Libguestfs - Dec 2012 - Release notes appendix for libguestfs 1.20 on Fedora 18

I'm just about to release libguestfs 1.20.  This appendix covers
issues specific to Fedora 18.

Fedora 18 defaults to using the libvirt attach-method, meaning that
libvirt is used to create and manage the libguestfs appliance.  There
are several benefits to this (see the full release notes).  You can
switch back to the ordinary method (directly running qemu) at any time
by doing:
  export LIBGUESTFS_ATTACH_METHOD=appliance

There is a bug in libvirt (or perhaps libnl, or somewhere else) which
causes libvirtd to segfault occasionally:
  https://bugzilla.redhat.com/show_bug.cgi?id=875741

You will need selinux-policy >= 3.11.1-63.fc18 and
libvirt >= 0.10.2.1-3.fc18 in order to use SELinux in Enforcing mode
giving you the full benefit of sVirt protection.  I have tested this
and it all works well for me, but please open bugs if you find any
problems.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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software inside the virtual machine.  Supports Linux and Windows.
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On Thu, Dec 13, 2012 at 01:53:24PM +0000, Richard W.M. Jones
wrote:
> I'm just about to release libguestfs 1.20.  This appendix covers
> issues specific to Fedora 18.
> 
> Fedora 18 defaults to using the libvirt attach-method, meaning that
> libvirt is used to create and manage the libguestfs appliance.  There
> are several benefits to this (see the full release notes).  You can
> switch back to the ordinary method (directly running qemu) at any time
> by doing:
>   export LIBGUESTFS_ATTACH_METHOD=appliance
> 
> There is a bug in libvirt (or perhaps libnl, or somewhere else) which
> causes libvirtd to segfault occasionally:
>   https://bugzilla.redhat.com/show_bug.cgi?id=875741
This is jus a dup of the other similar BZ you filed

  https://bugzilla.redhat.com/show_bug.cgi?id=886454

The flaw is netcf, using libnl APIs that are not threadsafe. It is trivially
demonstrated by just having 2 threads call netcf_init/netcf_close in
parallel

Regards,
Daniel
-- 
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On Thu, Dec 13, 2012 at 01:53:24PM +0000, Richard W.M. Jones
wrote:
> I'm just about to release libguestfs 1.20.  This appendix covers
> issues specific to Fedora 18.
> 
> Fedora 18 defaults to using the libvirt attach-method, meaning that
> libvirt is used to create and manage the libguestfs appliance.  There
> are several benefits to this (see the full release notes).  You can
> switch back to the ordinary method (directly running qemu) at any time
> by doing:
>   export LIBGUESTFS_ATTACH_METHOD=appliance
> 
> There is a bug in libvirt (or perhaps libnl, or somewhere else) which
> causes libvirtd to segfault occasionally:
>   https://bugzilla.redhat.com/show_bug.cgi?id=875741
> 
> You will need selinux-policy >= 3.11.1-63.fc18 and
> libvirt >= 0.10.2.1-3.fc18 in order to use SELinux in Enforcing mode
> giving you the full benefit of sVirt protection.  I have tested this
> and it all works well for me, but please open bugs if you find any
> problems.
[This just in ...]

https://bugzilla.redhat.com/show_bug.cgi?id=886915
If you are using Xen as your primary hypervisor on Fedora 18, then
libguestfs may fail with an error:
  unsupported flag 0x2 in function xendaemoncreatexml
Try one of the following solutions:
  export LIBGUESTFS_ATTACH_METHOD=libvirt:qemu:///session
or:
  export LIBGUESTFS_ATTACH_METHOD=appliance

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top

Also I accidentally compiled out LDM (Windows dynamic disk) support in
the first Fedora 18 package.  This will be fixed in a few days in the
1.20.1 [not yet released] build.

https://bugzilla.redhat.com/show_bug.cgi?id=887812

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming blog: http://rwmj.wordpress.com
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