x86: 0.937
device: 0.901
graphic: 0.756
hypervisor: 0.737
virtual: 0.677
performance: 0.618
semantic: 0.599
i386: 0.497
PID: 0.444
architecture: 0.432
socket: 0.413
debug: 0.412
ppc: 0.405
mistranslation: 0.386
kernel: 0.327
peripherals: 0.319
network: 0.309
vnc: 0.302
register: 0.294
VMM: 0.251
user-level: 0.208
TCG: 0.192
risc-v: 0.188
assembly: 0.183
arm: 0.170
KVM: 0.148
permissions: 0.148
files: 0.119
boot: 0.114

assert in virtio-iommu
Description of problem:
The following log reveals it:

```
qemu-system-x86_64: qemu/hw/virtio/virtio-iommu.c:821: void virtio_iommu_handle_command(VirtIODevice *, VirtQueue *): Assertion `sz == output_size' failed.
Aborted
```
Steps to reproduce:
```
cat << EOF | \qemu-system-x86_64 \
-display none -machine accel=qtest -m 512M -machine q35 -nodefaults \
-device virtio-iommu -qtest stdio
outl 0xcf8 0x80000804
outw 0xcfc 0x06
outl 0xcf8 0x80000820
outl 0xcfc 0xe0004000
write 0x10000e 0x1 0x01
write 0xe0004020 0x4 0x00001000
write 0xe0004028 0x4 0x00101000
write 0xe000401c 0x1 0x01
write 0x106000 0x1 0x05
write 0x100001 0x1 0x60
write 0x100002 0x1 0x10
write 0x100009 0x1 0x04
write 0x10000c 0x1 0x01
write 0x100018 0x1 0x04
write 0x10001c 0x1 0x02
write 0x101003 0x1 0x01
write 0xe0007001 0x1 0x00
EOF
```