[Pkg-libvirt-maintainers] Bug#819331: libvirt0: fails to start KVM instance using readonly ISO image

[Simon Richter]

Package: libvirt0
Version: 1.2.9-9+deb8u1
Severity: normal

Hi,

I'm trying to start a KVM instance, booting from a CD-ROM ISO image that is
stored on a network server, and readonly for the VM host machine.

Using the definition

    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='/mnt/boot.iso'/>
      <target dev='sdb' bus='scsi'/>
      <readonly/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>

I'd expect to be able to boot, but I get

error: Failed to start domain Test
error: unable to set user and group to '108:119' on '/mnt/boot.iso': Permission denied

Setting the <shareable/> attribute does not help.

It would be great if there was a way to use readonly CD-ROM images without
requiring write access to them.

   Simon

-- System Information:
Debian Release: 8.3
  APT prefers stable
  APT policy: (990, 'stable')
Architecture: amd64 (x86_64)

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

Versions of packages libvirt0 depends on:
ii  libapparmor1        2.9.0-3
ii  libaudit1           1:2.4-1+b1
ii  libavahi-client3    0.6.31-5
ii  libavahi-common3    0.6.31-5
ii  libc6               2.19-18+deb8u3
ii  libcap-ng0          0.7.4-2
ii  libdbus-1-3         1.8.20-0+deb8u1
ii  libdevmapper1.02.1  2:1.02.90-2.2
ii  libgnutls-deb0-28   3.3.8-6+deb8u3
ii  libnl-3-200         3.2.24-2
ii  libnl-route-3-200   3.2.24-2
ii  libnuma1            2.0.10-1
ii  libsasl2-2          2.1.26.dfsg1-13+deb8u1
ii  libselinux1         2.3-2
ii  libssh2-1           1.4.3-4.1+deb8u1
ii  libsystemd0         215-17+deb8u3
ii  libxml2             2.9.1+dfsg1-5+deb8u1
ii  libyajl2            2.1.0-2

Versions of packages libvirt0 recommends:
ii  lvm2  2.02.111-2.2

libvirt0 suggests no packages.

-- no debconf information