INFO: task syz-executor.1:8728 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:28832 pid: 8728 ppid: 6853 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4526 schedule+0xd0/0x2a0 kernel/sched/core.c:4601 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x163/0x260 kernel/sched/completion.c:138 io_sq_thread_stop fs/io_uring.c:6906 [inline] io_finish_async fs/io_uring.c:6920 [inline] io_sq_offload_create fs/io_uring.c:7595 [inline] io_uring_create fs/io_uring.c:8671 [inline] io_uring_setup+0x1495/0x29a0 fs/io_uring.c:8744 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007fcfdc109bf8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 0000000020000100 RCX: 000000000045d5b9 RDX: 0000000020eea000 RSI: 0000000020000100 RDI: 0000000000004d85 RBP: 000000000118cf98 R08: 0000000020000440 R09: 0000000020000440 R10: 0000000020000400 R11: 0000000000000206 R12: 0000000020eea000 R13: 0000000020ee9000 R14: 0000000020000440 R15: 0000000020000400 INFO: task io_uring-sq:8730 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:io_uring-sq state:D stack:31120 pid: 8730 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4526 schedule+0xd0/0x2a0 kernel/sched/core.c:4601 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4660 kthread+0x2ac/0x4a0 kernel/kthread.c:285 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 1 lock held by khungtaskd/1166: #0: ffffffff89c67500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829 1 lock held by systemd-journal/3899: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1166 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200903-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+0x198/0x1fd lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 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: 2886 Comm: kworker/u4:5 Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_mcast_mla_update RIP: 0010:batadv_mcast_mla_rtr_flags_softif_get_ipv4 net/batman-adv/multicast.c:116 [inline] RIP: 0010:batadv_mcast_mla_rtr_flags_softif_get net/batman-adv/multicast.c:174 [inline] RIP: 0010:batadv_mcast_mla_rtr_flags_get net/batman-adv/multicast.c:264 [inline] RIP: 0010:batadv_mcast_mla_flags_get net/batman-adv/multicast.c:289 [inline] RIP: 0010:__batadv_mcast_mla_update net/batman-adv/multicast.c:909 [inline] RIP: 0010:batadv_mcast_mla_update+0x245/0x2b80 net/batman-adv/multicast.c:948 Code: 85 34 29 00 00 4d 8b a4 24 98 05 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 28 04 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 ff 28 00 00 4d 8b a4 24 28 04 00 00 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc90001d47b98 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff8880584c4000 RCX: ffffffff87dcc53c RDX: 1ffff1100b18408d RSI: ffffffff87dca84e RDI: ffff888058c20468 RBP: ffff88809f344c00 R08: 0000000000000001 R09: ffffffff8c6ab9a7 R10: 0000000000000000 R11: ffffffff87dca774 R12: ffff888058c20040 R13: ffff8880584c55c0 R14: ffff8880584c55b0 R15: ffff8880aa071800 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2b1ac98000 CR3: 0000000097a86000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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