[fedora-virt] Directory Passthrough

[Richard W.M. Jones]

On Mon, Mar 17, 2014 at 11:22:34AM +0000, Richard W.M. Jones wrote:
> [A shared filesystem sounds like what you want, but given that qemu
> only has 9pfs and the KVM team have deemed that this is unsupportable,
> read on ...]

Just to follow up on this point.  There is a bug about this
(RHBZ#816603) although I suspect that you won't be able to read the
important (private) comments there.  In summary the reasons we disable
this are:

- There's no driver support (except in recent Linux).  This means
  that, for example, Windows guests would not be able to see the
  shared filesystem, nor even older RHEL.

- The 9p code upstream is large, unfamiliar, and appears to be a dead
  end upstream.  This makes it a security and maintenance headache.

What interesting for me is that filesystem passthrough is usually
considered a desktop feature.  It's something that VirtualBox - for
example - does well, but not something we've considered useful for
servers.  However you are using it for a server.

Rich

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
libguestfs lets you edit virtual machines.  Supports shell scripting,
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