Re: [PATCH] vfio-pci: Disable binding to PFs with SR-IOV enabled

[Peter Xu]

On Thu, Jul 12, 2018 at 04:33:04PM -0600, Alex Williamson wrote:
> We expect to receive PFs with SR-IOV disabled, however some host
> drivers leave SR-IOV enabled at unbind.  This puts us in a state where
> we can potentially assign both the PF and the VF, leading to both
> functionality as well as security concerns due to lack of managing the
> SR-IOV state as well as vendor dependent isolation from the PF to VF.
> If we were to attempt to actively disable SR-IOV on driver probe, we
> risk VF bound drivers blocking, potentially risking live lock
> scenarios.  Therefore simply refuse to bind to PFs with SR-IOV enabled
> with a warning message indicating the issue.  Users can resolve this
> by re-binding to the host driver and disabling SR-IOV before
> attempting to use the device with vfio-pci.
> 
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>

Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>

-- 
Peter Xu