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Date:   Tue, 22 Jan 2019 12:01:09 +0100
From:   Joerg Roedel <joro@8bytes.org>
To:     Daniel Vetter <daniel@ffwll.ch>
Cc:     Eric Wong <e@80x24.org>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        David Woodhouse <dwmw2@infradead.org>,
        David Airlie <airlied@linux.ie>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        "list@263.net:IOMMU DRIVERS <iommu@lists.linux-foundation.org>, Joerg
        Roedel <joro@8bytes.org>," <iommu@lists.linux-foundation.org>,
        intel-gfx <intel-gfx@lists.freedesktop.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] iommu/intel: quirk to disable DMAR for QM57 igfx
Message-ID: <20190122110109.x3zoynemdl3ysbsn@8bytes.org>
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Hi Daniel,

On Tue, Jan 22, 2019 at 11:46:39AM +0100, Daniel Vetter wrote:
> Note that the string of platforms which have various issues with iommu
> and igfx is very long, thus far we only disabled it where there's no
> workaround to stop it from hanging the box, but otherwise left it
> enabled. So if we make a policy change to also disable it anywhere
> where it doesn't work well (instead of not at all), there's a pile
> more platforms to switch.

I think its best to just disable iommu for the igfx devices on these
platforms. Can you pick up Eric's patch and extend it with the list of
affected platforms?

Thanks,

	Joerg