INFO: task kworker/1:5:10550 blocked for more than 147 seconds.
      Not tainted 5.8.0-rc3-next-20200629-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:5     D22920 10550      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:
1 lock held by khungtaskd/1149:
 #0: ffffffff89bc3000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779
2 locks held by agetty/6480:
 #0: ffff8880a660e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267
 #1: ffffc900010f42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156
2 locks held by kworker/1:5/10550:
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888214e50538 ((wq_completion)afs){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
 #1: ffffc90008727da8 ((work_completion)(&cell->manager)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1149 Comm: khungtaskd Not tainted 5.8.0-rc3-next-20200629-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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3867 Comm: systemd-journal Not tainted 5.8.0-rc3-next-20200629-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:PTR_ERR include/linux/err.h:31 [inline]
RIP: 0010:do_mkdirat+0x28c/0x2d0 fs/namei.c:3664
Code: 89 c3 e9 f5 fe ff ff e8 02 64 b1 ff e8 2d 06 0a 00 f7 d0 66 21 44 24 0a e9 b1 fe ff ff c7 44 24 0c 01 00 00 00 e9 ef fd ff ff <e8> df 63 b1 ff 49 89 ec e9 34 ff ff ff e8 42 f0 f0 ff e9 3c fe ff
RSP: 0018:ffffc90001277e90 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000053 RCX: ffffffff81c283a2
RDX: fffffffffffffffe RSI: ffff8880938fa100 RDI: 0000000000000007
RBP: fffffffffffffffe R08: 0000000000000000 R09: 0000000000000000
R10: fffffffffffff000 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000002 R14: 0000000000000000 R15: 00000000ffffff9c
FS:  00007fa0e91a18c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0e666e028 CR3: 0000000093a15000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fa0e845d687
Code: Bad RIP value.
RSP: 002b:00007ffe00b19628 EFLAGS: 00000293 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007ffe00b1c690 RCX: 00007fa0e845d687
RDX: 0000000000000000 RSI: 00000000000001ed RDI: 0000560379d188a0
RBP: 00007ffe00b19660 R08: 0000560379b3c3e5 R09: 0000000000000018
R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000001 R14: 0000560379d188a0 R15: 00007ffe00b19ca0