------------[ cut here ]------------
WARNING: CPU: 3 PID: 6409 at arch/x86/kvm/../../../virt/kvm/pfncache.c:267 __kvm_gpc_refresh+0x14dd/0x1bb0 virt/kvm/pfncache.c:267
Modules linked in:
CPU: 3 UID: 0 PID: 6409 Comm: syz.0.16 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+0x14dd/0x1bb0 virt/kvm/pfncache.c:267
Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 65 05 00 00 48 8b ad 10 01 00 00 31 db e9 b3 f8 ff ff e8 04 8b 82 00 90 <0f> 0b 90 e9 c4 fa ff ff 48 8b 6c 24 60 e8 f1 8a 82 00 31 db e9 4b
RSP: 0018:ffffc90003c27278 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffffffff813879f6
RDX: ffff888022c64900 RSI: ffffffff81388dfc RDI: 0000000000000000
RBP: ffff88802c9353c0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888000000000
R13: ffff88802c935401 R14: ffff888000000001 R15: ffffc90003c27488
FS:  00007f9058e7a6c0(0000) GS:ffff8880d7170000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9058e81b30 CR3: 0000000038aad000 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:2044 [inline]
 kvm_xen_hvm_evtchn_send+0x22f/0x290 arch/x86/kvm/xen.c:2034
 kvm_arch_vm_ioctl+0x10a0/0x1860 arch/x86/kvm/x86.c:7176
 kvm_vm_ioctl+0x1a91/0x4000 virt/kvm/kvm_main.c:5368
 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+0x18b/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9057f8e929
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:00007f9058e7a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f90581b5fa0 RCX: 00007f9057f8e929
RDX: 0000200000000400 RSI: 00000000400caed0 RDI: 0000000000000005
RBP: 00007f9058010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f90581b5fa0 R15: 00007fffb84f2588
 </TASK>