INFO: task syz.3.10357:29543 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.10357 state:D stack:27272 pid:29543 tgid:29541 ppid:5852 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 nfsd_nl_version_get_doit+0x16e/0xb60 fs/nfsd/nfsctl.c:1844 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2617 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2671 __sys_sendmsg net/socket.c:2703 [inline] __do_sys_sendmsg net/socket.c:2708 [inline] __se_sys_sendmsg net/socket.c:2706 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2706 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fabf378eec9 RSP: 002b:00007fabf456e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fabf39e5fa0 RCX: 00007fabf378eec9 RDX: 0000000000008800 RSI: 00002000000001c0 RDI: 0000000000000003 RBP: 00007fabf3811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fabf39e6038 R14: 00007fabf39e5fa0 R15: 00007ffdd3800bc8 Showing all locks held in the system: 6 locks held by kworker/1:0/24: #0: ffff88801da8e548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801da8e548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888027cc5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #2: ffff888027cc5198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888030d10198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff888030d10198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950 drivers/usb/core/hub.c:2335 #4: ffff88807d0de160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88807d0de160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline] #4: ffff88807d0de160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1294 #5: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:228 [inline] #5: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: input_disconnect_device drivers/input/input.c:702 [inline] #5: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: __input_unregister_device+0x31/0x640 drivers/input/input.c:2219 1 lock held by khungtaskd/31: #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by acpid/5190: #0: ffff88805e980160 (&joydev->mutex){+.+.}-{4:4}, at: joydev_open_device drivers/input/joydev.c:200 [inline] #0: ffff88805e980160 (&joydev->mutex){+.+.}-{4:4}, at: joydev_open+0x21b/0x910 drivers/input/joydev.c:272 #1: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:230 [inline] #1: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: input_open_device+0x53/0x390 drivers/input/input.c:582 2 locks held by getty/5591: #0: ffff88803005e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by udevd/6459: #0: ffff8880296b1118 (&evdev->mutex){+.+.}-{4:4}, at: evdev_open_device drivers/input/evdev.c:384 [inline] #0: ffff8880296b1118 (&evdev->mutex){+.+.}-{4:4}, at: evdev_open+0x2cf/0x5a0 drivers/input/evdev.c:478 #1: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:230 [inline] #1: ffff8880296b72c0 (&dev->mutex#2){+.+.}-{4:4}, at: input_open_device+0x53/0x390 drivers/input/input.c:582 #2: ffffffff8dd40738 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8dd40738 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 2 locks held by syz.2.9894/28502: #0: ffffffff8f131ef0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e01ddc8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919 1 lock held by syz-executor/29032: #0: ffff8880b8839fd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 2 locks held by syz.3.10357/29543: #0: ffffffff8f131ef0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e01ddc8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x16e/0xb60 fs/nfsd/nfsctl.c:1844 1 lock held by dhcpcd-run-hook/2044: 4 locks held by dhcpcd-run-hook/2051: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 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: 2052 Comm: sed Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:63 Code: a6 b6 fc f5 eb a7 e8 8f e4 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 89 fe 48 c7 c7 e0 6f 9e 8b e9 bd fe ff ff cc cc cc RSP: 0018:ffffc90003e6f670 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0c788d83ea879a00 RDX: 0000000000000001 RSI: ffff88803777c6f0 RDI: ffffffff8d716a1e RBP: ffffffff81722195 R08: 0000000000000000 R09: ffffffff81722195 R10: dffffc0000000000 R11: ffffffff81aaa470 R12: 0000000000000002 R13: ffffffff8dd3aca0 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff88812647e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd54ec7d368 CR3: 0000000078dfd000 CR4: 0000000000350ef0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5870 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4797 file_free fs/file_table.c:71 [inline] __fput+0x6c2/0xa70 fs/file_table.c:481 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 __do_sys_exit_group kernel/exit.c:1113 [inline] __se_sys_exit_group kernel/exit.c:1111 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1b63b136c5 Code: Unable to access opcode bytes at 0x7f1b63b1369b. RSP: 002b:00007ffd5e0281d8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f1b63c14fe8 RCX: 00007f1b63b136c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1b63c13680 R15: 00007f1b63c15000