Created attachment 139474 [details]
dmesg

Reproduce:

1) boot
2) Start X
3) Stop X
4) cat /sys/kernel/debug/dri/2/amdgpu_gpu_recovery
5) Wait till finished
6) Start X
7) Notice slowness
8) Stop X

The dmesg says that the reset failed, but the screen comes back with some
artifacts. drawing in X is very slow event though pp_dpm_sclk seems to be
indicating reasonable speeds.

I use amd-staging-drm-next as of today with as last commit

commit 905aa01b240f9216b6dbba3226bf10b2d96eebb7 (origin/amd-staging-drm-next)
Author: Colin Ian King <colin.king@canonical.com>
Date:   Wed May 2 15:43:16 2018 +0100

    drm/amd/display: clean up assignment of amdgpu_crtc

    The declaration of pointer amdgpu_crtc has a redundant assignment to
    amdgpu_crtc. Clean this up by removing it.

    Detected by CoverityScan, CID#1460299 ("Evaluation order violation")

    Reviewed-by: Harry Wentland <harry.wentland@amd.com>
    Signed-off-by: Colin Ian King <colin.king@canonical.com>
    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>


plus a patch of my own adding some more dev_info messages to the reset process.