Bug 1277744

Please run:

  sudo virt-filesystems -v -x -a /path/to/a/virtual_hd.vmdk 2>&1 | tee virt-filesystems.log

and attach to this bug the resulting virt-filesystems.log you get. Enabling debug and verbosity will not cause virt-filesystems to work while it didn't without, but at least we can see what's the actual issue in this case.

Created attachment 1241525 [details]
When no VirtualBox VMs with vmdk disk is running

virt-filesystems works wnen no VirtualBoxe's VM is running with qcow/qcow2 or vmdk VHD.

Created attachment 1241526 [details]
When VirtualBox VMs with vmdk disk is running

virt-filesystems doesn't work, wnen VirtualBoxe's VM is running with qcow/qcow2 or vmdk VHD.

I've added 2 attachments of logs from running those commands:
/tmp/virt-filesystems.log - is when no VB's VM is running with vmdk/qcow/qcow2 disk in it.
/tmp/virt-filesystems-vb.log - is when VB's VM is running with vmdk/qcow/qcow2 disk in it.

P.S. VBoxe's VM can have any OS, installed in it. As long as I attach a vmdk/qcow/qcow2 disk to it, the virt-filesystems reveals it's problem.

I am running Ubuntu 16.04 now with kernel: 4.4.0-57-generic x86_64
virt-filesystems 1.32.2
VirtualBox V5.0.20 r106931

The error is:

  ioctl(KVM_CREATE_VM) failed: 16 Device or resource busy
  failed to initialize KVM: Device or resource busy
  Back to tcg accelerator.
  qemu-system-x86_64: CPU model 'host' requires KVM

This is unfortunate, but it's a real (and very long-standing) bug
in qemu.

The workaround is to set:

  export LIBGUESTFS_BACKEND_SETTINGS=force_tcg

which forces libguestfs to use software emulation.  You only need
to use this when using VirtualBox (and also note that it'll make
libguestfs run a lot slower).

The actual reason why this is happening is best explained by pointing
to the comment in the libguestfs code:

https://github.com/libguestfs/libguestfs/blob/dd519e8a8ea2be89862f3cec99aff9e19c458afa/src/appliance-cpu.c#L64-L66

I filed a qemu RFE about this:

https://bugs.launchpad.net/qemu/+bug/1657010

So, meanwhile, I can probably put it in a rough script, like that, I guess:

var_vbproc=$(pgrep -f '/virtualbox/VirtualBox.*--startvm\>'|wc -l)
if [ "$var_vbproc" -gt 0 ]; then
	export LIBGUESTFS_BACKEND_SETTINGS=force_tcg
fi
virt-filesystems $1 $2 $3 $4 $5 $6 $7 $8 $9
if [ "$var_vbproc" -gt 0 ]; then
	export LIBGUESTFS_BACKEND_SETTINGS=''
fi

It worked and I am not very good at bash. Shortly after testing this script, I realized, that exported variable lives only during script's execution, so, I've simplified it a bit (unfortunately, I cannot edit the previous comment):

if [ "$(pgrep -f '/virtualbox/VirtualBox.*--startvm\>'|wc -l)" -gt 0 ]; then
        export LIBGUESTFS_BACKEND_SETTINGS='force_tcg'
fi
virt-filesystems $1 $2 $3 $4 $5 $6 $7 $8 $9

I suspect that the fix for bug 1605071 which went upstream in around Sept 2018
has also fixed this.

This product has been discontinued or is no longer tracked in Red Hat Bugzilla.

Reopening because Virtualization Tools has not been discontinued.