rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=d45c/1/0x4000000000000000 softirq=8312/8313 fqs=1 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3006/1:b..l (detected by 0, t=11754 jiffies, g=7537, q=863 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3660 Comm: kworker/1:3 Not tainted 6.0.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: wg-kex-wg1 wg_packet_handshake_receive_worker RIP: 0010:pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:596 [inline] RIP: 0010:queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline] RIP: 0010:do_raw_spin_unlock+0x16c/0x230 kernel/locking/spinlock_debug.c:141 Code: 08 ff ff ff ff 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 b6 00 00 00 48 83 3d f1 16 aa 09 00 74 4b 48 89 ef 2f d8 ff ff 90 5d 41 5c 41 5d c3 48 c7 c6 40 28 0c 89 48 89 ef RSP: 0018:ffffc900003f8da0 EFLAGS: 00000082 RAX: 1ffffffff15fef19 RBX: ffff88805f55fb40 RCX: ffffffff815560c0 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff88805f55fae8 RBP: ffff88805f55fae8 R08: 0000000000000000 R09: ffff88805f55faeb R10: ffffed100beabf5d R11: 0000000000000000 R12: ffff88805f55faf0 R13: ffff88805f55faf8 R14: ffff88805f55fae8 R15: ffff88801e5dd100 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e9360aeaa0 CR3: 00000000200db000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_unlock+0x1a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:389 [inline] advance_sched+0x37a/0x920 net/sched/sch_taprio.c:765 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4d7/0xb00 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x2f5/0x780 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:fsqr2+0x2e5/0x360 arch/x86/crypto/curve25519-x86_64.c:783 Code: 00 48 c7 c2 26 00 00 00 c4 62 bb f6 6e 60 31 c9 f3 4c 0f 38 f6 46 40 c4 e2 b3 f6 5e 68 66 4d 0f 38 f6 cd f3 4c 0f 38 f6 4e 48 62 ab f6 6e 70 66 4c 0f 38 f6 d3 f3 4c 0f 38 f6 56 50 c4 e2 a3 RSP: 0018:ffffc90002dbf4b0 EFLAGS: 00000a46 RAX: 0000000000000000 RBX: 000000000000000f RCX: 0000000000000000 RDX: 0000000000000026 RSI: ffffc90002dbf590 RDI: ffffc90002dbf6f0 RBP: ffffc90002dbf6f0 R08: 5d244895d81459ca R09: 01d6bf6bb3cc969e R10: cc5a1e0d820273b7 R11: 9751c997701fdefb R12: ffffc90002dbf6f0 R13: 000000000000001a R14: 2759c11f98eb5b77 R15: 0000000000000000 point_add_and_double+0x2e8/0x610 arch/x86/crypto/curve25519-x86_64.c:1015 montgomery_ladder.constprop.0+0x370/0x540 arch/x86/crypto/curve25519-x86_64.c:1098 curve25519_ever64 arch/x86/crypto/curve25519-x86_64.c:1252 [inline] curve25519_arch+0x20d/0x350 arch/x86/crypto/curve25519-x86_64.c:1599 curve25519 include/crypto/curve25519.h:39 [inline] mix_dh+0x6e/0x100 drivers/net/wireguard/noise.c:411 wg_noise_handshake_create_response+0x32d/0x570 drivers/net/wireguard/noise.c:702 wg_packet_send_handshake_response+0xbe/0x2a0 drivers/net/wireguard/send.c:94 wg_receive_handshake_packet+0x1ce/0x9a0 drivers/net/wireguard/receive.c:154 wg_packet_handshake_receive_worker+0x10f/0x350 drivers/net/wireguard/receive.c:213 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x294/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 task:udevd state:R running task stack:26576 pid: 3006 ppid: 1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0x916/0x27c0 kernel/sched/core.c:6494 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6806 irqentry_exit+0x31/0x80 kernel/entry/common.c:428 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x1ef/0x570 kernel/locking/lockdep.c:5634 Code: 90 ad 7e 83 f8 01 0f 85 e8 02 00 00 9c 58 f6 c4 02 0f 85 fb 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90002c5f7d8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200058befd RCX: 6b3eed10b5b7c606 RDX: 1ffff1100f8e0d7e RSI: ffffffff890bc380 RDI: ffffffff89643020 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8f3bf887 R10: fffffbfff1e77f10 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8b17acc0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:280 [inline] rcu_read_lock include/linux/rcupdate.h:706 [inline] dput+0x63/0xa00 fs/dcache.c:899 step_into+0xba6/0x1d60 fs/namei.c:1846 link_path_walk.part.0+0x53e/0xab0 fs/namei.c:2320 link_path_walk fs/namei.c:2244 [inline] path_lookupat+0x6d/0x660 fs/namei.c:2473 filename_lookup+0x19f/0x510 fs/namei.c:2503 vfs_statx+0xe2/0x2e0 fs/stat.c:228 vfs_fstatat+0x4f/0x70 fs/stat.c:255 __do_sys_newfstatat+0x72/0xd0 fs/stat.c:425 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6a815251da RSP: 002b:00007ffee3a99b48 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000055e9360ca370 RCX: 00007f6a815251da RDX: 00007ffee3a99b58 RSI: 00007ffee3a99fe8 RDI: 00000000ffffff9c RBP: 00007ffee3a99be8 R08: 0000000000000000 R09: 000055e9360bdc80 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffee3a99fe8 R13: 00007ffee3a99b58 R14: 000055e9360912c0 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 2973 jiffies! g7537 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=4728 rcu: rcu_preempt kthread starved for 2974 jiffies! g7537 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28928 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0x916/0x27c0 kernel/sched/core.c:6494 schedule+0xda/0x1b0 kernel/sched/core.c:6570 schedule_timeout+0x11d/0x250 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1657 rcu_gp_kthread+0x236/0x360 kernel/rcu/tree.c:1854 kthread+0x294/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 3659 Comm: kworker/0:4 Not tainted 6.0.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: events_power_efficient neigh_periodic_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x30/0xca lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x154/0x180 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:514 print_other_cpu_stall kernel/rcu/tree_stall.h:619 [inline] check_cpu_stall kernel/rcu/tree_stall.h:762 [inline] rcu_pending kernel/rcu/tree.c:3660 [inline] rcu_sched_clock_irq+0x2404/0x2530 kernel/rcu/tree.c:2342 update_process_times+0xe4/0x160 kernel/time/timer.c:1839 tick_sched_handle+0x6f/0x130 kernel/time/tick-sched.c:243 tick_sched_timer+0xaa/0xd0 kernel/time/tick-sched.c:1480 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x18a/0xb00 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x2f5/0x780 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:debug_write_lock_before kernel/locking/spinlock_debug.c:187 [inline] RIP: 0010:do_raw_write_lock+0xc6/0x280 kernel/locking/spinlock_debug.c:209 Code: 3c 02 00 0f 85 b5 01 00 00 65 48 8b 04 25 80 6f 02 00 48 39 43 10 0f 84 3c 01 00 00 48 8d 6b 0c 48 b8 00 00 00 00 00 fc ff df <48> 89 ea 48 c1 ea 03 0f b6 14 02 48 89 e8 83 e0 07 83 c0 03 38 d0 RSP: 0018:ffffc90002dafc20 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: ffff88807bcff028 RCX: 0000000000000000 RDX: 1ffff1100f79fe07 RSI: ffffffff890bc380 RDI: ffff88807bcff030 RBP: ffff88807bcff034 R08: 0000000000000000 R09: ffffffff8f3bf947 R10: fffffbfff1e77f28 R11: 0000000000000000 R12: 1ffff920005b5f85 R13: ffff88807bcff038 R14: ffff88807bcff000 R15: ffffffff8ca66ad8 neigh_periodic_work+0x243/0x8a0 net/core/neighbour.c:970 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x294/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306