WARNING: CPU: 3 PID: 3143 at kernel/kthread.c:87 free_kthread_struct+0xa2/0xe0 kernel/kthread.c:87
Kernel panic - not syncing: panic_on_warn set ...

CPU: 3 PID: 3143 Comm: syz-executor5 Not tainted 4.14.0-rc7-next-20171102+ #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1c4/0x1e0 kernel/panic.c:546
 report_bug+0x211/0x2d0 lib/bug.c:183
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
 do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:free_kthread_struct+0xa2/0xe0 kernel/kthread.c:87
RSP: 0018:ffff88006df07768 EFLAGS: 00010206
RAX: ffff880068c28080 RBX: ffff88006afcc840 RCX: ffffffff814937d2
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88006afcc9c8
RBP: ffff88006df07770 R08: ffff88006df1f568 R09: 1ffff1000dbe0ed4
R10: ffff880068c28080 R11: 0000000000000003 R12: 1ffff1000dbe0ef0
R13: 1ffff1000dbe0ef4 R14: 0000000000000000 R15: ffff88006df077e0
 free_task+0x134/0x1a0 kernel/fork.c:390
 __put_task_struct+0x229/0x3b0 kernel/fork.c:663
 put_task_struct include/linux/sched/task.h:95 [inline]
 delayed_put_task_struct+0xca/0x3d0 kernel/exit.c:180
 __rcu_reclaim kernel/rcu/rcu.h:172 [inline]
 rcu_do_batch kernel/rcu/tree.c:2676 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2935 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2902 [inline]
 rcu_process_callbacks+0xd74/0x17d0 kernel/rcu/tree.c:2919
 __do_softirq+0x29d/0xbb2 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1d3/0x210 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:540 [inline]
 smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:577
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline]
RIP: 0010:qlink_free mm/kasan/quarantine.c:150 [inline]
RIP: 0010:qlist_free_all+0xa9/0x160 mm/kasan/quarantine.c:166
RSP: 0018:ffff8800682b76c8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff11
RAX: 0000000000000007 RBX: 0000000000000286 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffff880068c28938 RDI: 0000000000000286
RBP: ffff8800682b7700 R08: ffff88006df1f4c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88006d831c40 R14: ffff88003a67d148 R15: ffffffff85ecb380
 quarantine_reduce+0x141/0x170 mm/kasan/quarantine.c:259
 kasan_kmalloc+0xca/0xe0 mm/kasan/kasan.c:536
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3386 [inline]
 kmem_cache_alloc+0x11b/0x760 mm/slab.c:3546
 alloc_inode+0x128/0x180 fs/inode.c:210
 new_inode_pseudo+0x69/0x190 fs/inode.c:890
 new_inode+0x1c/0x40 fs/inode.c:919
 debugfs_get_inode+0x1b/0x120 fs/debugfs/inode.c:44
 __debugfs_create_file+0x99/0x3e0 fs/debugfs/inode.c:353
 debugfs_create_file+0x57/0x70 fs/debugfs/inode.c:399
 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:592 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3181 [inline]
 kvm_dev_ioctl+0xbb2/0x1890 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3204
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x447c89
RSP: 002b:00007ff4f83c4bd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff4f83c56cc RCX: 0000000000447c89
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 000000000000000a
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff4f83c59c0 R15: 00007ff4f83c5700
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..