rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10336/1:b..l rcu: (detected by 1, t=10503 jiffies, g=68277, q=1595106 ncpus=2) task:syz-executor state:R running task stack:21728 pid:10336 tgid:10336 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0xc/0x550 kernel/locking/lockdep.c:5793 Code: c0 c3 cc cc cc cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 41 56 <41> 55 41 54 53 48 83 e4 e0 48 81 ec 20 01 00 00 4c 89 4c 24 28 4c RSP: 0018:ffffc90003c6f7e0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffea0000bda1c0 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e937de0 RBP: ffffc90003c6f7f0 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10052d4062 R12: 0000000000000000 R13: ffffea0000bda1c8 R14: ffffffff820b6530 R15: 1ffffd400017b438 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1109 [inline] free_unref_page+0xd0f/0xf20 mm/page_alloc.c:2638 vfree+0x186/0x2e0 mm/vmalloc.c:3361 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x28/0x50 kernel/kcov.c:535 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f889a3b00e5 RSP: 002b:00007f889a65fd50 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 0000000000000008 RCX: 00007f889a3b00e5 RDX: 00007f889a65fd90 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f889a65fdec R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000064 R13: 0000000000080c27 R14: 000000000007df79 R15: 00007f889a65fe40 rcu: rcu_preempt kthread starved for 10475 jiffies! g68277 f0x2 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:25720 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5285 Comm: kworker/0:7 Not tainted 6.12.0-rc2-syzkaller-00307-g36c254515dc6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: wg-crypt-wg1 wg_packet_encrypt_worker RIP: 0010:__lock_acquire+0x1d4/0x2050 Code: 98 e0 0a 00 00 83 fa 31 0f 83 50 1c 00 00 48 8d 04 92 4c 8d 6c c3 f8 4c 89 eb 48 c1 eb 03 0f b6 04 33 84 c0 0f 85 d5 16 00 00 <48> 83 bc 24 c8 00 00 00 00 0f 84 e8 00 00 00 45 8b 65 00 44 89 e0 RSP: 0018:ffffc90000006c10 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffff11005cde8ef RCX: ffffffff9a3ce903 RDX: 0000000000000004 RSI: dffffc0000000000 RDI: 0000000000000001 RBP: ffff88802e6f46d8 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff2039e5e R12: ffff88802e6f3c00 R13: ffff88802e6f4778 R14: 0000000000000000 R15: ffffffff9a6817c8 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f20d11fff8c CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000002800 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_active_state+0x15d/0x360 lib/debugobjects.c:936 debug_rcu_head_queue kernel/rcu/rcu.h:225 [inline] __call_rcu_common kernel/rcu/tree.c:3071 [inline] call_rcu+0xb5/0xa70 kernel/rcu/tree.c:3190 refdst_drop include/net/dst.h:263 [inline] skb_dst_drop include/net/dst.h:275 [inline] skb_release_head_state+0x73/0x250 net/core/skbuff.c:1174 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb+0x60/0xf0 net/core/skbuff.c:1436 nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c5/0x980 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+0x1561/0x1610 drivers/net/wireguard/send.c:293 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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