INFO: task syz-executor:7305 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20968 pid:7305 tgid:7305 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 netfs_wait_for_outstanding_io include/linux/netfs.h:552 [inline] v9fs_evict_inode+0x170/0x320 fs/9p/vfs_inode.c:348 evict+0x504/0x9c0 fs/inode.c:810 dispose_list fs/inode.c:852 [inline] evict_inodes+0x64c/0x6d0 fs/inode.c:906 generic_shutdown_super+0x9a/0x2c0 fs/super.c:627 kill_anon_super+0x3b/0x70 fs/super.c:1281 v9fs_kill_super+0x4c/0x90 fs/9p/vfs_super.c:195 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb57e98fed7 RSP: 002b:00007ffda0f7bc38 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fb57ea11c05 RCX: 00007fb57e98fed7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffda0f7bcf0 RBP: 00007ffda0f7bcf0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffda0f7cd80 R13: 00007fb57ea11c05 R14: 0000000000037184 R15: 00007ffda0f7cdc0 Showing all locks held in the system: 1 lock held by khungtaskd/32: #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/1:2/918: #0: ffff888145289d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888145289d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003827ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003827ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888028363198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888028363198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 2 locks held by getty/5623: #0: ffff88814ddd40a0 (&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 1 lock held by syz-executor/7305: #0: ffff88807dff40e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807dff40e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807dff40e0 (&type->s_umount_key#58){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 1 lock held by syz.7.845/9047: #0: ffff88807dff40e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88807dff40e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.9.1199/10724: #0: ffff88802a53d330 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x22e/0xe90 virt/kvm/kvm_main.c:4444 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 10778 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline] RIP: 0010:check_preemption_disabled+0x5c/0x120 lib/smp_processor_id.c:19 Code: 14 5c 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c8 65 4c 8b 3c 25 08 40 e8 92 41 f6 47 2f RSP: 0018:ffffc90002e772e8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8de9a670 RDI: ffffffff8c050f00 RBP: ffffffff81ab0e0d R08: 0000000000000000 R09: ffffffff81ab0e0d R10: ffffc90002e77498 R11: ffffffff81ac9640 R12: 0000000000000002 R13: ffffffff8e53d360 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff88812579c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd2df68858 CR3: 000000007ecea000 CR4: 00000000003526f0 DR0: fffffffffffffff8 DR1: 0000000000000006 DR2: 0200000000000000 DR3: 0000000000000003 DR6: 00000000ffff0ff0 DR7: 0000000000000400 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:1169 [inline] is_module_text_address+0x39/0x1e0 kernel/module/main.c:3845 kernel_text_address+0x94/0xe0 kernel/extable.c:119 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559 slab_free_hook mm/slub.c:2467 [inline] slab_free mm/slub.c:6542 [inline] kmem_cache_free+0x4a2/0x690 mm/slub.c:6653 anon_vma_free mm/rmap.c:136 [inline] __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2764 put_anon_vma include/linux/rmap.h:117 [inline] unlink_anon_vmas+0x503/0x670 mm/rmap.c:443 free_pgtables+0x72b/0x9c0 mm/memory.c:413 exit_mmap+0x43c/0xb40 mm/mmap.c:1291 __mmput+0x118/0x430 kernel/fork.c:1148 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:954 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1118 [inline] __se_sys_exit_group kernel/exit.c:1116 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116 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/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f925562c6c5 Code: Unable to access opcode bytes at 0x7f925562c69b. RSP: 002b:00007ffd2df68ef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007ffd2df69204 RCX: 00007f925562c6c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000003 R08: 00007ffd2df68ff0 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffd2df69230 R14: 00007f925583c000 R15: 000055f40937bd98