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[47.55.120.4]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8777aabeac7sm224623585a.64.2025.10.02.08.13.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Oct 2025 08:13:08 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1v4KzU-0000000DqDS-0i6h; Thu, 02 Oct 2025 12:13:08 -0300 Date: Thu, 2 Oct 2025 12:13:08 -0300 From: Jason Gunthorpe To: Mostafa Saleh Cc: Will Deacon , linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, robin.murphy@arm.com, jean-philippe@linaro.org, qperret@google.com, tabba@google.com, mark.rutland@arm.com, praan@google.com Subject: Re: [PATCH v4 15/28] iommu/arm-smmu-v3: Load the driver later in KVM mode Message-ID: <20251002151308.GG3195829@ziepe.ca> References: <20250819215156.2494305-1-smostafa@google.com> <20250819215156.2494305-16-smostafa@google.com> <20250923173806.GF2547959@ziepe.ca> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Sep 29, 2025 at 11:10:11AM +0000, Mostafa Saleh wrote: > Another possible solution, to keep a device bound to the KVM driver, > is to probe the SMMUs from the KVM driver, then to create child devices; > possibly use something as device_set_of_node_from_dev to bind those to > the main SMMUv3 or find another way to probe the main SMMUv3 without > changes. I do prefer something more like this one, I think it is nice that the kvm specific driver will remain bound and visible so there is some breadcrumbs about what happened to the system for debugging/etc. Not sure how to do it, but I think it should be achievable.. Maybe even a simple faux/aux device and just pick up the of_node from the parent.. Jason