[libvirt] lxcContainerResolveSymlinks failing on cascading FS

[Cedric Bosdonnat]

Hi all,

As an example, the following command

    virt-sandbox-service create --network dhcp,source=default --unitfile sshd.service mysshd -i 512

generates a container definition containing these filesystems (in the
same order):

    <filesystem type='file' accessmode='passthrough'>
      <source file='/var/lib/libvirt/images/mysshd.raw'/>
      <target dir='/var/lib/libvirt/filesystems/mysshd'/>
    </filesystem>
    <filesystem type='bind' accessmode='passthrough'>
      <source dir='/var/lib/libvirt/filesystems/mysshd/var'/>
      <target dir='/var'/>
    </filesystem>

Since /var/lib/libvirt/filesystems/mysshd contains nothing, the second
FS needs the first one to be mounted for the source directory to exist.

The problem comes with lxcContainerResolveSymlinks() being run before
any file system is actually mounted. So the container can't be started
and we get the following error:

    Failed to access '/var/lib/libvirt/filesystems/mysshd/var': No such file or directory

This would work if the symlinks were resolved right before mounting the
FS instead of before mounting any of them. Any strong opinion against
it?

--
Cedric