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Fri, 19 Sep 2025 04:58:07 -0700 (PDT) Received: from ziepe.ca ([130.41.10.202]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8363198ad41sm325729185a.46.2025.09.19.04.58.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Sep 2025 04:58:06 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1uzZkb-000000097c5-40qZ; Fri, 19 Sep 2025 08:58:05 -0300 Date: Fri, 19 Sep 2025 08:58:05 -0300 From: Jason Gunthorpe To: "Tian, Kevin" Cc: Keith Busch , Alex Mastro , Alex Williamson , Bjorn Helgaas , David Reiss , Joerg Roedel , Leon Romanovsky , Li Zhe , Mahmoud Adam , Philipp Stanner , Robin Murphy , "Kasireddy, Vivek" , Will Deacon , Yunxiang Li , "linux-kernel@vger.kernel.org" , "iommu@lists.linux.dev" , "kvm@vger.kernel.org" Subject: Re: [TECH TOPIC] vfio, iommufd: Enabling user space drivers to vend more granular access to client processes Message-ID: <20250919115805.GU1326709@ziepe.ca> References: <20250918214425.2677057-1-amastro@fb.com> <20250918225739.GS1326709@ziepe.ca> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Sep 19, 2025 at 07:00:04AM +0000, Tian, Kevin wrote: > memory of other clients and the USD... there is no hw isolation > within a partitioned IOAS unless the device supports PASID then > each client can be associated to its own IOAS space. If the device does support pasid then both of the suggestions make a lot more security sense.. Jsaon