Re: [virtio-dev] Memory sharing device

[Gerd Hoffmann <kraxel@redhat.com>]

  Hi,

> > Note:  I think using a pci memory bar (aka host memory mapped into the
> > guest) as backing storage for dma-bufs isn't going to work.
> 
> (Not knowing dma-bufs) but could you explain why?

Many places in the linux kernel assume dma-bufs are built out of normal
ram pages (i.e. something backed by struct page).  Which is not the case
for pci memory bars which are typically ioremapped() (completely or in
chunks) to access them.

cheers,
  Gerd