rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12363/1:b..l P4977/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=118657, q=1892 ncpus=1)
task:udevd state:R running task stack:22856 pid:4977 tgid:4977 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 bb 8b 7e 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 46 92 3c 0f 0f 82 ac 02 00 00 8b 35 0e c6 3c 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 5d 8b 7e 12 0f 85 ec 02 00 00 48 83 c4
RSP: 0018:ffffc900056b7500 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e1823aa RDI: ffffffff8c402680
RBP: ffffffff8ebe8200 R08: 00000000b4340513 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x162/0x1e0 mm/page_owner.c:165
__reset_page_owner+0x84/0x190 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4584 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x2bf/0x820 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [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:1895
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+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd15e311b0a
RSP: 002b:00007ffc80b500e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000055ba90575420 RCX: 00007fd15e311b0a
RDX: 00007ffc80b500f0 RSI: 000055ba90563ef3 RDI: 00000000ffffff9c
RBP: 000055babafaa668 R08: 00063478c1c69200 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc80b500f0 R14: 0000000000000000 R15: 00063478c1c69200
task:syz-executor state:R running task stack:28280 pid:12363 tgid:12363 ppid:10698 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_notrace+0x5f/0xd0 kernel/sched/core.c:7506
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:753
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x301/0x370 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x162/0x1e0 mm/page_owner.c:165
__reset_page_owner+0x84/0x190 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 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:5334 [inline]
__kmalloc_noprof+0x322/0x820 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
tomoyo_path_perm+0x3a7/0x460 security/tomoyo/file.c:836
tomoyo_path_symlink+0x97/0xe0 security/tomoyo/tomoyo.c:212
security_path_symlink+0x152/0x2d0 security/security.c:1502
filename_symlinkat+0x122/0x560 fs/namei.c:5683
__do_sys_symlinkat fs/namei.c:5705 [inline]
__se_sys_symlinkat fs/namei.c:5700 [inline]
__x64_sys_symlinkat+0x9c/0xe0 fs/namei.c:5700
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f31f5b9d0d7
RSP: 002b:00007ffdee6ce838 EFLAGS: 00000202 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f31f5b9d0d7
RDX: 00007f31f5c35fc5 RSI: 00000000ffffff9c RDI: 00007ffdee6ce8d0
RBP: 00007ffdee6ce87c R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000004b
R13: 00000000000927c0 R14: 0000000000069c84 R15: 00007ffdee6ce8d0
rcu: rcu_preempt kthread starved for 5003 jiffies! g118657 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:27592 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 0 UID: 0 PID: 3224 Comm: kworker/R-bat_e Tainted: G S L syzkaller #0 PREEMPT(full)
Tainted: [S]=CPU_OUT_OF_SPEC, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 a3 cb 7e 12 83 f8 01 0f 85 27 01 00 00 9c 58 f6 c4 02 0f 85 12 01 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 <48> 8b 44 24 10 65 48 2b 05 ad 84 7e 12 0f 85 4d 01 00 00 48 83 c4
RSP: 0018:ffffc90000007288 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8ebe8200 RCX: ffffc90000007294
RDX: 0000000000000005 RSI: ffffffff8e1823aa RDI: ffffffff8c402680
RBP: ffffffff8a63289c R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888033c48000
R13: ffff88807af92740 R14: 0000000000000202 R15: 0000000000000006
FS: 0000000000000000(0000) GS:ffff888123dd8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f068ce4ed81 CR3: 0000000032a4c000 CR4: 00000000003526f0
DR0: 0000000000000008 DR1: 0000000000000007 DR2: 0000000000000004
DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
ip6_output+0x2e1/0xa60 net/ipv6/ip6_output.c:250
dst_output include/net/dst.h:470 [inline]
ip6_local_out+0xcb/0x1f0 net/ipv6/output_core.c:128
synproxy_send_tcp_ipv6+0x5f3/0x700 net/netfilter/nf_synproxy_core.c:861
synproxy_send_client_synack_ipv6+0x601/0x7a0 net/netfilter/nf_synproxy_core.c:907
nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline]
nft_synproxy_do_eval+0x911/0xce0 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e5/0x19d0 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0xf3/0x400 net/netfilter/nft_chain_filter.c:162
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619
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:545
dst_input include/net/dst.h:480 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:119 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ipv6_rcv+0x263/0x3d0 net/ipv6/ip6_input.c:351
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6212
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6325
process_backlog+0x37a/0x1580 net/core/dev.c:6676
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7735
napi_poll net/core/dev.c:7798 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7955
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
do_softirq kernel/softirq.c:523 [inline]
do_softirq+0xac/0xe0 kernel/softirq.c:510
__local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x21c/0x3d0 net/batman-adv/translation-table.c:1366
batadv_tt_purge+0x8b/0xbd0 net/batman-adv/translation-table.c:3565
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
rescuer_thread+0x905/0x14a0 kernel/workqueue.c:3629
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245