INFO: task syz.0.1493:11824 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1493 state:D stack:26320 pid:11824 tgid:11819 ppid:5623 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 rwsem_down_read_slowpath+0x6ba/0x920 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x9c/0x330 kernel/locking/rwsem.c:1576 nilfs_transaction_begin+0x364/0x710 fs/nilfs2/segment.c:221 nilfs_mkdir+0xd6/0x390 fs/nilfs2/namei.c:228 vfs_mkdir+0x406/0x620 fs/namei.c:5276 filename_mkdirat+0x285/0x510 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: 0033:0x7f45a339de59 RSP: 002b:00007f45a432f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f45a3626090 RCX: 00007f45a339de59 RDX: 00000000000001c0 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f45a3433e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f45a3626128 R14: 00007f45a3626090 R15: 00007ffd52635058 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: #0: ffff8880b863b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb2/0x160 kernel/sched/core.c:675 1 lock held by khungtaskd/31: #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5373: #0: ffff8880346b70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 3 locks held by kworker/u9:8/5642: #0: ffff88806832e140 ((wq_completion)hci7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88806832e140 ((wq_completion)hci7){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90003e57c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90003e57c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff8880787e4ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1cb/0x3f0 net/bluetooth/hci_sync.c:331 2 locks held by kworker/0:6/5766: #0: ffff8880b863b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb2/0x160 kernel/sched/core.c:675 #1: ffff8880b8624440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933 7 locks held by syz.0.1493/11820: 4 locks held by syz.0.1493/11824: #0: ffff88807c8a4450 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff8880522675c0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff8880522675c0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff8880522675c0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff8880522675c0 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 #2: ffff88807c8a4640 (sb_internal#4){.+.+}-{0:0}, at: nilfs_mkdir+0xd6/0x390 fs/nilfs2/namei.c:228 #3: ffff88805102b288 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_begin+0x364/0x710 fs/nilfs2/segment.c:221 3 locks held by kworker/u9:0/11928: #0: ffff88807efb8940 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88807efb8940 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000208fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000208fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff88802652cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1cb/0x3f0 net/bluetooth/hci_sync.c:331 3 locks held by syz.0.1668/13177: 2 locks held by syz.6.1704/13358: 2 locks held by syz.6.1722/13442: 1 lock held by rm/13474: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 5c 80 02 e9 fe ff 40 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 2a 1a 00 fb f4 d7 ff 40 f5 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e807de0 EFLAGS: 00000246 RAX: 0000000000c935f5 RBX: ffffffff819ab33c RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8e22b72d RDI: ffffffff8c4bd980 RBP: ffffffff8e807eb8 R08: ffff8880b86338db R09: 1ffff110170c671b R10: dffffc0000000000 R11: ffffed10170c671c R12: 0000000000000000 R13: 1ffffffff1d11de8 R14: 1ffffffff1d00fc4 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124f56000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000560eb1e03950 CR3: 000000000e946000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:767 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:768 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x1cc/0x540 kernel/sched/idle.c:355 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454 rest_init+0x2de/0x300 init/main.c:717 start_kernel+0x392/0x3e0 init/main.c:1175 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x157