INFO: task syz.0.65:6102 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.65 state:D stack:24680 pid:6102 tgid:6101 ppid:5709 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 __wait_on_freeing_inode+0x1a2/0x2f0 fs/inode.c:2494 find_inode+0x28c/0x450 fs/inode.c:1029 inode_insert5+0x114/0x4f0 fs/inode.c:1286 insert_inode_locked4+0x71/0xc0 fs/inode.c:1847 nilfs_insert_inode_locked fs/nilfs2/inode.c:297 [inline] nilfs_new_inode+0x4b6/0x750 fs/nilfs2/inode.c:351 nilfs_mkdir+0x109/0x330 fs/nilfs2/namei.c:234 vfs_mkdir+0x306/0x510 fs/namei.c:4453 do_mkdirat+0x247/0x590 fs/namei.c:4486 __do_sys_mkdirat fs/namei.c:4503 [inline] __se_sys_mkdirat fs/namei.c:4501 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6bc398ebe9 RSP: 002b:00007f6bc4748038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f6bc3bb5fa0 RCX: 00007f6bc398ebe9 RDX: 00000000000001c0 RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007f6bc3a11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6bc3bb6038 R14: 00007f6bc3bb5fa0 R15: 00007ffd58ea23b8 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u4:6/1041: 2 locks held by getty/5106: #0: ffff88803e80c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900028e62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:8/5969: #0: ffff88801a067548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801a067548 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000d5dfba0 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000d5dfba0 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888035e02610 (sb_internal#2){.+.+}-{0:0}, at: nilfs_evict_inode+0x15e/0x4a0 fs/nilfs2/inode.c:868 4 locks held by syz.0.65/6102: #0: ffff888035e02420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508 #1: ffff888040b52880 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline] #1: ffff888040b52880 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226 #2: ffff888035e02610 (sb_internal#2){.+.+}-{0:0}, at: nilfs_mkdir+0xcc/0x330 fs/nilfs2/namei.c:228 #3: ffff8880595ac2a0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_begin+0x365/0x710 fs/nilfs2/segment.c:221 1 lock held by segctord/6113: #0: ffff8880595ac2a0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357 2 locks held by dhcpcd/11319: #0: ffff88804191ea48 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #0: ffff88804191ea48 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff88804191ea48 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957 3 locks held by syz.5.2622/11351: 2 locks held by dhcpcd/11350: #0: ffff888040d08260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline] #0: ffff888040d08260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3197 #1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 1 lock held by dhcpcd/11352: #0: ffff888059ece260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline] #0: ffff888059ece260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3197 1 lock held by dhcpcd/11355: #0: ffff88803837a260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline] #0: ffff88803837a260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3197 1 lock held by dhcpcd/11358: #0: ffff888050d32260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline] #0: ffff888050d32260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3197 2 locks held by syz.4.2625/11360: 2 locks held by syz.3.2626/11364: 2 locks held by syz.2.2627/11363: 2 locks held by syz.5.2628/11366: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 26 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245