INFO: task syz.1.690:7652 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.690 state:D stack:26656 pid:7652 tgid:7651 ppid:5837 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121 __mutex_lock_common kernel/locking/mutex.c:710 [inline] __mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794 nfsd_nl_threads_set_doit+0x2bb/0xde0 fs/nfsd/nfsctl.c:1633 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:786 [inline] __sock_sendmsg net/socket.c:801 [inline] ____sys_sendmsg+0x972/0x9f0 net/socket.c:2650 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2704 __sys_sendmsg net/socket.c:2736 [inline] __do_sys_sendmsg net/socket.c:2741 [inline] __se_sys_sendmsg net/socket.c:2739 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff61699c819 RSP: 002b:00007ff6177d7028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff616c15fa0 RCX: 00007ff61699c819 RDX: 0000000004000080 RSI: 0000200000000100 RDI: 0000000000000003 RBP: 00007ff6177d7090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ff616c16038 R14: 00007ff616c15fa0 R15: 00007ffe41099e48 INFO: task syz.0.717:7728 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.717 state:D stack:25560 pid:7728 tgid:7728 ppid:5836 task_flags:0x400040 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 request_wait_answer fs/fuse/dev.c:590 [inline] __fuse_request_send fs/fuse/dev.c:604 [inline] __fuse_simple_request+0x12b7/0x1db0 fs/fuse/dev.c:699 fuse_simple_request fs/fuse/fuse_i.h:1264 [inline] fuse_flush+0x66a/0x8a0 fs/fuse/file.c:500 filp_flush+0xbd/0x190 fs/open.c:1469 filp_close+0x1d/0x40 fs/open.c:1482 __range_close fs/file.c:794 [inline] __do_sys_close_range fs/file.c:855 [inline] __se_sys_close_range+0x3d4/0x900 fs/file.c:819 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faf32f9c819 RSP: 002b:00007ffe7ce75488 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007faf33217da0 RCX: 00007faf32f9c819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007faf33217da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007faf33217cb0 R11: 0000000000000246 R12: 000000000002b8d5 R13: 00007faf3321609c R14: 000000000002b638 R15: 00007faf33216090 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb5d0a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5d0a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5d0a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5595: #0: ffff8880375010a0 (&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+0x45c/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz.3.681/7629: #0: ffffffff90068508 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ee87980 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2bb/0xde0 fs/nfsd/nfsctl.c:1633 2 locks held by syz.1.690/7652: #0: ffffffff90068508 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ee87980 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2bb/0xde0 fs/nfsd/nfsctl.c:1633 6 locks held by kworker/0:6/7809: #0: ffff88801f689940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff88801f689940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90003b67c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90003b67c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffff88802b41f1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #2: ffff88802b41f1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88802b41c560 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff88802b41c560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff88802b41c560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff88802b41c560 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff88802b41c560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802af48c60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802af48c60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802af48c60 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802af48c60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 #5: ffffffff8f89bac8 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x14e/0x1840 drivers/usb/core/hub.c:3067 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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: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+0xfd3/0x1030 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: 5823 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:kasan_check_range+0x1c8/0x2c0 mm/kasan/generic.c:200 Code: 49 01 dc 4d 01 f3 49 8d 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 0e 41 80 3b 00 75 7c 49 ff c3 49 ff cc 75 f2 5b <41> 5c 41 5d 41 5e 41 5f 5d e9 1a 24 91 09 cc 45 84 ff 0f 85 a1 00 RSP: 0018:ffffc90003ad7710 EFLAGS: 00000097 RAX: 00000000ffffff01 RBX: ffffffff9a9ebef8 RCX: ffffffff81a320db RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90003ad7780 RBP: ffffc90003ad77f8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200075aef0 R12: fffff5200075aef0 R13: ffffffff9a9ebf00 R14: fffff5200075aef1 R15: 1ffff9200075aef0 FS: 0000555578df0540(0000) GS:ffff888124fe5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005628fa7a5f50 CR3: 00000000757e0000 CR4: 00000000003526f0 Call Trace: instrument_read_write include/linux/instrumented.h:55 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x12b/0x2f0 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock_irqsave+0x4c/0x60 kernel/locking/spinlock.c:166 debug_object_activate+0x83/0x580 lib/debugobjects.c:835 debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline] debug_activate kernel/time/hrtimer.c:528 [inline] remove_and_enqueue_same_base kernel/time/hrtimer.c:1259 [inline] __hrtimer_start_range_ns kernel/time/hrtimer.c:1396 [inline] hrtimer_start_range_ns+0x579/0xed0 kernel/time/hrtimer.c:1491 hrtimer_start include/linux/hrtimer.h:220 [inline] hrtick_cond_restart kernel/sched/core.c:919 [inline] hrtick_schedule_exit kernel/sched/core.c:981 [inline] finish_lock_switch kernel/sched/core.c:5090 [inline] finish_task_switch+0x3cd/0xbe0 kernel/sched/core.c:5209 context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1664/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 do_nanosleep+0x1c2/0x620 kernel/time/hrtimer.c:2292 hrtimer_nanosleep+0x18f/0x3a0 kernel/time/hrtimer.c:2338 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline] __se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f19bdb57997 Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffde513f3b0 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000555578df0540 RCX: 00007f19bdb57997 RDX: 00007ffde513f3f0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffde513f8d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004 R13: 00007ffde513f42c R14: 00007ffde513f4c0 R15: 0000000000000000