rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5179/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=83841, q=1191 ncpus=2)
task:udevd state:R running task stack:23608 pid:5179 tgid:5179 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7234
irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_is_held_type+0xf5/0x140 kernel/locking/lockdep.c:5945
Code: ff ff ff ff 65 0f c1 15 91 38 7e 08 83 fa 01 8b 44 24 04 75 2d 9c 5a 80 e6 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 83 c4 08 <5b> 5d 41 5c 41 5d 41 5e 41 5f e9 7c 2c 03 00 c3 cc cc cc cc 31 c0
RSP: 0018:ffffc90003417788 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffffffff8e7e93e0 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8de4be56 RDI: ffffffff8c1aefa0
RBP: ffff88807ab4c900 R08: 0000000000000006 R09: 0000000000001000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffff
R13: 0000000000000246 R14: ffff88807ab4d468 R15: 0000000000000002
lookup_page_ext+0x6e/0x100 mm/page_ext.c:258
page_ext_iter_begin include/linux/page_ext.h:133 [inline]
__update_page_owner_free_handle.isra.0+0xa4/0x4d0 mm/page_owner.c:284
__reset_page_owner+0x93/0x190 mm/page_owner.c:321
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:406
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5219 [inline]
__kmalloc_noprof+0x301/0x850 mm/slub.c:5231
kmalloc_noprof include/linux/slab.h:966 [inline]
tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
security_inode_getattr+0x116/0x280 security/security.c:1869
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x11f/0x3f0 fs/stat.c:356
vfs_fstatat+0x77/0xe0 fs/stat.c:373
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd796b11b0a
RSP: 002b:00007ffe1b7e7228 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000055daefcf6408 RCX: 00007fd796b11b0a
RDX: 00007ffe1b7e7230 RSI: 000055daefce4ef3 RDI: 00000000ffffff9c
RBP: 000055db04c21668 R08: 00063489548db180 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe1b7e7230 R14: 0000000000000000 R15: 00063489548db180
rcu: rcu_preempt kthread starved for 7755 jiffies! g83841 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:28680 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:hlock_id kernel/locking/lockdep.c:433 [inline]
RIP: 0010:__lock_acquire+0x524/0x2630 kernel/locking/lockdep.c:5225
Code: 44 c7 f9 32 43 21 a8 60 0f 85 70 08 00 00 48 89 d0 89 d6 48 c1 e8 20 89 c7 41 89 c0 01 c2 c1 c7 04 0f b6 43 22 44 0f b7 4b 20 <83> e0 03 66 41 81 e1 ff 1f c1 e0 0d 44 09 c8 98 44 29 c0 31 f8 89
RSP: 0018:ffffc90000a082c0 EFLAGS: 00000883
RAX: 000000000000000c RBX: ffff88801e6b3010 RCX: 0000000000000003
RDX: 000000009be35b6b RSI: 000000006290c103 RDI: 000000009529a683
RBP: ffff88801e6b2480 R08: 0000000039529a68 R09: 0000000000002000
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff88812444a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f45e93ffd90 CR3: 0000000076152000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:1088 [inline]
debug_check_no_obj_freed+0x1c9/0x630 lib/debugobjects.c:1129
slab_free_hook mm/slub.c:2618 [inline]
slab_free mm/slub.c:6124 [inline]
kmem_cache_free+0x3c8/0x6a0 mm/slub.c:6254
kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1151
__kfree_skb net/core/skbuff.c:1218 [inline]
consume_skb net/core/skbuff.c:1450 [inline]
consume_skb+0xd1/0x110 net/core/skbuff.c:1444
nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:92 [inline]
nft_synproxy_do_eval+0x949/0xd50 net/netfilter/nft_synproxy.c:146
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e8/0x1930 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0xee/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip6_input+0xe0/0x2f0 net/ipv6/ip6_input.c:500
dst_input include/net/dst.h:480 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ipv6_rcv+0x261/0x610 net/ipv6/ip6_input.c:311
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6156
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6269
process_backlog+0x37a/0x1580 net/core/dev.c:6620
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7684
napi_poll net/core/dev.c:7747 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7899
handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: d8 82 02 c3 cc cc cc cc 0f 1f 00 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 43 0c 1c 00 fb f4 bc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df0 EFLAGS: 00000242
RAX: 000000000601d2fb RBX: ffff88801e6b2480 RCX: ffffffff8b8f7c75
RDX: 0000000000000000 RSI: ffffffff8de71ed4 RDI: ffffffff8c1aefa0
RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed10170a6795
R10: ffff8880b8533cab R11: 0000000000000000 R12: ffffed1003cd6490
R13: 0000000000000001 R14: ffffffff90d96410 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x35b/0x4b0 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148