From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Drake Subject: Re: amd-iommu: can't boot with amdgpu, AMD-Vi: Completion-Wait loop timed out Date: Fri, 17 Mar 2017 06:15:58 -0600 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Deucher, Alexander" Cc: Chris Chiu , "amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org" , "Nath, Arindam" , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , Linux Upstreaming Team List-Id: iommu@lists.linux-foundation.org Hi, On Mon, Mar 13, 2017 at 2:01 PM, Deucher, Alexander wrote: > > We are unable to boot Acer Aspire E5-553G (AMD FX-9800P RADEON R7) nor > > Acer Aspire E5-523 with standard configurations because during boot > > the screen is flooded with the following error message over and over: > > > > AMD-Vi: Completion-Wait loop timed out > > We ran into similar issues and bisected it to commit b1516a14657acf81a587e9a6e733a881625eee53. I'm not too familiar with the IOMMU hardware to know if this is an iommu or display driver issue yet. We can confirm that reverting this commit solves the issue. Given that that commit is an optimization, but it has introduced a regression on multiple platforms, and has been like this for 8 months, it would be common practice to now revert this patch upstream until the regression is fixed. Could you please send a new patch to do this? Also, we would be happy to test any real solutions to this issue while we still have the affected units in hand. Thanks Daniel