rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=f6a/1/0x4000000000000000 softirq=27077/27080 fqs=6 (t=10502 jiffies g=40325 q=375) rcu: rcu_preempt kthread starved for 10491 jiffies! g40325 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: rcu_preempt I28912 10 2 0x00004000 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x7d3/0xc40 kernel/sched/core.c:4155 NMI backtrace for cpu 1 CPU: 1 PID: 15053 Comm: syz-executor.3 Not tainted 5.8.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1f0/0x31e lib/dump_stack.c:118 nmi_cpu_backtrace+0x9f/0x180 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x199/0x2a0 kernel/rcu/tree_stall.h:320 print_cpu_stall kernel/rcu/tree_stall.h:553 [inline] check_cpu_stall kernel/rcu/tree_stall.h:627 [inline] rcu_pending kernel/rcu/tree.c:3471 [inline] rcu_sched_clock_irq+0x1a3f/0x1fd0 kernel/rcu/tree.c:2486 update_process_times+0x12c/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:176 [inline] tick_sched_timer+0x254/0x410 kernel/time/tick-sched.c:1320 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x42d/0x930 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1097 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0x133/0x230 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline] RIP: 0010:lock_acquire+0x1bf/0x720 kernel/locking/lockdep.c:4962 Code: c1 e8 03 80 3c 10 00 74 0c 48 c7 c7 f0 be 2b 89 e8 f6 f4 59 00 48 83 3d ee 60 d2 07 00 0f 84 09 05 00 00 48 8b 7c 24 10 57 9d <0f> 1f 44 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 50 0f 85 e0 RSP: 0018:ffffc900177eef38 EFLAGS: 00000282 RAX: 1ffffffff12577de RBX: 0000000000000000 RCX: 5210bde0a4938dac RDX: dffffc0000000000 RSI: ffff888046fb4b88 RDI: 0000000000000282 RBP: 1ffff11008df6961 R08: dffffc0000000000 R09: fffffbfff163329f R10: fffffbfff163329f R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffff888046fb4b0c R15: 0000000000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:241 rcu_read_lock include/linux/rcupdate.h:634 [inline] tipc_sk_lookup+0x85/0x7c0 net/tipc/socket.c:2970 tipc_sk_rcv+0x2b8/0x1940 net/tipc/socket.c:2461 tipc_node_xmit+0x257/0x10d0 net/tipc/node.c:1652 tipc_node_xmit_skb+0x110/0x150 net/tipc/node.c:1712 tipc_sk_rcv+0x16f4/0x1940 net/tipc/socket.c:2491 tipc_node_xmit+0x257/0x10d0 net/tipc/node.c:1652 tipc_sk_push_backlog net/tipc/socket.c:1303 [inline] tipc_sk_filter_connect net/tipc/socket.c:2226 [inline] tipc_sk_filter_rcv+0x1660/0x3ca0 net/tipc/socket.c:2335 tipc_sk_enqueue net/tipc/socket.c:2415 [inline] tipc_sk_rcv+0x6e1/0x1940 net/tipc/socket.c:2466 tipc_node_xmit+0x257/0x10d0 net/tipc/node.c:1652 tipc_node_xmit_skb net/tipc/node.c:1712 [inline] tipc_node_distr_xmit+0x2c7/0x3e0 net/tipc/node.c:1727 tipc_sk_backlog_rcv+0x12f/0x1b0 net/tipc/socket.c:2383 sk_backlog_rcv include/net/sock.h:996 [inline] __release_sock+0x1b2/0x480 net/core/sock.c:2550 release_sock+0x5d/0x1c0 net/core/sock.c:3066 tipc_release+0x1182/0x1440 net/tipc/socket.c:638 __sock_release net/socket.c:605 [inline] sock_close+0xd8/0x260 net/socket.c:1278 __fput+0x2f0/0x750 fs/file_table.c:281 task_work_run+0x137/0x1c0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:216 [inline] __prepare_exit_to_usermode+0x14c/0x1e0 arch/x86/entry/common.c:246 do_syscall_64+0x7f/0xe0 arch/x86/entry/common.c:368 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f9c0ee28c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000005 RBX: 00000000004dbf00 RCX: 000000000045cb19 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 00000000000000a4 R14: 00000000004c36a8 R15: 00007f9c0ee296d4