rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5198/1:b..l P5187/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=14997, q=727 ncpus=2)
task:klogd           state:R  running task     stack:23720 pid:5187  tgid:5187  ppid:1      task_flags:0x400100 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 fb 9c f3 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900030d7118 EFLAGS: 00000206
RAX: 9c892cfe9cdc7b00 RBX: 0000000000000000 RCX: 9c892cfe9cdc7b00
RDX: 0000000000000000 RSI: ffffffff8d9d0e89 RDI: ffffffff8bc073e0
RBP: ffffffff8173cd25 R08: 0000000000000000 R09: ffffffff8173cd25
R10: ffffc900030d72d8 R11: ffffffff81ac6cd0 R12: 0000000000000002
R13: ffffffff8e13d2e0 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3317 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3864
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
 __slab_free+0x2b9/0x390 mm/slub.c:5913
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:408
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5634 [inline]
 __kmalloc_node_track_caller_noprof+0x568/0x800 mm/slub.c:5743
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6671
 sock_alloc_send_pskb+0x84d/0x980 net/core/sock.c:2965
 unix_dgram_sendmsg+0x461/0x1850 net/unix/af_unix.c:2153
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0e95d46407
RSP: 002b:00007fffcfe166f0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f0e95bf6c80 RCX: 00007f0e95d46407
RDX: 0000000000000047 RSI: 00007fffcfe16830 RDI: 0000000000000003
RBP: 00007fffcfe16c60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007fffcfe16c78
R13: 00007fffcfe16830 R14: 000000000000002c R15: 00007fffcfe16830
 </TASK>
task:udevd           state:R  running task     stack:23336 pid:5198  tgid:5198  ppid:1      task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <c3> cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 6b ba e3 f5 cc
RSP: 0018:ffffc90003097700 EFLAGS: 00000282
RAX: ffff88801ce29980 RBX: dffffc0000000000 RCX: ffff88807696dac0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: ffffffff822f4e8e
R10: 000000000000000e R11: ffffffff81ac6cd0 R12: 0000000000056eb8
R13: 0000000000000000 R14: ffffffff822f4e8e R15: 000000201383e4fb
 page_ext_iter_begin include/linux/page_ext.h:132 [inline]
 __update_page_owner_free_handle+0x103/0x470 mm/page_owner.c:272
 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3317 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3864
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
 __slab_free+0x2b9/0x390 mm/slub.c:5913
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:408
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5634 [inline]
 __kmalloc_noprof+0x411/0x7f0 mm/slub.c:5646
 kmalloc_noprof include/linux/slab.h:961 [inline]
 tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822
 security_inode_getattr+0x12f/0x330 security/security.c:2416
 vfs_getattr fs/stat.c:259 [inline]
 vfs_fstat fs/stat.c:281 [inline]
 __do_sys_newfstat fs/stat.c:555 [inline]
 __se_sys_newfstat fs/stat.c:550 [inline]
 __x64_sys_newfstat+0xfc/0x200 fs/stat.c:550
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd4ee111ad7
RSP: 002b:00007fff623e4868 EFLAGS: 00000297 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 000055af120948a0 RCX: 00007fd4ee111ad7
RDX: 00007fd4ee1efea0 RSI: 00007fff623e4870 RDI: 000000000000000c
RBP: 00007fd4ee1efff0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000297 R12: 000000000000000a
R13: 0000000000003fff R14: 0000000000000000 R15: 000055af120948a0
 </TASK>
rcu: rcu_preempt kthread starved for 9752 jiffies! g14997 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:27288 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:unwind_next_frame+0x199/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 04 28 84 c0 0f 85 3c 1b 00 00 4c 89 6c 24 50 4c 89 64 24 20 4c 89 7c 24 48 48 89 5c 24 10 0f b6 1b 48 8b 44 24 30 80 3c 28 00 <4c> 8b 7c 24 18 74 08 4c 89 ff e8 e8 25 b2 00 4d 8b 27 48 83 f3 01
RSP: 0018:ffffc90000006b58 EFLAGS: 00000246
RAX: 1ffff92000000d8e RBX: 0000000000000000 RCX: a2a36d502cfeac00
RDX: 0000000000000000 RSI: ffffffff8bc073c0 RDI: ffffffff8bc07380
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8173cd25
R10: ffffc90000006c78 R11: ffffffff81ac6cd0 R12: 1ffff92000000d85
R13: ffffc90000006c78 R14: ffffc90000006c28 R15: ffffffff8173cd25
FS:  0000000000000000(0000) GS:ffff888125d0d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1b78d03810 CR3: 0000000074f08000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 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:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:342 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5324
 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 synproxy_send_client_synack_ipv6+0x169/0xca0 net/netfilter/nf_synproxy_core.c:873
 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+0x40c/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:158 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500
 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
 __netif_receive_skb_one_core net/core/dev.c:6079 [inline]
 __netif_receive_skb+0xd3/0x380 net/core/dev.c:6192
 process_backlog+0x60e/0x14f0 net/core/dev.c:6544
 __napi_poll+0xc7/0x360 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
 handle_softirqs+0x286/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 33 b1 1b 00 f3 0f 1e fa fb f4 <e9> c8 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c6
RAX: a2a36d502cfeac00 RBX: ffffffff8196bc07 RCX: a2a36d502cfeac00
RDX: 0000000000000001 RSI: ffffffff8d7e7f1e RDI: ffffffff8bc073e0
RBP: ffffffff8de07ea8 R08: ffff8880b8632fdb R09: 1ffff110170c65fb
R10: dffffc0000000000 R11: ffffed10170c65fc R12: ffffffff8f9dfa70
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a40
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e7/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 rest_init+0x2de/0x300 init/main.c:757
 start_kernel+0x3ae/0x410 init/main.c:1111
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>