Re: [PATCH RFC v1 01/11] uapi/virtio-iommu: Add page request grp-id and flags information

From: Jean-Philippe Brucker
Date: Thu Sep 30 2021 - 04:49:42 EST


On Thu, Sep 30, 2021 at 10:26:35AM +0530, Vivek Kumar Gautam wrote:
> > I'm not sure why we made it 32-bit in Linux UAPI, it's a little wasteful.
> > PCIe PRGI is 9-bits and SMMU STAG is 16-bits. Since the scope of the grpid
> > is the endpoint, 16-bit means 64k in-flight faults per endpoint, which
> > seems more than enough.
>
> Right, I will update this to 16-bits field. It won't be okay to update the
> iommu uAPI now, right?

Since there is no UAPI transport for the fault request/response at the
moment, it should be possible to update it.

Thanks,
Jean