INFO: task syz.1.750:11356 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.750 state:D stack:28968 pid:11356 tgid:11351 ppid:5598 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 __wait_on_freeing_inode+0x214/0x3b0 fs/inode.c:2619 find_inode+0x3ca/0x710 fs/inode.c:1051 inode_insert5+0x12e/0x5d0 fs/inode.c:1313 insert_inode_locked4+0x74/0xc0 fs/inode.c:1948 nilfs_insert_inode_locked fs/nilfs2/inode.c:297 [inline] nilfs_new_inode+0x4e6/0x810 fs/nilfs2/inode.c:351 nilfs_mkdir+0x121/0x390 fs/nilfs2/namei.c:234 vfs_mkdir+0x402/0x620 fs/namei.c:5276 filename_mkdirat+0x289/0x520 fs/namei.c:5309 __do_sys_mkdirat fs/namei.c:5330 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f949000cd07 RSP: 002b:00007f948e223e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f948e223ee0 RCX: 00007f949000cd07 RDX: 00000000000001ff RSI: 0000200000000080 RDI: 00000000ffffff9c RBP: 0000200000000440 R08: 0000200000000080 R09: 0000000000000000 R10: 0000200000000440 R11: 0000000000000246 R12: 0000200000000080 R13: 00007f948e223ea0 R14: 0000000000000000 R15: 0000000000000000 INFO: task segctord:11353 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:segctord state:D stack:25000 pid:11353 tgid:11353 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607 rwbase_write_lock+0x3cf/0x720 kernel/locking/rwbase_rt.c:279 nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2591 [inline] nilfs_segctor_thread+0x6be/0xdb0 fs/nilfs2/segment.c:2706 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/1:1/36: #0: ffff88813ff1f938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff1f938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90000ab7c40 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90000ab7c40 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff8880222ae7f0 (sb_internal#6){.+.+}-{0:0}, at: nilfs_evict_inode+0x156/0x480 fs/nilfs2/inode.c:868 1 lock held by khungtaskd/38: #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 6 locks held by kworker/u8:13/1679: 5 locks held by kworker/u8:16/3354: 2 locks held by getty/5351: #0: ffff8880286080a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 4 locks held by syz.1.750/11356: #0: ffff8880222ae500 (sb_writers#31){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888068742ae0 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff888068742ae0 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff888068742ae0 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff888068742ae0 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 #2: ffff8880222ae7f0 (sb_internal#6){.+.+}-{0:0}, at: nilfs_mkdir+0xd6/0x390 fs/nilfs2/namei.c:228 #3: ffff88802e7862b0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_begin+0x364/0x710 fs/nilfs2/segment.c:221 1 lock held by segctord/11353: #0: ffff88802e7862b0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357 5 locks held by syz.3.947/13400: 3 locks held by syz.2.950/13405: 1 lock held by syz.9.951/13407: 1 lock held by udevadm/13423: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11487 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline] RIP: 0010:__lock_acquire+0x18fa/0x2ce0 kernel/locking/lockdep.c:5237 Code: 14 25 ff 0f 00 00 39 05 d0 75 04 12 73 06 89 05 c8 75 04 12 48 8b 02 48 89 df 4c 39 e8 0f 84 34 fe ff ff 4c 89 78 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 20 fe ff ff 48 89 fb 48 c7 c7 f0 02 09 RSP: 0018:ffffc9000609f6a0 EFLAGS: 00000002 RAX: ffffffff9648d828 RBX: 00000000000003cc RCX: 0000000000000060 RDX: ffffffff9638f4b8 RSI: ffff8880362bca80 RDI: 00000000000003cc RBP: df968179fa095c93 R08: ffffc9000609f668 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a13580 R12: 000000000000005f R13: ffffffff934cb508 R14: ffff8880362bbe00 R15: ffffffff963a2618 FS: 0000555589048500(0000) GS:ffff888125d46000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a90ef315f8 CR3: 000000005d7b4000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 rt_mutex_slowunlock+0xbf/0xa20 kernel/locking/rtmutex.c:1430 rt_spin_unlock+0x10d/0x200 kernel/locking/spinlock_rt.c:84 spin_unlock include/linux/spinlock_rt.h:109 [inline] d_walk+0x15c/0x6e0 fs/dcache.c:1491 shrink_dcache_tree+0x1a8/0x410 fs/dcache.c:1721 do_one_tree+0x18/0xa0 fs/dcache.c:1795 shrink_dcache_for_umount+0x111/0x510 fs/dcache.c:1812 generic_shutdown_super+0x6f/0x2d0 fs/super.c:625 kill_block_super+0x44/0x90 fs/super.c:1665 hfs_kill_super+0x41/0x50 fs/hfs/super.c:441 deactivate_locked_super+0xbc/0x130 fs/super.c:477 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbe0119f0d7 Code: a2 c7 05 1c 26 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fffe4e86a68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fbe0123330a RCX: 00007fbe0119f0d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffe4e86b20 RBP: 00007fffe4e86b20 R08: 00007fffe4e87b20 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffe4e87bb0 R13: 00007fbe0123330a R14: 00000000000bc086 R15: 00007fffe4e87bf0