[Virtio-fs] [PATCH] docs: describe the security considerations with virtiofsd xattr mapping

[Harry G. Coin]

On 6/15/21 10:46 AM, Daniel P. Berrangé wrote, in part:
>  - Don't use xattrs at all for remapping, instead use
>    hidden files.

As not every host filesystem will have xattrs, or have xattrs enabled: 
Isn't something like the above required of virtiofsd anyway?

Also, for security, you might consider creating a parallel hidden
directory tree 'beside' the shared root (so not exposed to the guest)
then put the xattrs in files there.  So if /var/shared/foo is visible to
the guest, /var/shared/.foo.guest_xattrs/ parallels that.