libguestfs crashes with softlinked /tmp

libguestfs-test-tool error looks like this:

mkdtemp: /tmp/lvmUv4KRW: No such file or directory
[    1.846456] Unregister pv shared memory for cpu 0
[    1.847678] kvm: exiting hardware virtualization
[    1.848892] sd 2:0:1:0: [sdb] Synchronizing SCSI cache
[    1.850342] sd 2:0:0:0: [sda] Synchronizing SCSI cache
[    1.852824] reboot: Restarting system
[    1.853706] reboot: machine restart
libguestfs: error: appliance closed the connection unexpectedly, see earlier error messages

if the /tmp directory is a softlink. So if you nee more space in /tmp, don't softlink, use mount:

mount --bind /path/to/free/space /tmp