INFO: task syz-executor.5:9188 blocked for more than 143 seconds. Not tainted 5.17.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28456 pid: 9188 ppid: 3625 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4995 [inline] __schedule+0xa94/0x4910 kernel/sched/core.c:6304 schedule+0xd2/0x260 kernel/sched/core.c:6377 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436 __mutex_lock_common kernel/locking/mutex.c:673 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733 tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] tty_open+0x55e/0x1000 drivers/tty/tty_io.c:2133 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x1250 fs/open.c:824 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f193aaf7049 RSP: 002b:00007f193944b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f193ac0a030 RCX: 00007f193aaf7049 RDX: 0000000000000000 RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007f193ab5108d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f193b13db1f R14: 00007f193944b300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6460 2 locks held by kworker/u4:5/1406: 2 locks held by getty/3281: #0: ffff88814ab49098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002b662e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2075 3 locks held by syz-executor.5/9187: 1 lock held by syz-executor.5/9188: #0: ffffffff8c5b1d68 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2050 [inline] #0: ffffffff8c5b1d68 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x55e/0x1000 drivers/tty/tty_io.c:2133 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.17.0-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:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:369 kthread+0x2e9/0x3a0 kernel/kthread.c:377 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: 1406 Comm: kworker/u4:5 Not tainted 5.17.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_is_held_type+0xeb/0x140 kernel/locking/lockdep.c:5684 Code: 45 31 ed 44 39 f0 41 0f 94 c5 48 c7 c7 00 60 ac 89 e8 89 0d 00 00 b8 ff ff ff ff 65 0f c1 05 ac 59 b6 76 83 f8 01 75 29 9c 58 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 44 89 RSP: 0018:ffffc90005c9fb58 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffffff8bb84520 R08: 0000000000000000 R09: ffffffff8d942617 R10: fffffbfff1b284c2 R11: 0000000000000000 R12: ffff88801dc4d700 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88801dc4e188 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f21d0438c40 CR3: 0000000074924000 CR4: 00000000003506f0 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5610 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 45 31 ed xor %r13d,%r13d 3: 44 39 f0 cmp %r14d,%eax 6: 41 0f 94 c5 sete %r13b a: 48 c7 c7 00 60 ac 89 mov $0xffffffff89ac6000,%rdi 11: e8 89 0d 00 00 callq 0xd9f 16: b8 ff ff ff ff mov $0xffffffff,%eax 1b: 65 0f c1 05 ac 59 b6 xadd %eax,%gs:0x76b659ac(%rip) # 0x76b659cf 22: 76 23: 83 f8 01 cmp $0x1,%eax 26: 75 29 jne 0x51 28: 9c pushfq 29: 58 pop %rax * 2a: f6 c4 02 test $0x2,%ah <-- trapping instruction 2d: 75 3d jne 0x6c 2f: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 36: 00 37: 74 01 je 0x3a 39: fb sti 3a: 48 83 c4 08 add $0x8,%rsp 3e: 44 rex.R 3f: 89 .byte 0x89