On 2023/12/12 23:27, Jason Gunthorpe wrote:
On Mon, Dec 11, 2023 at 08:39:46PM -0700, Alex Williamson wrote:
So how do we keep up with PCIe spec updates relative to the PASID
capability with this proposal? Would it make more sense to report the
raw capability register and capability version rather that a translated
copy thereof? Perhaps just masking the fields we're currently prepared
to expose.
I think the VMM must always create a cap based on the PCIe version it
understands. We don't know what future specs will put there so it
seems risky to forward it if we don't know that any possible
hypervisor support is present.
This series parses the capability register and reports the known caps
to user. While this does not include the version number, userspace should
decide the proper version number. Seems like what you suggests here.
We have this problem on and off where stuff in PCI config space needs
explicit hypervisor support or it doesn't work in the VM and things
get confusing.
Jason
--
Regards,
Yi Liu
