INFO: task syz.0.506:10204 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.506 state:D stack:28128 pid:10204 tgid:10202 ppid:8718 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1072 [inline] __start_dirop fs/namei.c:2873 [inline] start_dirop fs/namei.c:2884 [inline] filename_create+0x1fb/0x360 fs/namei.c:4888 do_symlinkat+0x120/0x3d0 fs/namei.c:5543 __do_sys_symlinkat fs/namei.c:5571 [inline] __se_sys_symlinkat fs/namei.c:5568 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5568 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe597d7f749 RSP: 002b:00007fe595fbd038 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 00007fe597fd6090 RCX: 00007fe597d7f749 RDX: 0000200000000ec0 RSI: 0000000000000006 RDI: 0000200000000dc0 RBP: 00007fe597e03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe597fd6128 R14: 00007fe597fd6090 R15: 00007ffd6d885e48 INFO: task syz.0.506:10205 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.506 state:D stack:28128 pid:10205 tgid:10202 ppid:8718 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1072 [inline] __start_dirop fs/namei.c:2873 [inline] start_dirop fs/namei.c:2884 [inline] filename_create+0x1fb/0x360 fs/namei.c:4888 do_symlinkat+0x120/0x3d0 fs/namei.c:5543 __do_sys_symlinkat fs/namei.c:5571 [inline] __se_sys_symlinkat fs/namei.c:5568 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5568 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe597d7f749 RSP: 002b:00007fe595f9c038 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 00007fe597fd6180 RCX: 00007fe597d7f749 RDX: 00002000000004c0 RSI: 0000000000000006 RDI: 0000200000000040 RBP: 00007fe597e03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe597fd6218 R14: 00007fe597fd6180 R15: 00007ffd6d885e48 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by udevd/5169: 1 lock held by crond/5542: 2 locks held by getty/5554: #0: ffff88814e4d50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:18/6113: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc90005fdfbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90005fdfbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 5 locks held by kworker/u8:23/7401: 4 locks held by kworker/u8:30/7408: #0: ffff88801dab2138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801dab2138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000567fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000567fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffff8880308fe0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff888041796d28 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 2 locks held by kworker/u8:32/7410: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000565fbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000565fbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 4 locks held by syz.0.506/10203: 2 locks held by syz.0.506/10204: #0: ffff8880308fe480 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499 #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x1fb/0x360 fs/namei.c:4888 2 locks held by syz.0.506/10205: #0: ffff8880308fe480 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499 #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline] #1: ffff8880417970f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x1fb/0x360 fs/namei.c:4888 1 lock held by syz.8.709/11787: 1 lock held by dhcpcd-run-hook/11789: 4 locks held by syz.7.711/11793: ============================================= 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 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 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] __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:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11787 Comm: syz.8.709 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0033:0x7f800fb409d8 Code: 9e fd ff ff 41 8d 34 04 49 8b 47 10 48 39 f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 <48> 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 47 0f b6 0c 08 45 84 c9 RSP: 002b:00007f800dee54a0 EFLAGS: 00000202 RAX: 0000000000e9f27f RBX: 00007f800dee5540 RCX: 00000000000000ea RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f800dee55e0 RBP: 0000000000000102 R08: 00007f8005ac6000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007f800dee5550 R12: 0000000000000001 R13: 00007f800fd1fc40 R14: 0000000000000000 R15: 00007f800dee55e0 FS: 00007f800dee66c0 GS: 0000000000000000