INFO: task syz.7.2984:20341 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.7.2984 state:D stack:25808 pid:20341 tgid:20337 ppid:19191 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 mmap_read_lock include/linux/mmap_lock.h:592 [inline] __mm_populate+0x182/0x390 mm/gup.c:1942 mm_populate include/linux/mm.h:3945 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:605 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7fae19c799 RSP: 002b:00007f7faf0bc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f7fae416180 RCX: 00007f7fae19c799 RDX: 000000000000000c RSI: 0000000000002000 RDI: 0000200000535000 RBP: 00007f7fae232c99 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7fae416218 R14: 00007f7fae416180 R15: 00007ffcdb209878 Showing all locks held in the system: 4 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/30: #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:3/48: #0: ffff88813fe44140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3260 #1: ffffc90000b87c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3261 #2: ffffffff8fff55c0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 1 lock held by klogd/5200: #0: ffff8880b843ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 2 locks held by getty/5604: #0: ffff8880335a50a0 (&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/0x13c0 drivers/tty/n_tty.c:2211 5 locks held by kworker/0:4/12788: #0: ffff88801faacd40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3260 #1: ffffc9000d41fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3261 #2: ffff88802a3eb1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #2: ffff88802a3eb1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88802a3e8560 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff88802a3e8560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff88802a3e8560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff88802a3e8560 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff88802a3e8560 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802967cf60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802967cf60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802967cf60 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802967cf60 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 1 lock held by syz.7.2984/20341: #0: ffff88807bbef3b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff88807bbef3b8 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x182/0x390 mm/gup.c:1942 2 locks held by syz.4.3866/28103: #0: ffffffff8fff55c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fff55c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fff55c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x42a/0x820 net/core/rtnetlink.c:3562 #1: ffffffff8eb63928 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8eb63928 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0x1002/0x1060 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: 12788 Comm: kworker/0:4 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:hrtimer_active+0x4/0x230 kernel/time/hrtimer.c:1854 Code: ff ff e8 0f 62 13 00 90 0f 0b 90 e9 c9 fe ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 41 57 41 56 41 55 41 54 53 48 83 ec 20 48 89 fb e8 d6 61 13 00 RSP: 0018:ffffc90000007bb0 EFLAGS: 00000046 RAX: ffff8880b843ae00 RBX: ffff8880366b9e80 RCX: ffffffff8199391b RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880b843bb80 RBP: dffffc0000000000 R08: ffffffff9054360f R09: 1ffffffff20a86c1 R10: dffffc0000000000 R11: fffffbfff20a86c2 R12: ffff8880b843b060 R13: 0000000000155cc0 R14: ffff8880366ba188 R15: ffff8880b843ae00 FS: 0000000000000000(0000) GS:ffff888124de1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6595fe92f8 CR3: 00000000738d0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 00000000c08e0002 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: hrtick_active kernel/sched/sched.h:3062 [inline] hrtick_update kernel/sched/fair.c:7020 [inline] enqueue_task_fair+0x250d/0x2aa0 kernel/sched/fair.c:7245 enqueue_task+0x75/0x410 kernel/sched/core.c:2160 activate_task kernel/sched/core.c:2200 [inline] ttwu_do_activate+0x1cc/0x660 kernel/sched/core.c:3720 ttwu_queue kernel/sched/core.c:3971 [inline] try_to_wake_up+0x724/0x1390 kernel/sched/core.c:4295 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2190 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3d1/0xa70 kernel/time/hrtimer.c:1994 hrtimer_interrupt+0x435/0x8e0 kernel/time/hrtimer.c:2112 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] __sysvec_apic_timer_interrupt+0x102/0x450 arch/x86/kernel/apic/apic.c:1067 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 52 28 21 00 fb eb 44 e8 4a 28 21 00 e8 85 f8 19 0a 4d 85 f6 74 94 e8 3b 28 21 00 fb 48 c7 c7 20 fb b4 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 3b 17 RSP: 0018:ffffc9000d41f380 EFLAGS: 00000287 RAX: ffffffff81a5cae5 RBX: ffffffff81a5c95f RCX: 0000000000100000 RDX: ffffc90017488000 RSI: 0000000000010adc RDI: ffffffff8eb4fb20 RBP: ffffc9000d41f430 R08: ffffffff905435f7 R09: 1ffffffff20a86be R10: dffffc0000000000 R11: fffffbfff20a86bf R12: 0000000000000000 R13: 000000000000003c R14: 0000000000000200 R15: 1ffff92001a83e74 dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4916 dev_printk_emit+0xee/0x140 drivers/base/core.c:4927 _dev_info+0x11e/0x180 drivers/base/core.c:4985 hub_port_init+0x5e6/0x28d0 drivers/usb/core/hub.c:4996 hub_port_connect drivers/usb/core/hub.c:5496 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x2593/0x4f30 drivers/usb/core/hub.c:5953 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3288 process_scheduled_works kernel/workqueue.c:3379 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3465 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245