On 03/11/17 14:27, Andre Przywara wrote:
> Hi,
>
> good stuff, thanks for doing this!
>
> On 03/11/17 11:38, Jean-Philippe Brucker wrote:
>> GICv2m is a small extension to the GICv2 architecture, specified in the
>> Server Base System Architecture (SBSA). It adds a set of register to
>> converts MSIs into SPIs, effectively enabling MSI support for pre-GICv3
>> platforms.
>
> I was wondering if it would be worth to split this up, and introduce the
> msi_routing_ops in a separate patch first, possibly even the changes to
> pci.c.
>
>> Implement a GICv2m emulation entirely in userspace. Add a thin translation
>> layer in irq.c to catch the MSI->SPI routing setup of the guest, and then
>> transform irqfd injection of MSI into the associated SPI. There shouldn't
>> be any significant runtime overhead compared to gicv3-its.
>
> As others have pointed out already, these patches seem to rely on some
> other patches.
> However by ignoring the two hunks in non-yet-existing functions in irq.c
Right, this was based on the VFIO series and a bit rushed, sorry about
that. A little more work is needed to support irqfd ("irq: add irqfd
helpers") and the combination GICv2m+force-pci+vhost, but it should be
ready soon enough.
Thanks,
Jean
