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See http://www.infradead.org/rpr.html Cc: intel-gfx@lists.freedesktop.org, Joonas Lahtinen , linux-kernel@vger.kernel.org, Jani Nikula , iommu@lists.linux-foundation.org, Rodrigo Vivi , David Woodhouse X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Thu, Sep 03, 2020 at 09:18:37PM +0100, Tom Murphy wrote: > Disable combining sg segments in the dma-iommu api. > Combining the sg segments exposes a bug in the intel i915 driver which > causes visual artifacts and the screen to freeze. This is most likely > because of how the i915 handles the returned list. It probably doesn't > respect the returned value specifying the number of elements in the list > and instead depends on the previous behaviour of the intel iommu driver > which would return the same number of elements in the output list as in > the input list. So what is the state of addressing this properly in i915? IF we can't get it done ASAP I wonder if we need a runtime quirk to disable merging instead of blocking this conversion.. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu