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[47.54.130.67]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8f7c87acaacsm247411785a.43.2026.04.28.10.44.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Apr 2026 10:44:04 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1wHmTb-0000000C6wg-3fSo; Tue, 28 Apr 2026 14:44:03 -0300 Date: Tue, 28 Apr 2026 14:44:03 -0300 From: Jason Gunthorpe To: Easwar Hariharan Cc: Joonwon Kang , will@kernel.org, robin.murphy@arm.com, joro@8bytes.org, jpb@kernel.org, nicolinc@nvidia.com, praan@google.com, kees@kernel.org, amhetre@nvidia.com, Alexander.Grest@microsoft.com, baolu.lu@linux.intel.com, smostafa@google.com, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC] iommu: Enable per-device SSID space for SVA Message-ID: <20260428174403.GK849557@ziepe.ca> References: <20260424085339.3503582-1-joonwonkang@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260428_104407_081544_DF38785A X-CRM114-Status: UNSURE ( 9.51 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Apr 28, 2026 at 10:38:37AM -0700, Easwar Hariharan wrote: > process address space, and would break the DSA<->IAA kind of interaction where the > device drivers can communicate the PASID among each other to operate on the same > process address space. That is not part of the Linux model... Each device has to get its own SVA and it must use the returned PASID, not just invent one from someplace else. Jason