Comment 22 for bug 420423

can we continue the discussion on lkml about whether barrier support should be required?

response from hch was:

  virtio_blk on kvm does not support any barriers at all, similar to many
  other drivers out there. If the queue flags say we don't support
  barriers higher layers should not submit any barrier requests.

wrt. immediate F-12 concerns, we should focus on getting rid of these errors