INFO: task syz-executor.5:10534 blocked for more than 143 seconds. Not tainted 5.14.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28488 pid:10534 ppid: 9164 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4681 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5938 schedule+0xd3/0x270 kernel/sched/core.c:6017 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6076 __mutex_lock_common kernel/locking/mutex.c:1036 [inline] __mutex_lock+0x7b6/0x10a0 kernel/locking/mutex.c:1104 io_uring_del_tctx_node+0x105/0x350 fs/io_uring.c:9103 io_uring_clean_tctx fs/io_uring.c:9119 [inline] io_uring_cancel_generic+0x6c0/0x890 fs/io_uring.c:9202 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x28b/0x2a60 kernel/exit.c:780 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2808 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fbcafa34218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 000000000056c040 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c040 RBP: 000000000056c038 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c044 R13: 0000000000a9fb1f R14: 00007fbcafa34300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1656: #0: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/8153: #0: ffff888033f554f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 1 lock held by syz-executor.5/10534: #0: ffff88807911c0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_del_tctx_node+0x105/0x350 fs/io_uring.c:9103 3 locks held by syz-executor.5/10559: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1656 Comm: khungtaskd Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xd0a/0xfc0 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 121 Comm: kworker/u4:3 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:mark_usage kernel/locking/lockdep.c:4514 [inline] RIP: 0010:__lock_acquire+0x897/0x54a0 kernel/locking/lockdep.c:4969 Code: 03 0f 8e 09 49 00 00 41 8b b5 d0 09 00 00 85 f6 74 18 ba 06 00 00 00 4c 89 e6 4c 89 ef e8 e1 da ff ff 85 c0 0f 84 8f 05 00 00 08 00 00 00 4c 89 e6 4c 89 ef e8 c9 da ff ff 85 c0 0f 84 77 05 RSP: 0018:ffffc9000131fa68 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 00000000000006a6 RCX: ffffffff815ac80d RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fd25a38 RBP: 0000000000000004 R08: 0000000000000000 R09: ffffffff8fcd59b7 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880143cdf00 R13: ffff8880143cd4c0 R14: ffff8880143cdeb0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6880b65ce8 CR3: 000000008803d000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 rcu_lock_acquire include/linux/rcupdate.h:267 [inline] rcu_read_lock include/linux/rcupdate.h:687 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:404 [inline] batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:715 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 03 0f add (%rdi),%ecx 2: 8e 09 mov (%rcx),%cs 4: 49 00 00 rex.WB add %al,(%r8) 7: 41 8b b5 d0 09 00 00 mov 0x9d0(%r13),%esi e: 85 f6 test %esi,%esi 10: 74 18 je 0x2a 12: ba 06 00 00 00 mov $0x6,%edx 17: 4c 89 e6 mov %r12,%rsi 1a: 4c 89 ef mov %r13,%rdi 1d: e8 e1 da ff ff callq 0xffffdb03 22: 85 c0 test %eax,%eax 24: 0f 84 8f 05 00 00 je 0x5b9 2a: ba 08 00 00 00 mov $0x8,%edx <-- trapping instruction 2f: 4c 89 e6 mov %r12,%rsi 32: 4c 89 ef mov %r13,%rdi 35: e8 c9 da ff ff callq 0xffffdb03 3a: 85 c0 test %eax,%eax 3c: 0f .byte 0xf 3d: 84 77 05 test %dh,0x5(%rdi)