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Subject: Re: [PATCH v2 1/4] x86/mm: Export force_dma_unencrypted
To:     Christoph Hellwig <hch@infradead.org>
Cc:     dri-devel@lists.freedesktop.org, pv-drivers@vmware.com,
        linux-graphics-maintainer@vmware.com, linux-kernel@vger.kernel.org,
        Thomas Hellstrom <thellstrom@vmware.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
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From:   =?UTF-8?Q?Thomas_Hellstr=c3=b6m_=28VMware=29?= 
        <thomas_os@shipmail.org>
Organization: VMware Inc.
Message-ID: <4cb5a2b4-cbd0-a86d-7881-f3d750df7d0e@shipmail.org>
Date:   Wed, 4 Sep 2019 19:28:16 +0200
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On 9/4/19 2:22 PM, Christoph Hellwig wrote:
> On Wed, Sep 04, 2019 at 09:32:30AM +0200, Thomas Hellström (VMware) wrote:
>> That sounds great. Is there anything I can do to help out? I thought this
>> was more or less a dead end since the current dma_mmap_ API requires the
>> mmap_sem to be held in write mode (modifying the vma->vm_flags) whereas
>> fault() only offers read mode. But that would definitely work.
> We'll just need to split into a setup and faul phase.  I have some
> sketches from a while ago, let me dust them off so that you can
> try them.

I'd be happy to.

Thanks,

Thomas