[Libguestfs] hang after seabios

[Richard W.M. Jones]

On Thu, Jul 31, 2014 at 03:32:18PM -0700, Zetan Drableg wrote:
> Ok -
> By the way, I looked into updating out KVM versions. Since we already
> have so many KVM servers of this version in production, I can't easily
> forklift update everything without much testing.
> 
> exec /usr/libexec/qemu-kvm -s -S "$@"
> 
> export LIBGUESTFS_HV=/root/work/qemu-wrapper
> export LIBGUESTFS_BACKEND=direct
> 
> How do I simulate the setup of devices the test tool perform?
> Just copy/pasting the qemu-kvm argument list doesn't work.
> 
> I was hoping that LIBGUESTFS_HV would replace usage of
> /usr/libexec/qemu-kvm with /root/work/qemu-wrapper, but does not
> appear to

OK I think the problem is that it's libguestfs 1.20, where the
environment variable names are different (check guestfs(3) in your
local copy).  This should work:

  export LIBGUESTFS_ATTACH_METHOD=appliance
  export LIBGUESTFS_QEMU=/root/work/qemu-wrapper

There's an additional problem which is you need the wrapper to
distinguish between -help and -version tests and the final command.
Use a wrapper like this:

----------------------------------------------------------------------
#!/bin/bash -

qemu=/usr/libexec/qemu-kvm

if ! echo "$@" | grep -sqE -- '-help|-version'; then
  echo QEMU debugging enabled.
  debug="-s -S"
fi

exec $qemu $debug "$@"
----------------------------------------------------------------------

The wrapper must be executable.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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