rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=926c/1/0x4000000000000000 softirq=9134/9135 fqs=45 rcu: (detected by 1, t=10502 jiffies, g=9921, q=1095 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5157 Comm: kworker/0:4 Not tainted 6.10.0-syzkaller-09703-gd7e78951a8b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3762 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3781 [inline] RIP: 0010:validate_chain+0x1e6/0x5900 kernel/locking/lockdep.c:3836 Code: 89 df e8 0d 56 89 00 48 89 5c 24 48 48 8b 1b 48 85 db 74 48 48 83 c3 f8 74 42 4c 8d 7b 18 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 ff e8 e0 55 89 00 49 8b 07 4c 39 f0 0f 84 7e 03 00 00 RSP: 0018:ffffc90000006400 EFLAGS: 00000046 RAX: 1ffffffff26125eb RBX: ffffffff93092f40 RCX: ffffffff81702f7e RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92ff0608 RBP: ffffc90000006700 R08: ffffffff92ff060f R09: 1ffffffff25fe0c1 R10: dffffc0000000000 R11: fffffbfff25fe0c2 R12: dffffc0000000000 R13: ffff88802b2e0ba0 R14: d6bf87c490213bdc R15: ffffffff93092f58 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f76f7df3fc8 CR3: 000000007da38000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1693 [inline] __hrtimer_run_queues+0x670/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:write_comp_data kernel/kcov.c:236 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x2d/0x90 kernel/kcov.c:311 Code: fa 4c 8b 04 24 65 48 8b 0c 25 80 d5 03 00 65 8b 05 90 86 70 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 57 83 b9 1c 16 00 00 00 <74> 4e 8b 81 f8 15 00 00 83 f8 03 75 43 48 8b 91 00 16 00 00 44 8b RSP: 0018:ffffc90000006d60 EFLAGS: 00000246 RAX: 0000000080000102 RBX: ffffc90000006e88 RCX: ffff88802b2e0000 RDX: ffffc90000006e75 RSI: ffffffff815e1d7b RDI: 0000000000000000 RBP: ffffffff815e1d7c R08: ffffffff814118fc R09: ffffc90000006f30 R10: 0000000000000003 R11: ffffffff817ef0e0 R12: ffffc90000006e40 R13: ffffc90000006e90 R14: dffffc0000000000 R15: ffffffff815e1d7c orc_find arch/x86/kernel/unwind_orc.c:202 [inline] unwind_next_frame+0x1ac/0x2a00 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2235 [inline] slab_free mm/slub.c:4464 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4539 skb_kfree_head net/core/skbuff.c:1082 [inline] skb_free_head net/core/skbuff.c:1096 [inline] skb_release_data+0x64d/0x880 net/core/skbuff.c:1123 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1202 [inline] sk_skb_reason_drop+0x1a5/0x3d0 net/core/skbuff.c:1240 geneve_udp_encap_recv+0x90d/0x2df0 udp_queue_rcv_one_skb+0x1616/0x1820 net/ipv4/udp.c:2132 udp_unicast_rcv_skb+0x253/0x3d0 net/ipv4/udp.c:2370 __udp4_lib_rcv+0x135d/0x2710 net/ipv4/udp.c:2446 ip_protocol_deliver_rcu+0x28d/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5660 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5774 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_encrypt_worker+0x2e8/0x1610 drivers/net/wireguard/send.c:293 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10263 jiffies! g9921 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:25560 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 53 Comm: kworker/u8:3 Not tainted 6.10.0-syzkaller-09703-gd7e78951a8b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline] RIP: 0010:smp_call_function_many_cond+0x1860/0x29d0 kernel/smp.c:856 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 89 14 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 34 10 0c 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 18 10 RSP: 0018:ffffc90000bd7700 EFLAGS: 00000293 RAX: ffffffff818739e8 RBX: 1ffff11017288c29 RCX: ffff88801d28bc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000bd78e0 R08: ffffffff818739b7 R09: 1ffffffff25fe0c0 R10: dffffc0000000000 R11: fffffbfff25fe0c1 R12: dffffc0000000000 R13: ffff8880b9446148 R14: ffff8880b953f9c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa5dd435000 CR3: 000000000e134000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x726/0xb30 arch/x86/kernel/alternative.c:2357 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244