INFO: task syz-executor4:9175 blocked for more than 120 seconds. Not tainted 4.4.118-g5f7f76a #24 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D ffff8800b1ee7ad8 29896 9175 3863 0x00000004 ffff8800b1ee7ad8 0000000000000006 ffff8801d2fb4800 ffffffff8113bd3a ffffed00157122e8 ffff8800ab891700 ffff8801db21fdb8 ffff8801db21fde0 ffff8801db21f4d8 ffff8800ac569800 ffff8801d2fb4800 0000000000000000 Call Trace: [] schedule+0x7a/0x1b0 kernel/sched/core.c:3353 [] __lock_sock+0xf1/0x180 net/core/sock.c:1999 [] lock_sock_nested+0xf6/0x120 net/core/sock.c:2453 [] lock_sock include/net/sock.h:1493 [inline] [] ipv6_getorigdst+0x136/0x610 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c:238 [] nf_sockopt net/netfilter/nf_sockopt.c:103 [inline] [] nf_getsockopt+0x6a/0xc0 net/netfilter/nf_sockopt.c:121 [] ipv6_getsockopt+0x1ce/0x250 net/ipv6/ipv6_sockglue.c:1344 [] tcp_getsockopt+0x82/0xd0 net/ipv4/tcp.c:2945 [] sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2618 [] SYSC_getsockopt net/socket.c:1798 [inline] [] SyS_getsockopt+0x14a/0x230 net/socket.c:1780 [] entry_SYSCALL_64_fastpath+0x1c/0x98 1 lock held by syz-executor4/9175: #0: (sk_lock-AF_INET6){+.+.+.}, at: [] lock_sock include/net/sock.h:1493 [inline] #0: (sk_lock-AF_INET6){+.+.+.}, at: [] ipv6_getsockopt+0x1b3/0x250 net/ipv6/ipv6_sockglue.c:1343 Sending NMI to all CPUs: NMI backtrace for cpu 0 CPU: 0 PID: 486 Comm: khungtaskd Not tainted 4.4.118-g5f7f76a #24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8800bb2d0000 task.stack: ffff8800bbba8000 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+0xf7/0x1a0 arch/x86/kernel/apic/apic_flat_64.c:69 RSP: 0018:ffff8800bbbafcb8 EFLAGS: 00000046 RAX: 0000000003000000 RBX: 0000000000000c00 RCX: 0000000000000000 RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fb300 RBP: ffff8800bbbafce0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000246 R13: 0000000000000003 R14: ffffffff8426f420 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6cf5a47000 CR3: 00000000ac740000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff8426f420 ffffffff847ef9c0 fffffbfff08fd9ec dffffc0000000000 ffff8801db31bca0 ffff8800bbbafd00 ffffffff810b999b ffffffff839f63c0 0000000000000003 ffff8800bbbafd60 ffffffff81d0ef94 ffffffff8141b013 Call Trace: [] nmi_raise_cpu_backtrace+0x5b/0x70 arch/x86/kernel/apic/hw_nmi.c:33 [] nmi_trigger_all_cpu_backtrace+0x4a4/0x550 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+0x6fa/0xae0 kernel/hung_task.c:238 [] kthread+0x268/0x300 kernel/kthread.c:211 [] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:506 Code: b3 5f ff f6 c4 10 75 e1 44 89 e8 c1 e0 18 89 04 25 10 b3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 b3 5f ff <41> f7 c4 00 02 00 00 74 1a e8 6b 2f 17 00 4c 89 e7 57 9d 0f 1f NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.118-g5f7f76a #24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d9b49800 task.stack: ffff8801d9b58000 RIP: 0010:[] [] native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:49 RSP: 0018:ffff8801d9b5fd98 EFLAGS: 00000246 RAX: 0000000000000007 RBX: ffffffff847ddac8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801d9b4a0cc RBP: ffff8801d9b5fd98 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: fffffbfff070889c R14: ffffffff847ebe38 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f32080119b8 CR3: 00000000ac740000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffff8801d9b5fdd0 ffffffff81027e85 ffff8801d9b60000 ffffffff847ddac8 fffffbfff070889c ffffffff847ebe38 0000000000000000 ffff8801d9b5fde0 ffffffff810293fa ffff8801d9b5fdf8 ffffffff81221468 dffffc0000000000 Call Trace: [] arch_safe_halt arch/x86/include/asm/paravirt.h:117 [inline] [] default_idle+0x55/0x3c0 arch/x86/kernel/process.c:290 [] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:281 [] default_idle_call+0x48/0x70 kernel/sched/idle.c:93 [] cpuidle_idle_call kernel/sched/idle.c:157 [inline] [] cpu_idle_loop kernel/sched/idle.c:253 [inline] [] cpu_startup_entry+0x5fd/0x8f0 kernel/sched/idle.c:301 [] start_secondary+0x304/0x3e0 arch/x86/kernel/smpboot.c:242 Code: 00 00 00 00 00 55 48 89 e5 fa 5d c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 fb 5d c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 fb f4 <5d> c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 f4 5d c3 66 0f 1f 84