INFO: task syz-executor255:8499 blocked for more than 143 seconds. Not tainted 5.14.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor255 state:D stack:27528 pid: 8499 ppid: 8467 flags:0x00004006 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 __lock_sock+0x13d/0x260 net/core/sock.c:2644 lock_sock_nested+0xf6/0x120 net/core/sock.c:3185 lock_sock include/net/sock.h:1612 [inline] rfcomm_sk_state_change+0xb4/0x390 net/bluetooth/rfcomm/sock.c:73 __rfcomm_dlc_close+0x1b6/0x8a0 net/bluetooth/rfcomm/core.c:489 rfcomm_dlc_close+0x1ea/0x240 net/bluetooth/rfcomm/core.c:520 __rfcomm_sock_close+0xac/0x260 net/bluetooth/rfcomm/sock.c:220 rfcomm_sock_shutdown+0xe9/0x210 net/bluetooth/rfcomm/sock.c:931 rfcomm_sock_release+0x5f/0x140 net/bluetooth/rfcomm/sock.c:951 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbd4/0x2a60 kernel/exit.c:825 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: 0033:0x445fe9 RSP: 002b:00007ffcbd932648 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 0000000000445fe9 RDX: 0000000000000080 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 0000000000000003 R08: 000000ff00000001 R09: 000000ff00000001 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000234d2b8 R13: 0000000000000072 R14: 00007ffcbd9326a0 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/1653: #0: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by krfcommd/4781: #0: ffffffff8d306528 (rfcomm_mutex){+.+.}-{3:3}, at: rfcomm_process_sessions net/bluetooth/rfcomm/core.c:1979 [inline] #0: ffffffff8d306528 (rfcomm_mutex){+.+.}-{3:3}, at: rfcomm_run+0x2ed/0x4a20 net/bluetooth/rfcomm/core.c:2086 2 locks held by in:imklog/8206: #0: ffff8880182ce5f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 #1: ffff8880b9c51a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:460 [inline] #1: ffff8880b9c51a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1307 [inline] #1: ffff8880b9c51a58 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1610 [inline] #1: ffff8880b9c51a58 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x233/0x26f0 kernel/sched/core.c:5852 4 locks held by syz-executor255/8499: #0: ffff888039a83690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #0: ffff888039a83690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:648 #1: ffff88802fa31120 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline] #1: ffff88802fa31120 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}, at: rfcomm_sock_shutdown+0x54/0x210 net/bluetooth/rfcomm/sock.c:928 #2: ffffffff8d306528 (rfcomm_mutex){+.+.}-{3:3}, at: rfcomm_dlc_close+0x34/0x240 net/bluetooth/rfcomm/core.c:507 #3: ffff888141bd6d28 (&d->lock){+.+.}-{3:3}, at: __rfcomm_dlc_close+0x162/0x8a0 net/bluetooth/rfcomm/core.c:487 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1653 Comm: khungtaskd Not tainted 5.14.0-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: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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14 Comm: rcu_preempt Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:try_to_del_timer_sync+0x2f/0x110 kernel/time/timer.c:1224 Code: 00 00 00 00 fc ff df 41 54 49 89 fc 55 53 48 83 ec 60 48 89 e3 48 c7 04 24 b3 8a b5 41 48 c7 44 24 08 fe df 13 8b 48 c1 eb 03 <48> c7 44 24 10 10 ea 64 81 4a 8d 04 2b c7 00 f1 f1 f1 f1 c7 40 04 RSP: 0018:ffffc90000d37c70 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: 1ffff920001a6f8e RCX: 0000000000000000 RDX: ffff888010e71c40 RSI: ffffffff8164ec50 RDI: ffffc90000d37d50 RBP: ffffc90000d37d18 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8164ec03 R11: 0000000000000001 R12: ffffc90000d37d50 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888010e71c40 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4cc40c0000 CR3: 000000003724f000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: del_timer_sync+0x138/0x1b0 kernel/time/timer.c:1382 schedule_timeout+0x152/0x2a0 kernel/time/timer.c:1882 rcu_gp_fqs_loop kernel/rcu/tree.c:1996 [inline] rcu_gp_kthread+0xd34/0x1980 kernel/rcu/tree.c:2169 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess), 6 bytes skipped: 0: df 41 54 filds 0x54(%rcx) 3: 49 89 fc mov %rdi,%r12 6: 55 push %rbp 7: 53 push %rbx 8: 48 83 ec 60 sub $0x60,%rsp c: 48 89 e3 mov %rsp,%rbx f: 48 c7 04 24 b3 8a b5 movq $0x41b58ab3,(%rsp) 16: 41 17: 48 c7 44 24 08 fe df movq $0xffffffff8b13dffe,0x8(%rsp) 1e: 13 8b 20: 48 c1 eb 03 shr $0x3,%rbx * 24: 48 c7 44 24 10 10 ea movq $0xffffffff8164ea10,0x10(%rsp) <-- trapping instruction 2b: 64 81 2d: 4a 8d 04 2b lea (%rbx,%r13,1),%rax 31: c7 00 f1 f1 f1 f1 movl $0xf1f1f1f1,(%rax) 37: c7 .byte 0xc7 38: 40 rex 39: 04 .byte 0x4