Re: [libvirt] [PATCH v5 4/4] news.xml: add address type='unassigned' entry

On Tue, 17 Dec 2019 16:06:47 -0300 Daniel Henrique Barboza <danielhb413(a)gmail.com&gt; wrote: > Signed-off-by: Daniel Henrique Barboza <danielhb413(a)gmail.com&gt; > --- > docs/news.xml | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/docs/news.xml b/docs/news.xml > index 2a25b6ca49..febda970f6 100644 > --- a/docs/news.xml > +++ b/docs/news.xml > @@ -54,6 +54,20 @@ > written in the RST as an alternative to HTML. > </description> > </change> > + <change> > + <summary> > + new PCI hostdev address type: unassigned > + </summary> > + <description> > + A new PCI hostdev address type 'unassigned' is introduced, > + giving users the option to choose which PCI hostdevs > + within the same IOMMU group will not be assigned to the > + guest. PCI hostdevs that shouldn't be used by the guest > + can be classified as <code>address type='unassigned'</code>. > + Libvirt will still be able to manage the device as a > + regular PCI hostdev. > + </description> This is rather convoluted. Users have always had the choice of which devices NOT to assign. I would present this as a mechanism for libvirt to manage the driver binding of devices, as done for managed PCI hostdev devices, without actually attaching the devices to the VM, thereby facilitating device assignment when only a subset of the devices within an IOMMU group are intended to be used by the guest.

BTW, this should also work with the hostdev <driver='kvm'/> option if the user wanted to bind the device to pci-stub rather than vfio-pci to provide even further isolation from the user being able to access the device. Thanks,

Alex > + </change> > </section> > <section title="Improvements"> > <change>