rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=0c2/1/0x4000000000000004 softirq=475507/475508 fqs=5172 rcu: (t=10500 jiffies g=384425 q=91) NMI backtrace for cpu 0 CPU: 0 PID: 8356 Comm: syz-executor.2 Not tainted 4.19.169-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+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x15f/0x19c kernel/rcu/tree.c:1340 print_cpu_stall kernel/rcu/tree.c:1478 [inline] check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0x62d/0xe19 kernel/rcu/tree.c:2682 update_process_times+0x2a/0x70 kernel/time/timer.c:1650 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:192 Code: c0 98 81 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d d1 63 db 01 00 74 25 fb 66 0f 1f 44 00 00 01 00 00 00 e8 f6 4f 2b f9 65 8b 05 2f c1 eb 77 85 c0 74 02 5d RSP: 0018:ffff8880ba007dd0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3033 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff8880af066ec4 RBP: ffff8880ba022b00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8686a350 R13: ffff8880ba022b00 R14: ffff8880ba007e68 R15: 0000000000000000 expire_timers+0x238/0x4e0 kernel/time/timer.c:1374 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:545 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:mntput_no_expire+0x2/0xa30 fs/namespace.c:1120 Code: e9 01 ff ff ff e8 fe c6 ed ff e9 d5 fe ff ff 4c 89 f7 e8 f1 c6 ed ff e9 a2 fe ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 83 ec 20 e8 0a 0e b8 ff e8 45 RSP: 0018:ffff888036717958 EFLAGS: 00000212 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: ffff8880a2e35820 RCX: ffffc9000a455000 RDX: 0000000000001b8a RSI: ffffffff81aa56bf RDI: ffff8880a2e35800 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000000 R12: ffff8880a2e35800 R13: ffff888036717ce8 R14: ffff8880277afe20 R15: ffff8880a2e35820 mntput+0x67/0x90 fs/namespace.c:1187 path_to_nameidata fs/namei.c:840 [inline] step_into fs/namei.c:1777 [inline] walk_component+0x515/0xda0 fs/namei.c:1830 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1db/0x2df0 fs/namei.c:3536 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45e219 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fceffd8cc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045e219 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000380 RBP: 000000000119c108 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c0dc R13: 00007fffa7d65eff R14: 00007fceffd8d9c0 R15: 000000000119c0dc nla_parse: 2 callbacks suppressed netlink: 21556 bytes leftover after parsing attributes in process `syz-executor.1'. bridge0: port 505(vlan523) entered blocking state bridge0: port 505(vlan523) entered disabled state device vlan523 entered promiscuous mode Left network mode Left network mode Left network mode IPVS: ftp: loaded support on port[0] = 21 chnl_net:caif_netlink_parms(): no params data found bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered disabled state device bridge_slave_0 entered promiscuous mode bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_1 entered promiscuous mode bond0: Enslaving bond_slave_0 as an active interface with an up link bond0: Enslaving bond_slave_1 as an active interface with an up link IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready team0: Port device team_slave_0 added IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready team0: Port device team_slave_1 added Bluetooth: hci0: command 0x0409 tx timeout batman_adv: batadv0: Adding interface: batadv_slave_0 batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active