INFO: task syz-executor.1:5073 blocked for more than 143 seconds. Not tainted 5.6.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28328 5073 19508 0x80004004 Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4154 schedule_timeout+0x6db/0xba0 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x26a/0x3c0 kernel/sched/completion.c:136 io_queue_file_removal+0x1af/0x1e0 fs/io_uring.c:5840 __io_sqe_files_update.isra.0+0x3a1/0xb00 fs/io_uring.c:5881 io_sqe_files_update fs/io_uring.c:5932 [inline] __io_uring_register+0x377/0x2c00 fs/io_uring.c:7145 __do_sys_io_uring_register fs/io_uring.c:7216 [inline] __se_sys_io_uring_register fs/io_uring.c:7198 [inline] __x64_sys_io_uring_register+0x192/0x560 fs/io_uring.c:7198 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c849 Code: Bad RIP value. RSP: 002b:00007f193fdfbc78 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab RAX: ffffffffffffffda RBX: 00007f193fdfc6d4 RCX: 000000000045c849 RDX: 0000000020000100 RSI: 0000000000000006 RDI: 0000000000000003 RBP: 000000000076bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000000a R13: 00000000000001fe R14: 00000000004d2f28 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by systemd/1: 1 lock held by khungtaskd/1100: #0: ffffffff897accc0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5331 1 lock held by in:imklog/6722: #0: ffff888093a79660 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:826 1 lock held by syz-executor.1/5073: #0: ffff88809ac00320 (&ctx->uring_lock){+.+.}, at: __do_sys_io_uring_register fs/io_uring.c:7215 [inline] #0: ffff88809ac00320 (&ctx->uring_lock){+.+.}, at: __se_sys_io_uring_register fs/io_uring.c:7198 [inline] #0: ffff88809ac00320 (&ctx->uring_lock){+.+.}, at: __x64_sys_io_uring_register+0x181/0x560 fs/io_uring.c:7198 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1100 Comm: khungtaskd Not tainted 5.6.0-rc7-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 kthread+0x357/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 17566 Comm: kworker/u4:3 Not tainted 5.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_tt_purge RIP: 0010:strlen+0x4d/0x90 lib/string.c:544 Code: 07 38 d0 7f 04 84 c0 75 48 80 7d 00 00 74 39 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0 01 48 89 c2 48 89 c1 48 c1 ea 03 <83> e1 07 0f b6 14 1a 38 ca 7f 04 84 d2 75 1f 80 38 00 75 de 48 83 RSP: 0018:ffffc90003677ab8 EFLAGS: 00000802 RAX: ffffffff88d824a3 RBX: dffffc0000000000 RCX: ffffffff88d824a3 RDX: 1ffffffff11b0494 RSI: ffff8880831448f0 RDI: ffffffff88d824a0 RBP: ffffffff88d824a0 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8157d9b0 R11: ffffffff8a65d247 R12: ffffffff89793c60 R13: 0000000000000000 R14: ffff8880831448f0 R15: ffffc90003677b98 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f137d74c020 CR3: 000000009a72a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_event_get_offsets_lock_acquire include/trace/events/lock.h:13 [inline] perf_trace_lock_acquire+0xb9/0x530 include/trace/events/lock.h:13 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x2e1/0x420 kernel/locking/lockdep.c:4483 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] batadv_tt_local_purge+0x104/0x360 net/batman-adv/translation-table.c:1444 batadv_tt_purge+0x2b/0xa30 net/batman-adv/translation-table.c:3801 process_one_work+0x94b/0x1690 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 kernel/workqueue.c:2412 kthread+0x357/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352