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Date:   Tue, 31 Aug 2021 17:39:35 -0400
From:   Alyssa Rosenzweig <alyssa@rosenzweig.io>
To:     Sven Peter <sven@svenpeter.dev>
Cc:     iommu@lists.linux-foundation.org, Joerg Roedel <joro@8bytes.org>,
        Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Arnd Bergmann <arnd@kernel.org>,
        Mohamed Mediouni <mohamed.mediouni@caramail.com>,
        Alexander Graf <graf@amazon.com>,
        Hector Martin <marcan@marcan.st>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 6/8] iommu: Move IOMMU pagesize check to attach_device
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References: <20210828153642.19396-1-sven@svenpeter.dev>
 <20210828153642.19396-7-sven@svenpeter.dev>
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> +	if ((1 << __ffs(domain->pgsize_bitmap)) > PAGE_SIZE) {

Not a fan of this construction. Could you assign `(1 <<
__ffs(domain->pgsize_bitmap))` to an appropriately named temporary (e.g
min_io_pgsize) so it's clearer what's going on?

> +		pr_warn("IOMMU page size cannot represent CPU pages.\n");

"Represent" how?