Kernel 5.15.150 black screen with AMD Raven/Picasso GPU

[Greg KH]

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 at gmx.de> wrote:
> > > Am 20.05.24 um 18:22 schrieb Alex Deucher:
> > > 
> > > > On Sat, May 18, 2024 at 8:17 PM Armin Wolf <W_Armin at gmx.de> 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 at lists.freedesktop.org  and amd-gfx at lists.freedesktop.org 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