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Date:   Tue, 13 Nov 2018 12:36:16 +0200
From:   Mika Westerberg <mika.westerberg@linux.intel.com>
To:     Mario.Limonciello@dell.com
Cc:     iommu@lists.linux-foundation.org, joro@8bytes.org,
        dwmw2@infradead.org, baolu.lu@linux.intel.com, ashok.raj@intel.com,
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        YehezkelShB@gmail.com, lukas@wunner.de, ckellner@redhat.com,
        anthony.wong@canonical.com, linux-acpi@vger.kernel.org,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/4] thunderbolt: Export IOMMU based DMA protection
 support to userspace
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 <20181112160628.86620-5-mika.westerberg@linux.intel.com>
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On Mon, Nov 12, 2018 at 04:22:25PM +0000, Mario.Limonciello@dell.com wrote:
> > +DMA protection utilizing IOMMU
> > +------------------------------
> > +Recent systems shipping with Windows 10 version 1803 or later may support a
> > +feature called `Kernel DMA Protection for Thunderbolt 3`_.  This means that
> 
> Keep in mind there will be systems that ship with Linux that enable this feature too ;)

Yes, you are absolutely right. I sometimes forgot that fact ;-)

> It might be better to make it time frame and platform  firmware oriented as it's
> entirely possible for an OEM to have a field firmware upgrade that may enable this
> functionality from the platform and allow an end user to upgrade to a sufficiently
> protected kernel or Windows OS to take advantage of it.

I agree. I will update this in the next version.