------------[ cut here ]------------
WARNING: arch/x86/kvm/../../../virt/kvm/pfncache.c:267 at __kvm_gpc_refresh+0x1b21/0x2490 virt/kvm/pfncache.c:267, CPU#2: syz.3.912/9100
Modules linked in:
CPU: 2 UID: 0 PID: 9100 Comm: syz.3.912 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__kvm_gpc_refresh+0x1b21/0x2490 virt/kvm/pfncache.c:267
Code: 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 67 09 00 00 48 8b 04 24 31 db 48 8b a8 10 01 00 00 e9 f2 ef ff ff e8 10 cb 85 00 90 <0f> 0b 90 e9 92 f7 ff ff e8 02 cb 85 00 48 85 db 0f 84 b4 04 00 00
RSP: 0018:ffffc90003797608 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffffffff81390119
RDX: ffff88802a604980 RSI: ffffffff81391b60 RDI: 0000000000000000
RBP: ffffffffffffff01 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000001 R11: ffff88802a6054b0 R12: ffff888000000000
R13: ffff888000000001 R14: ffff888000000000 R15: ffffc90003797870
FS:  00007f079459c6c0(0000) GS:ffff8880d6af5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c370053 CR3: 0000000033a41000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 kvm_gpc_refresh+0xec/0x190 virt/kvm/pfncache.c:382
 kvm_xen_set_evtchn.part.0+0x19c/0x270 arch/x86/kvm/xen.c:1943
 kvm_xen_set_evtchn arch/x86/kvm/xen.c:1961 [inline]
 evtchn_set_fn+0x69/0x90 arch/x86/kvm/xen.c:1960
 kvm_set_irq+0x244/0x490 virt/kvm/irqchip.c:88
 kvm_vm_ioctl_irq_line+0xc6/0x160 arch/x86/kvm/irq.c:285
 kvm_vm_ioctl+0xb1b/0x4090 virt/kvm/kvm_main.c:5304
 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: 0033:0x7f079378f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f079459c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f07939e6090 RCX: 00007f079378f7c9
RDX: 0000200000000000 RSI: 00000000c008ae67 RDI: 0000000000000005
RBP: 00007f0793813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f07939e6128 R14: 00007f07939e6090 R15: 00007ffdf0c51768
 </TASK>