assert in virtio-iommu

Host environment

• Operating system: Ubuntu 22.04.4 LTS

• OS/kernel version: Linux 6.5.0-25-generic

• Architecture: aarch64

• QEMU flavor: 9.0.0

• QEMU version: commit 7e1c0047

• QEMU command line:

  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

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