Re: [Qemu-devel] [PATCH 0/6] Misc PCI cleanups

[Michael S. Tsirkin]

On Mon, Oct 08, 2012 at 09:58:32AM -0600, Alex Williamson wrote:
> Michael, Jan,
> 
> Any comments on these?  I'd like to make the PCI changes before I update
> vfio-pci to make use of the new resampling irqfd in kvm.  We don't have
> anyone officially listed as maintainer of pci-assign since it's been
> moved to qemu.  I could include the pci-assign patches in my tree if you
> prefer.  Thanks,
> 
> Alex

Patches themselves look fine, but I'd like to
better understand why do we want the INTx fallback.
Isn't it easier to add intx routing support?

> On Tue, 2012-10-02 at 13:21 -0600, Alex Williamson wrote:
> > A few cleanups that I'll also apply to vfio-pci.  First make intx
> > route checking non-fatal.  vfio-pci has a fallback INTx mechanism
> > that doesn't rely on this, so we can already run on q35, but not if
> > we can't even probe for intx routing w/o blowing up.  Next, both
> > vfio-pci and pci-assign test whether INTx routing has changed using
> > similar functions.  Make this common.  Finally, expose a way to
> > get the MSI message for an MSI vector.  Again, both pci-assign and
> > vfio-pci need to do this to program the vector for KVM injection.
> > Thanks,
> > 
> > Alex
> > 
> > ---
> > 
> > Alex Williamson (6):
> >       pci-assign: Use msi_get_message()
> >       msi: Add msi_get_message()
> >       pci-assign: Use pci_intx_route_changed()
> >       pci: Helper function for testing if an INTx route changed
> >       pci-assign: Add support for no-route
> >       pci: Add INTx no-route option
> > 
> > 
> >  hw/kvm/pci-assign.c |   14 ++++++++------
> >  hw/msi.c            |   45 +++++++++++++++++++++++++++++----------------
> >  hw/msi.h            |    1 +
> >  hw/pci.c            |   13 +++++++++++--
> >  hw/pci.h            |    2 ++
> >  5 files changed, 51 insertions(+), 24 deletions(-)
> 
>