a/0x5a0 security/tomoyo/file.c:736
security_file_ioctl+0xcb/0x2d0 security/security.c:2913
__do_sys_ioctl fs/ioctl.c:901 [inline]
__se_sys_ioctl+0x47/0x170 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: 0033:0x7fb8be5c7378
RSP: 002b:00007ffc491afa48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000055e9ea61ee70 RCX: 00007fb8be5c7378
RDX: 00007ffc491afa50 RSI: 0000000000008921 RDI: 000000000000000f
RBP: 00007ffc491afa50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000055e9ea5ff0b0
R13: 000055e9ea61ee70 R14: 000055e9ea5ff0b0 R15: 00007ffc491afca0
rcu: rcu_preempt kthread starved for 8007 jiffies! g34289 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:26216 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:arch_stack_walk+0x110/0x150 arch/x86/kernel/stacktrace.c:27
Code: 78 ff ff ff 00 74 38 4c 8d bd 78 ff ff ff 4c 89 ff e8 a4 29 09 00 48 85 c0 74 24 48 89 df 48 89 c6 4d 89 f3 2e e8 50 b5 96 1e <84> c0 74 11 4c 89 ff e8 d4 2a 09 00 83 bd 78 ff ff ff 00 75 cf 65
RSP: 0018:ffffc90000a07268 EFLAGS: 00000296
RAX: 0000000000000001 RBX: ffffc90000a07320 RCX: bb39bc1bc3dfd400
RDX: dffffc0000000000 RSI: ffffffff89511263 RDI: ffffc90000a07320
RBP: ffffc90000a072f0 R08: ffffc90000a07330 R09: 0000000000000017
R10: ffffc90000a072b8 R11: ffffffff81acfd40 R12: ffff88801d2e5a00
R13: 0000000000000000 R14: ffffffff81acfd40 R15: ffffc90000a07268
FS: 0000000000000000(0000) GS:ffff888125d57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000ec030 CR3: 00000000782a4000 CR4: 00000000003526f0
Call Trace:
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:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4745
kfree_skb_reason include/linux/skbuff.h:1275 [inline]
enqueue_to_backlog+0xbc/0xfa0 net/core/dev.c:5193
netif_rx_internal+0x130/0x560 net/core/dev.c:5491
__netif_rx+0x78/0xc0 net/core/dev.c:5511
loopback_xmit+0x47a/0x6f0 drivers/net/loopback.c:90
__netdev_start_xmit include/linux/netdevice.h:5215 [inline]
netdev_start_xmit include/linux/netdevice.h:5224 [inline]
xmit_one net/core/dev.c:3830 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3846
sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344
qdisc_restart net/sched/sch_generic.c:409 [inline]
__qdisc_run+0xb16/0x15f0 net/sched/sch_generic.c:417
__dev_xmit_skb net/core/dev.c:4171 [inline]
__dev_queue_xmit+0xfe1/0x3a70 net/core/dev.c:4679
dev_queue_xmit include/linux/netdevice.h:3355 [inline]
neigh_hh_output include/net/neighbour.h:523 [inline]
neigh_output include/net/neighbour.h:537 [inline]
ip6_finish_output2+0x11bc/0x16a0 net/ipv6/ip6_output.c:141
synproxy_send_tcp_ipv6+0x4c1/0x680 net/netfilter/nf_synproxy_core.c:851
synproxy_send_client_synack_ipv6+0x80e/0xca0 net/netfilter/nf_synproxy_core.c:897
nft_synproxy_eval_v6+0x36e/0x560 net/netfilter/nft_synproxy.c:90
nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x409/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:272 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:491
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:317
__netif_receive_skb_one_core net/core/dev.c:5977 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6090
process_backlog+0x60e/0x14f0 net/core/dev.c:6442
__napi_poll+0xc4/0x480 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7605
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 de 02 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 d3 ad 21 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: bb39bc1bc3dfd400 RBX: ffffffff81976918 RCX: bb39bc1bc3dfd400
RDX: 0000000000000001 RSI: ffffffff8d982fba RDI: ffffffff8be1ba40
RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb
R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8fa0b3f0
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a5cb40
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:749
default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147