On Thu, May 23, 2024 at 05:59:39PM +0200, Armin Wolf wrote: > Am 23.05.24 um 15:13 schrieb Barry Kauler: > > > On Wed, May 22, 2024 at 12:58 AM Armin Wolf <W_Armin@xxxxxx> wrote: > > > Am 20.05.24 um 18:22 schrieb Alex Deucher: > > > > > > > On Sat, May 18, 2024 at 8:17 PM Armin Wolf <W_Armin@xxxxxx> wrote: > > > > > Am 17.05.24 um 03:30 schrieb Barry Kauler: > > > > > > > > > > > Armin, Yifan, Prike, > > > > > > I will top-post, so you don't have to scroll down. > > > > > > After identifying the commit that causes black screen with my gpu, I > > > > > > posted the result to you guys, on May 9. > > > > > > It is now May 17 and no reply. > > > > > > OK, I have now created a patch that reverts Yifan's commit, compiled > > > > > > 5.15.158, and my gpu now works. > > > > > > Note, the radeon module is not loaded, so it is not a factor. > > > > > > I'm not a kernel developer. I have identified the culprit and it is up > > > > > > to you guys to fix it, Yifan especially, as you are the person who has > > > > > > created the regression. > > > > > > I will attach my patch. > > > > > > Regards, > > > > > > Barry Kauler > > > > > Hi, > > > > > > > > > > sorry for not responding to your findings. I normally do not work with GPU drivers, > > > > > so i hoped one of the amdgpu developers would handle this. > > > > > > > > > > I CCeddri-devel@xxxxxxxxxxxxxxxxxxxxx and amd-gfx@xxxxxxxxxxxxxxxxxxxxx so that other > > > > > amdgpu developers hear from this issue. > > > > > > > > > > Thanks you for you persistence in finding the offending commit. > > > > Likely this patch should not have been ported to 5.15 in the first > > > > place. The IOMMU requirements have been dropped from the driver for > > > > the last few kernel versions so it is no longer relevant on newer > > > > kernels. > > > > > > > > Alex > > > Barry, can you verify that the latest upstream kernel works on you device? > > > If yes, then the commit itself is ok and just the backporting itself was wrong. > > > > > > Thanks, > > > Armin Wolf > > Armin, > > The unmodified 6.8.1 kernel works ok. > > I presume that patch was applied long before 6.8.1 got released and > > only got backported to 5.15.x recently. > > > > Regards, > > Barry > > > Great to hear, that means we only have to revert commit 56b522f46681 ("drm/amdgpu: init iommu after amdkfd device init") > from the 5.15.y series. > > I CCed the stable mailing list so that they can revert the offending commit. Please submit the patch/revert that you wish to have applied to the tree so we can have the correct information in it. I have no idea what to do here with this deep response thread as-is, sorry. thanks, greg k-h