From mboxrd@z Thu Jan  1 00:00:00 1970
From: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Subject: Re: [RFC PATCH v5 02/11] ARM SMMU: Add capability IOMMU_CAP_DMA_EXEC
Date: Mon, 28 Apr 2014 20:37:10 +0100
Message-ID: <20140428193709.GE22135@arm.com>
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To: Antonios Motakis <a.motakis-lrHrjnjw1UfHK3s98zE1ajGjJy/sRE9J@public.gmane.org>
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On Mon, Apr 28, 2014 at 04:52:42PM +0100, Antonios Motakis wrote:
> The ARM SMMU can take an IOMMU_EXEC protection flag in addition to
> IOMMU_READ and IOMMU_WRITE. Expose this as an IOMMU capability.

The other way of handling this would be to negate the capability and
advertise a NOEXEC cap instead. That would need the IOMMU_EXEC flag to
become IOMMU_NOEXEC and the ARM SMMU driver updating accordingly, but it
might make more sense if people don't object to mixing positive and negative
logic in the IOMMU_* flags.

Any thoughts?

Will