INFO: task kworker/0:11:5263 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/0:11 D27808 5263 2 0x80004000 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 kworker/0:11/5263: #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888214ccc938 ((wq_completion)afs){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc900157a7da8 ((work_completion)(&cell->manager)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1149 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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60