Comment 5 for bug 1310714

I believe this is the issue i am seeing as well. QEMU continues to consume memory (>6GB) until the host machine runs out of memory (I am also using slirp for networking). I am able to reproduce it from qemu 2.5 (version found in apt-get for ubuntu 16.04.3 LTS) and I verified it exists after I compiled from source both 2.8.1.1 and 2.10.2 as well.

$ uname -a
Linux siemens 4.4.0-104-generic #127-Ubuntu SMP Mon Dec 11 12:16:42 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

$ cat qemu.cfg
# qemu config file

[drive]
  format = "raw"
  file = "qemu_rootfs_512.img"

[drive]
  format = "raw"
  file = "hmi_sl_oa.img"

[drive]
  format = "raw"
  file = "swap_512m.img"

[net]
  type = "nic"

[net]
  type = "user"

[machine]
  kernel = "vmlinuz-2.6.11.12-vanilla.bz"
  initrd = "initrd-2.6.11.12.img.gz"
  append = "root=/dev/hda"

[memory]
  size = "2048"

[vnc "default"]
  vnc = ":1"

$ qemu-system-x86_64 -readconfig qemu.cfg

Let me know what other information you need.