Comment 5 for bug 1863385

I also have a 3400G with a freezing bug. Two questions to help establish whether it's the same bug:

> The system has been crashing (no response to mouse/keyboard, but the screen seems to still be updating).

When you say the screen is updating, what exactly do you mean, please? My bug means the screen blanks to black, then returns to where it was (or an earlier frame), and the mouse cursor moves. But actually, it's a graphics crash: Clicking on buttons etc. has no effect and if I use the keyboard to open a Terminal (Ctrl+Alt+T) and reboot, I get a response about half the time. This is consistent with what I see in the SysLog, which reports a series of amdgpu crashes and failed resets.

> I see a lot of junk in dmesg about amdgpu.

Are you seeing messages like these or something different, please?:

[drm:amdgpu_dm_commit_planes.constprop.0 [amdgpu]] *ERROR* Waiting for fences timed out!
Apr 5 01:12:11 paul kernel: [ 285.638026] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring gfx timeout, signaled seq=92956, emitted seq=92958
Apr 5 01:12:11 paul kernel: [ 285.638075] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* Process information: process RLTM3.exe pid 3670 thread RLTM3.exe:cs0 pid 3700
Apr 5 01:12:11 paul kernel: [ 285.638078] amdgpu 0000:27:00.0: amdgpu: GPU reset begin!

It might help you to know that many people with amdgpu bugs in Ryzen report that setting the kernel parameter iommu=pt fixes them, though this does not help me.