IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready INFO: task syz-executor0:4321 blocked for more than 140 seconds. Not tainted 4.4.139-g7ba5557 #2 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D ffff8800ac6b79c8 28144 4321 3971 0x20020004 ffff8800ac6b79c8 0000000000000000 ffff8801d44138e0 ffffed003a88271b ffff8801d4413000 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8 ffff8801db21f4c0 ffffffff84417840 ffff8801d4413000 0000000000000000 Call Trace: [] schedule+0x7a/0x1b0 kernel/sched/core.c:3359 [] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3392 [] __mutex_lock_common kernel/locking/mutex.c:582 [inline] [] mutex_lock_nested+0x307/0x850 kernel/locking/mutex.c:621 [] lo_ioctl+0x8b/0x1ad0 drivers/block/loop.c:1355 [] lo_compat_ioctl+0xb2/0x140 drivers/block/loop.c:1551 [] compat_blkdev_ioctl+0x395/0x3a10 block/compat_ioctl.c:751 [] C_SYSC_ioctl fs/compat_ioctl.c:1592 [inline] [] compat_SyS_ioctl+0x484/0x2270 fs/compat_ioctl.c:1544 [] do_syscall_32_irqs_on arch/x86/entry/common.c:392 [inline] [] do_fast_syscall_32+0x326/0x8b0 arch/x86/entry/common.c:459 [] sysenter_flags_fixed+0xd/0x17 1 lock held by syz-executor0/4321: #0: (&lo->lo_ctl_mutex/1){+.+.+.}, at: [] lo_ioctl+0x8b/0x1ad0 drivers/block/loop.c:1355 Sending NMI to all CPUs: NMI backtrace for cpu 0 CPU: 0 PID: 492 Comm: khungtaskd Not tainted 4.4.139-g7ba5557 #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d8d70000 task.stack: ffff8801d8d30000 RIP: 0010:[] [] native_apic_mem_write arch/x86/include/asm/apic.h:94 [inline] RIP: 0010:[] [] __default_send_IPI_dest_field arch/x86/include/asm/ipi.h:119 [inline] RIP: 0010:[] [] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:61 [inline] RIP: 0010:[] [] flat_send_IPI_mask+0xf6/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69 RSP: 0018:ffff8801d8d37cc8 EFLAGS: 00000046 RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000 RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300 RBP: ffff8801d8d37cf0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000246 R13: 0000000000000003 R14: 0000000000000002 R15: ffffffff8446f6a0 FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1488bf6000 CR3: 00000001d3ab6000 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff8446f6a0 ffffffff84a18ca0 0000000000000007 fffffbfff0942c44 0000000000000040 ffff8801d8d37d10 ffffffff810b5b01 ffffffff83c0b2a0 0000000000000003 ffff8801d8d37d68 ffffffff81e18603 ffffffff8140dd6f Call Trace: [] nmi_raise_cpu_backtrace+0x61/0x80 arch/x86/kernel/apic/hw_nmi.c:33 [] nmi_trigger_all_cpu_backtrace.cold.4+0x70/0xad lib/nmi_backtrace.c:85 [] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 [] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog.cold.1+0xd3/0xee kernel/hung_task.c:238 [] kthread+0x268/0x300 kernel/kthread.c:211 [] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:510 Code: b3 5f ff f6 c4 10 75 e2 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 f2 09 da 80 cf 04 41 83 fe 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 75 1a 4c 89 e7 57 9d 0f 1f 44 00 00 e8 e2 NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.139-g7ba5557 #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d9a41800 task.stack: ffff8801d9a50000 RIP: 0010:[] [] trace_hardirqs_on_caller+0xf6/0x590 kernel/locking/lockdep.c:2595 RSP: 0018:ffff8801d9a57db8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff8592e600 RCX: 1ffffffff0942961 RDX: 0000000000000004 RSI: ffffffff81e6d11b RDI: ffff8801d9a420a8 RBP: ffff8801d9a57dc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff81281d79 R13: 0000000000000000 R14: fffffbfff07488e8 R15: ffffffff84a05d68 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006c47e4 CR3: 00000001d3ab6000 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffff8801db318570 0000000000000296 ffff8801d9a57dd8 ffffffff8122eacd ffff8801d9a57e00 ffffffff81281d79 ffff8801d9a57e00 dffffc0000000000 0000000000000000 ffff8801d9a57ea8 ffffffff8121bf64 fffffbfff0942a2e Call Trace: [] trace_hardirqs_on+0xd/0x10 kernel/locking/lockdep.c:2619 [] rcu_idle_exit+0xb9/0x100 kernel/rcu/tree.c:852 [] cpu_idle_poll kernel/sched/idle.c:67 [inline] [] cpu_idle_loop kernel/sched/idle.c:251 [inline] [] cpu_startup_entry+0x264/0x780 kernel/sched/idle.c:301 [] start_secondary+0x324/0x400 arch/x86/kernel/smpboot.c:242 Code: 45 85 d2 0f 85 a5 02 00 00 48 c7 c3 00 e6 92 85 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 <83> c0 03 38 d0 7c 08 84 d2 0f 85 2a 03 00 00 44 8b 0d c4 ff 6f