[Vmdebootstrap-devel] Bug#774588: VM hangs on boot with extlinux and large image

[Christian Kastner]

Package: vmdebootstrap
Version: 0.5-1
Severity: important

Hi,

When following the usage example from vmdebootstrap(8), qemu fails to
boot an image if that image is a bit larger than 1GB and extlinux is
used. It just hangs at the SeaBIOS screen, whilst using 100% of a CPU
core, with the following message:

  "Booting from Hard Disk..."

Steps to reproduce:

  1073MB image is still OK (for me):
    $ sudo vmdebootstrap --image ok.img --size 1073M --owner=`whoami`
    $ qemu-system-x86_64 ./ok.img

  1074MB image, and larger, hangs:
    $ sudo vmdebootstrap --image hang.img --size 1074M --owner=`whoami`
    $ qemu-system-x86_64 ./hang.img

Using a separate /boot partition with eg --bootsize=50M did not resolve
the issue for me. Using --grub did, however.

I'm not sure who the culprit is: extlinux, vmdebootstrap, qemu,
qemu-utils, or seabios. Please reassign at will. In case this is an
extlinux limitation, though, then perhaps --grub should be forced with
size > 1g? I couldn't find any docs on that, however.

Regards,
Christian


-- System Information:
Debian Release: 8.0
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages vmdebootstrap depends on:
ii  debootstrap    1.0.66
ii  extlinux       3:6.03+dfsg-4
ii  kpartx         0.5.0-5
ii  parted         3.2-6
ii  python-cliapp  1.20140719-1
pn  python:any     <none>
ii  qemu-utils     1:2.1+dfsg-11

Versions of packages vmdebootstrap recommends:
ii  grub2-common      2.02~beta2-19
pn  qemu-system       <none>
ii  qemu-user-static  1:2.1+dfsg-11
ii  squashfs-tools    1:4.2+20130409-2

vmdebootstrap suggests no packages.

-- no debconf information