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From:   Peng Fan <peng.fan@nxp.com>
To:     "Michael S. Tsirkin" <mst@redhat.com>
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Subject: RE: [PATCH] xen: introduce xen_vring_use_dma
Thread-Topic: [PATCH] xen: introduce xen_vring_use_dma
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Date:   Mon, 29 Jun 2020 06:35:48 +0000
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> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma
>=20
> On Mon, Jun 29, 2020 at 06:25:41AM +0000, Peng Fan wrote:
> > > > > > Anyway, re-reading the last messages of the original thread
> > > > > > [1], it looks like Peng had a clear idea on how to fix the gene=
ral issue.
> > > > > > Peng, what happened with that?
> > > >
> > > > We shrinked the rpmsg reserved area to workaround the issue.
> > > > So still use the dma apis in rpmsg.
> > > >
> > > > But here I am going to address domu android trusty issue using virt=
io.
> > >
> > > My suggestion is to first of all fix DMA API so it works properly.
> >
> > Could you please elaborate more details?
> >
> > You mean the DMA API usage of rpmsg? Or xen domu dma_ops?
> >
> > Thanks,
> > Peng.
>=20
> Not 100% sure but I think xen dma ops.

Sorry to ask again, could you explain more details about what issues
do you see of current xen ARM domu dma_ops?=20
Or Dom0 swiotlb xen dma_ops?

Thanks,
Pen.g

>=20
> --
> MST