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Date:   Tue, 3 Sep 2019 17:18:50 +0200
From:   Daniel Vetter <daniel@ffwll.ch>
To:     Thomas =?iso-8859-1?Q?Hellstr=F6m_=28VMware=29?= 
        <thomas_os@shipmail.org>
Cc:     dri-devel@lists.freedesktop.org, pv-drivers@vmware.com,
        linux-graphics-maintainer@vmware.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/4] Have TTM support SEV encryption with coherent
 memory
Message-ID: <20190903151850.GB2112@phenom.ffwll.local>
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On Tue, Sep 03, 2019 at 03:15:00PM +0200, Thomas Hellstr?m (VMware) wrote:
> With SEV memory encryption and in some cases also with SME memory
> encryption, coherent memory is unencrypted. In those cases, TTM doesn't
> set up the correct page protection. Fix this by having the TTM
> coherent page allocator call into the platform code to determine whether
> coherent memory is encrypted or not, and modify the page protection if
> it is not.
> 
> v2:
> - Use force_dma_unencrypted() rather than sev_active() to catch also the
>   special SME encryption cases.

We should probably cc Christoph Hellwig on this ... better to hear his
screams before merging than afterwards. As much as I don't support
screaming maintainers, that seems the least bad option here.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch