INFO: task syz.1.1047:10192 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1047 state:D stack:28464 pid:10192 ppid:4272 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 rwsem_down_read_slowpath+0x4f4/0x840 kernel/locking/rwsem.c:1094 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x94/0x2d0 kernel/locking/rwsem.c:1522 inode_lock_shared include/linux/fs.h:768 [inline] lookup_slow+0x46/0x70 fs/namei.c:1714 walk_component+0x2be/0x3f0 fs/namei.c:2006 lookup_last fs/namei.c:2463 [inline] path_lookupat+0x169/0x440 fs/namei.c:2487 filename_lookup+0x1f0/0x500 fs/namei.c:2516 user_path_at_empty+0x3e/0x60 fs/namei.c:2913 user_path_at include/linux/namei.h:57 [inline] inotify_find_inode fs/notify/inotify/inotify_user.c:378 [inline] __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:777 [inline] __se_sys_inotify_add_watch+0x18e/0x1020 fs/notify/inotify/inotify_user.c:730 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa15f78f749 RSP: 002b:00007fa1606ba038 EFLAGS: 00000246 ORIG_RAX: 00000000000000fe RAX: ffffffffffffffda RBX: 00007fa15f9e6090 RCX: 00007fa15f78f749 RDX: 000000004000064f RSI: 00002000000001c0 RDI: 0000000000000008 RBP: 00007fa15f813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa15f9e6128 R14: 00007fa15f9e6090 R15: 00007ffd76f07318 INFO: task syz.1.1047:10194 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1047 state:D stack:27856 pid:10194 ppid:4272 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 rwsem_down_write_slowpath+0xbed/0x1090 kernel/locking/rwsem.c:1189 inode_lock include/linux/fs.h:758 [inline] open_last_lookups fs/namei.c:3555 [inline] path_openat+0x7c2/0x2e70 fs/namei.c:3788 do_filp_open+0x1c1/0x3c0 fs/namei.c:3818 do_sys_openat2+0x142/0x490 fs/open.c:1320 __do_sys_openat2 fs/open.c:1379 [inline] __se_sys_openat2+0x224/0x2c0 fs/open.c:1355 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa15f78f749 RSP: 002b:00007fa160699038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b5 RAX: ffffffffffffffda RBX: 00007fa15f9e6180 RCX: 00007fa15f78f749 RDX: 0000200000000100 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007fa15f813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000018 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa15f9e6218 R14: 00007fa15f9e6180 R15: 00007ffd76f07318 Showing all locks held in the system: 6 locks held by kworker/u4:1/11: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c92bab0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c92c2d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 3 locks held by kworker/u4:3/46: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90000b77d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 2 locks held by getty/4028: #0: ffff888030082098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 3 locks held by kworker/1:6/4341: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc9000496fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/0:8/5317: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90003247d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 2 locks held by syz.1.1047/10177: 1 lock held by syz.1.1047/10192: #0: ffff888055b9dfa0 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline] #0: ffff888055b9dfa0 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1714 2 locks held by syz.1.1047/10194: #0: ffff8880741f4460 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402 #1: ffff888055b9dfa0 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff888055b9dfa0 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: open_last_lookups fs/namei.c:3555 [inline] #1: ffff888055b9dfa0 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x7c2/0x2e70 fs/namei.c:3788 3 locks held by kworker/u4:18/10900: 1 lock held by syz-executor/12168: #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147 1 lock held by syz.6.1557/12227: #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741