INFO: task syz-executor.2:8856 can't die for more than 143 seconds. task:syz-executor.2 state:D stack:29752 pid: 8856 ppid: 6866 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:00007f9330e8ebf8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 000000000045d5b9 RDX: 0000000020ffe000 RSI: 0000000020000200 RDI: 00000000000016bd RBP: 000000000118cf98 R08: 00000000200000c0 R09: 00000000200000c0 R10: 0000000020000040 R11: 0000000000000206 R12: 0000000020ffe000 R13: 0000000020ffc000 R14: 00000000200000c0 R15: 0000000020000040 INFO: task syz-executor.2:8856 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.2 state:D stack:29752 pid: 8856 ppid: 6866 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:00007f9330e8ebf8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 000000000045d5b9 RDX: 0000000020ffe000 RSI: 0000000020000200 RDI: 00000000000016bd RBP: 000000000118cf98 R08: 00000000200000c0 R09: 00000000200000c0 R10: 0000000020000040 R11: 0000000000000206 R12: 0000000020ffe000 R13: 0000000020ffc000 R14: 00000000200000c0 R15: 0000000020000040 INFO: task io_uring-sq:8859 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: 8859 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: 2 locks held by kworker/u4:0/7: 3 locks held by kworker/u4:1/21: 1 lock held by khungtaskd/1174: #0: ffffffff89c67500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829 1 lock held by in:imklog/6548: #0: ffff8880989adbb0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1174 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 21 Comm: kworker/u4:1 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_iv_send_outstanding_bat_ogm_packet RIP: 0010:batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:753 [inline] RIP: 0010:batadv_iv_ogm_schedule_buff+0x590/0x1410 net/batman-adv/bat_iv_ogm.c:826 Code: 48 c1 e8 03 4c 01 e8 48 89 44 24 18 48 8b 44 24 48 48 c1 e8 03 4c 01 e8 48 89 44 24 20 e8 08 b1 9b f9 48 8b 44 24 18 80 38 00 <0f> 85 a1 0d 00 00 48 8b 74 24 10 8b 44 24 08 48 8b 16 48 8d 1c c2 RSP: 0018:ffffc90000dd7b98 EFLAGS: 00000246 RAX: ffffed10137c9718 RBX: 0000000000000400 RCX: ffffffff87d93446 RDX: ffff8880a97f0580 RSI: ffffffff87d931f8 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8880a97f0e88 R10: 00000000000000fd R11: 000000000000016e R12: ffff88809703909c R13: dffffc0000000000 R14: ffff888051480c00 R15: 00000000000000fd FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f242ca36000 CR3: 00000000a2eb5000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:870 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:863 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x5c8/0x800 net/batman-adv/bat_iv_ogm.c:1724 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