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Subject: Re: [PATCH v2 19/24] iommu: Expose DMA domain strictness via sysfs
To:     Robin Murphy <robin.murphy@arm.com>, <joro@8bytes.org>,
        <will@kernel.org>
CC:     <iommu@lists.linux-foundation.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <suravee.suthikulpanit@amd.com>,
        <baolu.lu@linux.intel.com>, <dianders@chromium.org>
References: <cover.1627468308.git.robin.murphy@arm.com>
 <dd26592103c7613ef9fdff703d0d2ed2df8305c2.1627468310.git.robin.murphy@arm.com>
From:   John Garry <john.garry@huawei.com>
Message-ID: <5078e29c-029c-8bab-613f-46c94507c64d@huawei.com>
Date:   Fri, 30 Jul 2021 11:20:42 +0100
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On 28/07/2021 16:58, Robin Murphy wrote:
> The sysfs interface for default domain types exists primarily so users
> can choose the performance/security tradeoff relevant to their own
> workload. As such, the choice between the policies for DMA domains fits
> perfectly as an additional point on that scale - downgrading a
> particular device from a strict default to non-strict may be enough to
> let it reach the desired level of performance, while still retaining
> more peace of mind than with a wide-open identity domain. Now that we've
> abstracted non-strict mode as a distinct type of DMA domain, allow it to
> be chosen through the user interface as well.
> 
> Signed-off-by: Robin Murphy<robin.murphy@arm.com>
> ---

Reviewed-by: John Garry <john.garry@huawei.com>