Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756831AbaD1ThP (ORCPT ); Mon, 28 Apr 2014 15:37:15 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:40796 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751690AbaD1ThN (ORCPT ); Mon, 28 Apr 2014 15:37:13 -0400 Date: Mon, 28 Apr 2014 20:37:10 +0100 From: Will Deacon To: Antonios Motakis Cc: "alex.williamson@redhat.com" , "kvmarm@lists.cs.columbia.edu" , "iommu@lists.linux-foundation.org" , "tech@virtualopensystems.com" , "a.rigo@virtualopensystems.com" , "kvm@vger.kernel.org" , "christoffer.dall@linaro.org" , "kim.phillips@freescale.com" , "stuart.yoder@freescale.com" , Joerg Roedel , Varun Sethi , Alexey Kardashevskiy , Shuah Khan , "Upinder Malhi (umalhi)" , "moderated list:ARM SMMU DRIVER" , open list Subject: Re: [RFC PATCH v5 02/11] ARM SMMU: Add capability IOMMU_CAP_DMA_EXEC Message-ID: <20140428193709.GE22135@arm.com> References: <1398700371-20096-1-git-send-email-a.motakis@virtualopensystems.com> <1398700371-20096-3-git-send-email-a.motakis@virtualopensystems.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1398700371-20096-3-git-send-email-a.motakis@virtualopensystems.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/