rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5627/1:b..l P2/1:b..l P6557/3:b..l P5925/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=24397, q=999767 ncpus=2)
task:udevd           state:R  running task     stack:25624 pid:5925  tgid:5925  ppid:4998   task_flags:0x40014c flags:0x00080800
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1821/0x5740 kernel/sched/core.c:7189
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0xdb9/0x2550 arch/x86/include/asm/stacktrace.h:-1
Code: 89 dd 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 74 08 48 89 df e8 71 1e ba 00 48 89 5c 24 60 4c 89 64 24 18 <49> 8d 5c 24 f8 4d 8b 66 10 48 b8 00 00 00 00 00 fc ff df 48 8b 4c
RSP: 0018:ffffc9000d5cf138 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffc9000d5cf218 RCX: ffffffff90516134
RDX: ffffffff90d16e1e RSI: 0000000000000002 RDI: ffffffff8c28b700
RBP: 1ffff92001ab9e42 R08: 0000000000000001 R09: ffffffff8e95cce0
R10: ffffc9000d5cf258 R11: ffffffff81b0e210 R12: ffffc9000d5cf850
R13: 1ffff92001ab9e43 R14: ffffc9000d5cf208 R15: ffffc9000d5c8000
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 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
 kmem_alloc_batch lib/debugobjects.c:371 [inline]
 fill_pool+0x156/0x580 lib/debugobjects.c:420
 debug_objects_fill_pool lib/debugobjects.c:752 [inline]
 debug_object_activate+0x4a3/0x580 lib/debugobjects.c:841
 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
 __call_rcu_common kernel/rcu/tree.c:3116 [inline]
 call_rcu+0x43/0x890 kernel/rcu/tree.c:3251
 slab_free_hook mm/slub.c:2653 [inline]
 slab_free mm/slub.c:6251 [inline]
 kmem_cache_free+0x462/0x650 mm/slub.c:6378
 anon_vma_free mm/rmap.c:137 [inline]
 __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2917
 put_anon_vma mm/internal.h:216 [inline]
 unlink_anon_vmas+0x58b/0x730 mm/rmap.c:536
 free_pgtables+0x836/0xb70 mm/memory.c:414
 exit_mmap+0x490/0x9e0 mm/mmap.c:1312
 __mmput+0x118/0x430 kernel/fork.c:1178
 exit_mm+0x1f6/0x2d0 kernel/exit.c:582
 do_exit+0x6a2/0x22c0 kernel/exit.c:964
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 __do_sys_exit_group kernel/exit.c:1130 [inline]
 __se_sys_exit_group kernel/exit.c:1128 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1128
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4badaf16c5
RSP: 002b:00007ffeee7dbce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000055f8806a21f0 RCX: 00007f4badaf16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 000055f880678910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeee7dbd30 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:syz.3.255       state:R  running task     stack:25288 pid:6557  tgid:6549  ppid:5649   task_flags:0x400040 flags:0x08080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1821/0x5740 kernel/sched/core.c:7189
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 ipt_do_table+0x13d2/0x1630 net/ipv4/netfilter/ip_tables.c:357
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
 nf_hook+0x22a/0x3a0 include/linux/netfilter.h:273
 NF_HOOK_COND include/linux/netfilter.h:306 [inline]
 ip_output+0x269/0x450 net/ipv4/ip_output.c:438
 __ip_queue_xmit+0x116a/0x1bb0 net/ipv4/ip_output.c:534
 __tcp_transmit_skb+0x2d76/0x4790 net/ipv4/tcp_output.c:1715
 tcp_transmit_skb net/ipv4/tcp_output.c:1733 [inline]
 tcp_write_xmit+0x1be0/0x6540 net/ipv4/tcp_output.c:3061
 __tcp_push_pending_frames+0x97/0x380 net/ipv4/tcp_output.c:3244
 tcp_push_pending_frames include/net/tcp.h:2360 [inline]
 tcp_data_snd_check net/ipv4/tcp_input.c:6075 [inline]
 tcp_rcv_established+0x1019/0x2800 net/ipv4/tcp_input.c:6658
 tcp_v4_do_rcv+0x903/0x13c0 net/ipv4/tcp_ipv4.c:1851
 sk_backlog_rcv include/net/sock.h:1190 [inline]
 __release_sock+0x265/0x3a0 net/core/sock.c:3216
 release_sock+0x190/0x260 net/core/sock.c:3815
 sk_stream_wait_memory+0x72b/0xf80 net/core/stream.c:149
 tcp_sendmsg_locked+0x238a/0x5360 net/ipv4/tcp.c:1405
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1452
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x5de/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __ia32_sys_sendto+0xdd/0x100 net/socket.c:2268
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fd801c
RSP: 002b:00000000f4c0e50c EFLAGS: 00000206 ORIG_RAX: 0000000000000171
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000080000580
RDX: 000000000000fdef RSI: 0000000010008095 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:kthreadd        state:R  running task     stack:26248 pid:2     tgid:2     ppid:0      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1821/0x5740 kernel/sched/core.c:7189
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d7/0x3c0 kernel/locking/lockdep.c:5893
Code: 8c 96 11 00 00 00 00 eb b5 e8 d5 5c 05 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 45 47 96 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c2 aa 91
RSP: 0018:ffffc90000077678 EFLAGS: 00000286
RAX: 7819994158171a00 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000001 RSI: ffffffff8e215d18 RDI: ffffffff8c28b760
RBP: ffff88801d69c9b8 R08: ffffffff823c8192 R09: ffffffff8e95cce0
R10: dffffc0000000000 R11: fffff94000139587 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8e95cce0 R15: ffff88801d69be00
 rcu_lock_release include/linux/rcupdate.h:310 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 page_ext_put+0xa3/0xc0 mm/page_ext.c:579
 __reset_page_owner+0x67/0x1f0 mm/page_owner.c:312
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0xc1c/0xd30 mm/page_alloc.c:2938
 __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_kmalloc+0x22/0xb0 mm/kasan/common.c:406
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5296 [inline]
 __kmalloc_noprof+0x35c/0x760 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 lsm_blob_alloc security/security.c:218 [inline]
 lsm_task_alloc security/security.c:270 [inline]
 security_task_alloc+0x4d/0x330 security/security.c:2785
 copy_process+0x1d12/0x4440 kernel/fork.c:2246
 kernel_clone+0x2d7/0x940 kernel/fork.c:2722
 kernel_thread+0x13f/0x1b0 kernel/fork.c:2783
 create_kthread kernel/kthread.c:459 [inline]
 kthreadd+0x4ec/0x6e0 kernel/kthread.c:817
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:syz-executor    state:R  running task     stack:24280 pid:5627  tgid:5627  ppid:5616   task_flags:0x40050c flags:0x08080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1821/0x5740 kernel/sched/core.c:7189
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
 spin_unlock include/linux/spinlock.h:390 [inline]
 zap_pte_range mm/memory.c:1964 [inline]
 zap_pmd_range mm/memory.c:2020 [inline]
 zap_pud_range mm/memory.c:2048 [inline]
 zap_p4d_range mm/memory.c:2069 [inline]
 __zap_vma_range+0x3d36/0x4b70 mm/memory.c:2109
 unmap_vmas+0x3ac/0x570 mm/memory.c:2178
 exit_mmap+0x280/0x9e0 mm/mmap.c:1300
 __mmput+0x118/0x430 kernel/fork.c:1178
 exit_mm+0x1f6/0x2d0 kernel/exit.c:582
 do_exit+0x6a2/0x22c0 kernel/exit.c:964
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 get_signal+0x1284/0x1330 kernel/signal.c:3037
 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0xa9/0x680 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_int80_emulation+0x31a/0x550 arch/x86/entry/syscall_32.c:175
 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:621
RIP: 0023:0xf71261ab
RSP: 002b:00000000ff994a7c EFLAGS: 00000246 ORIG_RAX: 0000000000000072
RAX: fffffffffffffe00 RBX: 00000000ffffffff RCX: 00000000ff994bbc
RDX: 0000000040000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 6330 jiffies! g24397 f0x2 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:27536 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 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
 </TASK>
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 syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
RIP: 0010:lock_acquire+0x123/0x350 kernel/locking/lockdep.c:5870
Code: 00 6a 00 55 ff 74 24 30 e8 da 02 00 00 48 83 c4 28 48 c7 c7 18 5d 21 8e e8 1a ad 05 0a b8 ff ff ff ff 65 0f c1 05 5d bf 96 11 <83> f8 01 0f 85 ae 00 00 00 9c 58 a9 00 02 00 00 0f 85 c1 00 00 00
RSP: 0000:ffffc90000a07cb8 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000101
RDX: 00000000a42637f2 RSI: ffffffff8e215d18 RDI: ffffffff8c28b760
RBP: ffffffff8176e256 R08: ffffffff8176e256 R09: ffffffff8e95cce0
R10: ffffc90000a07e78 R11: ffffffff81b0e210 R12: 0000000000000002
R13: ffffffff8e95cce0 R14: 0000000000000000 R15: 0000000000000246
FS:  0000000000000000(0000) GS:ffff88812539e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000080050018 CR3: 000000005a9f2000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 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_node_noprof+0x384/0x690 mm/slub.c:4951
 kmalloc_reserve net/core/skbuff.c:613 [inline]
 __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1385 [inline]
 synproxy_send_client_synack+0x172/0xe30 net/netfilter/nf_synproxy_core.c:463
 nft_synproxy_eval_v4+0x34a/0x4e0 net/netfilter/nft_synproxy.c:60
 nft_synproxy_do_eval+0x305/0x580 net/netfilter/nft_synproxy.c:142
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x48d/0x1ae0 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
 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
 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+0xaa3/0x1950 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
 </IRQ>
 <TASK>
 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: eb 7e 02 e9 d3 f8 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 b3 31 22 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0000:ffffc90000197e20 EFLAGS: 00000242
RAX: 000000000100b529 RBX: ffffffff819a858a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8dfa312d RDI: ffffffff8c28b760
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
 </TASK>