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Date:   Tue, 6 Jul 2021 16:05:13 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Will Deacon <will@kernel.org>, Christoph Hellwig <hch@lst.de>,
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Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for
 swiotlb data bouncing
Message-ID: <20210706140513.GA26498@lst.de>
References: <YNyUQwiagNeZ9YeJ@Ryzen-9-3900X.localdomain> <20210701074045.GA9436@willie-the-truck> <ea28db1f-846e-4f0a-4f13-beb67e66bbca@kernel.org> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> <YN/7xcxt/XGAKceZ@Ryzen-9-3900X.localdomain> <20210705190352.GA19461@willie-the-truck> <20210706044848.GA13640@lst.de> <20210706132422.GA20327@willie-the-truck> <a59f771f-3289-62f0-ca50-8f3675d9b166@arm.com>
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On Tue, Jul 06, 2021 at 03:01:04PM +0100, Robin Murphy wrote:
> FWIW I was pondering the question of whether to do something along those 
> lines or just scrap the default assignment entirely, so since I hadn't got 
> round to saying that I've gone ahead and hacked up the alternative 
> (similarly untested) for comparison :)
>
> TBH I'm still not sure which one I prefer...

Claire did implement something like your suggestion originally, but
I don't really like it as it doesn't scale for adding multiple global
pools, e.g. for the 64-bit addressable one for the various encrypted
secure guest schemes.