INFO: task syz.9.4274:26026 blocked for more than 143 seconds. Tainted: G U L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.4274 state:D stack:25608 pid:26026 tgid:26015 ppid:22217 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 kvm_swap_active_memslots+0x2ea/0x7d0 virt/kvm/kvm_main.c:1643 kvm_activate_memslot virt/kvm/kvm_main.c:1802 [inline] kvm_create_memslot virt/kvm/kvm_main.c:1868 [inline] kvm_set_memslot+0xd70/0x15c0 virt/kvm/kvm_main.c:1980 kvm_set_memory_region+0xe4a/0x15e0 virt/kvm/kvm_main.c:2136 kvm_set_internal_memslot+0x9f/0xe0 virt/kvm/kvm_main.c:2159 __x86_set_memory_region+0x2f6/0x740 arch/x86/kvm/x86.c:13285 kvm_alloc_apic_access_page+0xc5/0x140 arch/x86/kvm/lapic.c:2806 vmx_vcpu_create+0x503/0xbd0 arch/x86/kvm/vmx/vmx.c:7637 kvm_arch_vcpu_create+0x688/0xb20 arch/x86/kvm/x86.c:12733 kvm_vm_ioctl_create_vcpu virt/kvm/kvm_main.c:4223 [inline] kvm_vm_ioctl+0x105e/0x4090 virt/kvm/kvm_main.c:5180 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f11a1f8f7c9 RSP: 002b:00007f11a2d3e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f11a21e6180 RCX: 00007f11a1f8f7c9 RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000003 RBP: 00007f11a2013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f11a21e6218 R14: 00007f11a21e6180 R15: 00007ffd5d525428 INFO: task syz.9.4274:26032 blocked for more than 144 seconds. Tainted: G U L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.4274 state:D stack:27368 pid:26032 tgid:26015 ppid:22217 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776 class_mutex_constructor include/linux/mutex.h:253 [inline] kvm_alloc_apic_access_page+0x27/0x140 arch/x86/kvm/lapic.c:2800 vmx_vcpu_create+0x503/0xbd0 arch/x86/kvm/vmx/vmx.c:7637 kvm_arch_vcpu_create+0x688/0xb20 arch/x86/kvm/x86.c:12733 kvm_vm_ioctl_create_vcpu virt/kvm/kvm_main.c:4223 [inline] kvm_vm_ioctl+0x105e/0x4090 virt/kvm/kvm_main.c:5180 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f11a1f8f7c9 RSP: 002b:00007f119f9d1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f11a21e6360 RCX: 00007f11a1f8f7c9 RDX: 0000000000000004 RSI: 000000000000ae41 RDI: 0000000000000003 RBP: 00007f11a2013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f11a21e63f8 R14: 00007f11a21e6360 R15: 00007ffd5d525428 Showing all locks held in the system: 1 lock held by khungtaskd/32: #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/10822: #0: ffff888035c550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031622f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211 2 locks held by syz.9.4274/26026: #0: ffff88805c94c0a8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffff88805c94c0a8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_alloc_apic_access_page+0x27/0x140 arch/x86/kvm/lapic.c:2800 #1: ffff88805c94c138 (&kvm->slots_arch_lock){+.+.}-{4:4}, at: kvm_set_memslot+0x34/0x15c0 virt/kvm/kvm_main.c:1931 1 lock held by syz.9.4274/26032: #0: ffff88805c94c0a8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffff88805c94c0a8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_alloc_apic_access_page+0x27/0x140 arch/x86/kvm/lapic.c:2800 1 lock held by syz.8.4445/26886: 3 locks held by syz.2.4777/28489: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x133/0x180 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xe66/0x1180 kernel/hung_task.c:515 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246