INFO: task kworker/0:4:8038 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-next-20200701-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D27808 8038 2 0x00004000 Workqueue: afs afs_manage_cell Call Trace: context_switch kernel/sched/core.c:3445 [inline] __schedule+0x8b4/0x1e80 kernel/sched/core.c:4169 schedule+0xd0/0x2a0 kernel/sched/core.c:4244 bit_wait+0x12/0xa0 kernel/sched/wait_bit.c:199 __wait_on_bit+0x60/0x190 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0xd5/0x110 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] wait_for_key_construction+0x10b/0x140 security/keys/request_key.c:664 request_key_tag+0x7a/0xb0 security/keys/request_key.c:705 dns_query+0x257/0x6c3 net/dns_resolver/dns_query.c:128 afs_dns_query+0x122/0x390 fs/afs/addr_list.c:249 afs_update_cell fs/afs/cell.c:403 [inline] afs_manage_cell+0x8c5/0x11c0 fs/afs/cell.c:708 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 2 locks held by kworker/u4:1/21: #0: ffff8880ae735e18 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1276 [inline] #0: ffff8880ae735e18 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x230/0x1e80 kernel/sched/core.c:4115 #1: ffff8880ae720ec8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2fb/0x400 kernel/sched/psi.c:833 1 lock held by khungtaskd/1137: #0: ffffffff89bc3000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6465: #0: ffff8880a646b3f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:928 2 locks held by kworker/0:4/8038: #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880999ab938 ((wq_completion)afs){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90016e2fda8 ((work_completion)(&cell->manager)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 1 lock held by syz-executor.5/18791: #0: ffff88808be60210 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:770 [inline] #0: ffff88808be60210 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604 1 lock held by syz-executor.2/18802: #0: ffff88804d70c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff88804d70c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_setsockopt+0x401/0x2e00 net/packet/af_packet.c:3692 1 lock held by syz-executor.2/18812: #0: ffff88804d8a8120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff88804d8a8120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2f/0xc00 net/packet/af_packet.c:3098 1 lock held by syz-executor.3/18803: #0: ffff8880988a1750 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:770 [inline] #0: ffff8880988a1750 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604 1 lock held by syz-executor.1/18810: #0: ffff888050290120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff888050290120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_setsockopt+0x401/0x2e00 net/packet/af_packet.c:3692 1 lock held by syz-executor.1/18814: #0: ffff88804e6d8120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff88804e6d8120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2f/0xc00 net/packet/af_packet.c:3098 1 lock held by syz-executor.0/18813: #0: ffff8880a6c34120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff8880a6c34120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_setsockopt+0x401/0x2e00 net/packet/af_packet.c:3692 1 lock held by syz-executor.0/18817: #0: ffff88808b842120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1585 [inline] #0: ffff88808b842120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2f/0xc00 net/packet/af_packet.c:3098 1 lock held by syz-executor.4/18820: #0: ffff88808bd80c90 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:770 [inline] #0: ffff88808bd80c90 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1137 Comm: khungtaskd Not tainted 5.8.0-rc3-next-20200701-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:339 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18685 Comm: (d-rfkill) Not tainted 5.8.0-rc3-next-20200701-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:exit_to_user_mode arch/x86/entry/common.c:101 [inline] RIP: 0010:do_syscall_64+0x87/0xe0 arch/x86/entry/common.c:371 Code: 4c 40 88 48 89 45 50 48 89 ef e8 94 bf 17 f9 e8 7f e9 90 f9 48 8b 7c 24 10 e8 f5 08 71 f9 0f 1f 44 00 00 0f 00 2d e9 99 57 00 <48> 8b 7c 24 10 5b 5d e9 fd 3b 00 00 48 89 ef e8 e5 c1 17 f9 48 89 RSP: 0018:ffffc90001c17f40 EFLAGS: 00000046 RAX: 0000000000000007 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffff888058694994 RBP: ffffc90001c17f58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fd231f8f500(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faf3c0be000 CR3: 000000009ef49000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fd23082d28d Code: Bad RIP value. RSP: 002b:00007ffd3b4e4f10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: fffffffffffffff7 RBX: 000000000006afa3 RCX: 00007fd23082d28d RDX: 00007ffd3b4e4f98 RSI: 00007ffd3b4e4f90 RDI: 000000000006afa3 RBP: 0000000000100000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000293 R12: 0000000000000002 R13: 00007ffd3b4e4f90 R14: 0000000000000000 R15: 00007ffd3b4e5210