rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=80f/1/0x4000000000000000 softirq=32965/32970 fqs=0 (t=10500 jiffies g=53437 q=43) rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g53437 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=17463 rcu: rcu_preempt kthread starved for 10500 jiffies! g53437 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:28656 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1088 Comm: kworker/u4:5 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:radix_tree_lookup+0x2/0x20 lib/radix-tree.c:816 Code: 44 24 58 65 48 2b 04 25 28 00 00 00 75 11 48 83 c4 60 4c 89 e0 5b 5d 41 5c c3 49 89 c4 eb c8 e8 54 ea 44 05 0f 1f 40 00 41 54 <49> 89 f4 55 48 89 fd e8 52 78 78 fd 4c 89 e6 48 89 ef 5d 41 5c 31 RSP: 0018:ffffc90005277bd8 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000074d17f2e RCX: 0000000000000000 RDX: 1ffff1100d7d6a8a RSI: 0000000074d17f2e RDI: ffff88806beb5400 RBP: ffff88806beb5400 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff88ba7ee9 R11: 0000000000000000 R12: ffff88806beb5458 R13: ffffed100d7d6a93 R14: ffff88806c37b000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3fa3fa9004 CR3: 000000004fef5000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tipc_topsrv_stop net/tipc/topsrv.c:691 [inline] tipc_topsrv_exit_net+0x20a/0x5d0 net/tipc/topsrv.c:715 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:168 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1088 Comm: kworker/u4:5 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x70 kernel/kcov.c:286 Code: b7 c9 48 83 c2 01 48 c7 44 30 e0 02 00 00 00 48 89 7c 30 e8 48 89 4c 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 <41> 89 f8 bf 03 00 00 00 4c 8b 14 24 89 f1 65 48 8b 34 25 40 70 02 RSP: 0018:ffffc90005277b80 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801c2f5700 RSI: 0000000000000000 RDI: 000000000000003f RBP: dffffc0000000000 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffff83ff1e15 R11: 0000000000000000 R12: ffff88802a78de42 R13: 0000000000000000 R14: 0000000074f9f17b R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3fa3fa9004 CR3: 000000004fef5000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: shift_maxindex lib/radix-tree.c:211 [inline] node_maxindex lib/radix-tree.c:216 [inline] radix_tree_load_root lib/radix-tree.c:395 [inline] __radix_tree_lookup+0xb4/0x2a0 lib/radix-tree.c:756 tipc_topsrv_stop net/tipc/topsrv.c:691 [inline] tipc_topsrv_exit_net+0x20a/0x5d0 net/tipc/topsrv.c:715 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:168 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 NMI backtrace for cpu 1 CPU: 1 PID: 18563 Comm: kworker/u4:8 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: tipc_rcv tipc_conn_recv_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1001 Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 73 56 4a 00 eb 07 0f 00 2d ea 8f 75 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 36 51 4a 00 8b 74 24 0c RSP: 0018:ffffc90004c47b08 EFLAGS: 00000206 RAX: 000000000005533a RBX: 0000000000000000 RCX: 1ffffffff1ffafee RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000 RBP: ffff88806beb5458 R08: 0000000000000001 R09: ffffffff8ff72b0f R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: ffffed100d7d6a8b R14: 0000000000000001 R15: ffff8880b9d3a880 pv_wait arch/x86/include/asm/paravirt.h:603 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x8b8/0xb40 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:115 spin_lock_bh include/linux/spinlock.h:354 [inline] tipc_conn_kref_release+0x47/0x380 net/tipc/topsrv.c:129 kref_put include/linux/kref.h:65 [inline] conn_put net/tipc/topsrv.c:147 [inline] tipc_conn_recv_work+0x14a/0x190 net/tipc/topsrv.c:430 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 44 24 58 rex.R and $0x58,%al 3: 65 48 2b 04 25 28 00 sub %gs:0x28,%rax a: 00 00 c: 75 11 jne 0x1f e: 48 83 c4 60 add $0x60,%rsp 12: 4c 89 e0 mov %r12,%rax 15: 5b pop %rbx 16: 5d pop %rbp 17: 41 5c pop %r12 19: c3 retq 1a: 49 89 c4 mov %rax,%r12 1d: eb c8 jmp 0xffffffe7 1f: e8 54 ea 44 05 callq 0x544ea78 24: 0f 1f 40 00 nopl 0x0(%rax) 28: 41 54 push %r12 * 2a: 49 89 f4 mov %rsi,%r12 <-- trapping instruction 2d: 55 push %rbp 2e: 48 89 fd mov %rdi,%rbp 31: e8 52 78 78 fd callq 0xfd787888 36: 4c 89 e6 mov %r12,%rsi 39: 48 89 ef mov %rbp,%rdi 3c: 5d pop %rbp 3d: 41 5c pop %r12 3f: 31 .byte 0x31