rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10480 ticks this GP) idle=ba6/1/0x4000000000000000 softirq=7474/7474 fqs=0 (t=10500 jiffies g=7061 q=4) rcu: rcu_preempt kthread starved for 10500 jiffies! g7061 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:28880 pid: 13 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8de/0x2170 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x11b/0x210 kernel/time/timer.c:1878 rcu_gp_fqs_loop kernel/rcu/tree.c:1940 [inline] rcu_gp_kthread+0xbbe/0x1d90 kernel/rcu/tree.c:2113 kthread+0x36f/0x450 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 NMI backtrace for cpu 0 CPU: 0 PID: 5907 Comm: syz-executor.0 Not tainted 5.11.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x9a/0xcc lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x30/0x99 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x11f/0x170 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x1f4/0x230 kernel/rcu/tree_stall.h:337 print_cpu_stall kernel/rcu/tree_stall.h:569 [inline] check_cpu_stall kernel/rcu/tree_stall.h:643 [inline] rcu_pending kernel/rcu/tree.c:3751 [inline] rcu_sched_clock_irq.cold+0x48e/0xedf kernel/rcu/tree.c:2580 update_process_times+0x13b/0x1c0 kernel/time/timer.c:1782 tick_sched_handle+0x6f/0x130 kernel/time/tick-sched.c:226 tick_sched_timer+0x132/0x210 kernel/time/tick-sched.c:1369 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x18a/0xb00 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x300/0x930 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1106 asm_call_irq_on_stack+0xf/0x20 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline] run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline] sysvec_apic_timer_interrupt+0xbd/0x100 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:629 RIP: 0010:lock_acquire+0x1d2/0x720 kernel/locking/lockdep.c:5410 Code: 48 c7 c7 a0 e7 8a 88 48 83 c4 20 e8 08 2b de 06 b8 ff ff ff ff 65 0f c1 05 3b 04 b1 7e 83 f8 01 0f 85 da 03 00 00 ff 34 24 9d <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000181efa8 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 1ffff92000303df7 RCX: 1ffff92000303dde RDX: 1ffff11002d1913b RSI: ffffffff888ae7a0 RDI: ffffffff88ddb560 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8e1478b7 R10: fffffbfff1c28f16 R11: 615f6e616d746162 R12: 0000000000000000 R13: ffff8880251fbd98 R14: 0000000000000000 R15: 0000000000000000 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] batadv_tt_local_purge_pending_clients+0xf2/0x3b0 net/batman-adv/translation-table.c:3683 batadv_tt_local_resize_to_mtu+0x80/0xe0 net/batman-adv/translation-table.c:3986 batadv_hardif_activate_interface.part.0.cold+0x141/0x1b4 net/batman-adv/hard-interface.c:655 batadv_hardif_activate_interface net/batman-adv/hard-interface.c:802 [inline] batadv_hardif_enable_interface+0x96b/0xa30 net/batman-adv/hard-interface.c:794 batadv_softif_slave_add+0x7a/0xf0 net/batman-adv/soft-interface.c:858 __rtnl_newlink+0xe8d/0x1320 net/core/rtnetlink.c:3460 rtnl_newlink+0x5a/0x90 net/core/rtnetlink.c:3491 rtnetlink_rcv_msg+0x32f/0x860 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x118/0x370 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x42e/0x700 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x70e/0xbe0 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:672 ____sys_sendmsg+0x5bf/0x7a0 net/socket.c:2345 ___sys_sendmsg+0xd3/0x150 net/socket.c:2399 __sys_sendmsg+0xb2/0x140 net/socket.c:2432 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fb5ef007109 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb5ee77c168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb5ef119f60 RCX: 00007fb5ef007109 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00007fb5ef06105d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff99642e7f R14: 00007fb5ee77c300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 48 c7 c7 a0 e7 8a 88 mov $0xffffffff888ae7a0,%rdi 7: 48 83 c4 20 add $0x20,%rsp b: e8 08 2b de 06 callq 0x6de2b18 10: b8 ff ff ff ff mov $0xffffffff,%eax 15: 65 0f c1 05 3b 04 b1 xadd %eax,%gs:0x7eb1043b(%rip) # 0x7eb10458 1c: 7e 1d: 83 f8 01 cmp $0x1,%eax 20: 0f 85 da 03 00 00 jne 0x400 26: ff 34 24 pushq (%rsp) 29: 9d popfq * 2a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 31: fc ff df 34: 48 01 c3 add %rax,%rbx 37: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 3e: 48 rex.W 3f: c7 .byte 0xc7