rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4996/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=229645, q=500 ncpus=2)
task:udevd state:R running task stack:22360 pid:4996 tgid:4996 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7463
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
rcu_read_unlock include/linux/rcupdate.h:867 [inline]
class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
is_module_text_address+0x147/0x1e0 kernel/module/main.c:3923
kernel_text_address+0x94/0xe0 kernel/extable.c:119
__kernel_text_address+0xd/0x30 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385
arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
__slab_free+0x274/0x2c0 mm/slub.c:5613
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4570 [inline]
slab_alloc_node mm/slub.c:4899 [inline]
kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4906
alloc_filename fs/namei.c:142 [inline]
do_getname+0x2e/0x250 fs/namei.c:182
getname include/linux/fs.h:2526 [inline]
getname_maybe_null include/linux/fs.h:2533 [inline]
class_filename_maybe_null_constructor include/linux/fs.h:2557 [inline]
vfs_fstatat+0x45/0x170 fs/stat.c:368
__do_sys_newfstatat fs/stat.c:538 [inline]
__se_sys_newfstatat fs/stat.c:532 [inline]
__x64_sys_newfstatat+0x151/0x200 fs/stat.c:532
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb57f11b0a
RSP: 002b:00007ffdc8f275e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00005565c9ac0428 RCX: 00007feb57f11b0a
RDX: 00007ffdc8f275f0 RSI: 00005565c9aaeed3 RDI: 00000000ffffff9c
RBP: 00005565e6e89148 R08: 00063478c1c69200 R09: 3fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffdc8f275f0 R14: 0000000000000000 R15: 00063478c1c69200
rcu: rcu_preempt kthread starved for 10486 jiffies! g229645 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x389/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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:
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 04/18/2026
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline]
RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457
Code: 8b e8 6c b3 21 0a 65 66 8b 05 0c c2 b1 11 66 85 c0 75 32 bf 01 00 00 00 e8 c5 fb 0b 00 e8 50 15 46 00 fb 65 8b 05 e8 c1 b1 11 <85> c0 75 05 e8 df bc ab ff 5b 41 5e e9 47 8a 24 0a cc 90 0f 0b 90
RSP: 0018:ffffc90000a085c8 EFLAGS: 00000206
RAX: 0000000080000101 RBX: 0000000000000200 RCX: 0000000080000101
RDX: 0000000000000000 RSI: ffffffff8dfad387 RDI: ffffffff8c28b7e0
RBP: ffffc90000a087d0 R08: ffffffff9030daf7 R09: 1ffffffff2061b5e
R10: dffffc0000000000 R11: fffffbfff2061b5f R12: ffff8880650eb1c0
R13: dffffc0000000000 R14: ffffffff8a6d31ff R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125387000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000800c1018 CR3: 000000007da5c000 CR4: 00000000003526f0
Call Trace:
local_bh_enable include/linux/bottom_half.h:33 [inline]
ip6t_do_table+0x137d/0x1560 net/ipv6/netfilter/ip6_tables.c:375
ip6table_mangle_hook+0x2b3/0x740 net/ipv6/netfilter/ip6table_mangle.c:73
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316
ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:545
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6202 [inline]
__netif_receive_skb net/core/dev.c:6315 [inline]
process_backlog+0x7dd/0x1950 net/core/dev.c:6666
__napi_poll+0xae/0x340 net/core/dev.c:7733
napi_poll net/core/dev.c:7796 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7953
handle_softirqs+0x22a/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
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: 6b 7d 02 e9 93 f7 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 f3 01 20 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000242
RAX: 0000000002faab9b RBX: ffffffff819a858a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8dfad387 RDI: ffffffff8c28b7e0
RBP: ffffc90000197f10 R08: ffff8880b87339db R09: 1ffff110170e673b
R10: dffffc0000000000 R11: ffffed10170e673c R12: 0000000000000001
R13: 1ffff11003b5b000 R14: 0000000000000001 R15: 1ffff11003b5b000
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147