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Date:   Thu, 30 Sep 2021 09:49:16 +0100
From:   Jean-Philippe Brucker <jean-philippe@linaro.org>
To:     Vivek Kumar Gautam <vivek.gautam@arm.com>
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        Lorenzo.Pieralisi@arm.com, shameerali.kolothum.thodi@huawei.com,
        Alex Williamson <alex.williamson@redhat.com>
Subject: Re: [PATCH RFC v1 01/11] uapi/virtio-iommu: Add page request grp-id
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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