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Date:   Wed, 28 Jun 2023 12:43:25 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Nicolin Chen <nicolinc@nvidia.com>, will@kernel.org,
        joro@8bytes.org, shameerali.kolothum.thodi@huawei.com,
        yangyicong@hisilicon.com, jean-philippe@linaro.org,
        linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1] iommu/arm-smmu-v3: Allow default substream bypass
 with a pasid support
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On Wed, Jun 28, 2023 at 04:39:48PM +0100, Robin Murphy wrote:

> > I'd try keeping most of the parts intact while adding a pointer
> > to a structure holding pagetable stuff, to make it cleaner. Then
> > the S1DSS bypass case can be flagged by an empty pointer.
> 
> I'd expect that what you need for this is much the same as what Michael has
> already proposed for the PASID-generalisation series. The current inside-out
> notion of S1 domains owning CD tables is what's getting in the way of doing
> the right thing cleanly, in both cases.

Yeah, that was sort of my guessed feeling as well..

What do you think of Michael's series?

Jason