OS: OpenSUSE tumbleweed x86_64 updated (2018 04 21)
Kernel: 4.16.2-1-default
Desktop Environment: KDE Plasma (x11)
OpenGL version string: 3.0 Mesa 18.0.0
GPU: AMD Radeon RX Vega 64 8GB

Symptoms:
During gaming sessions, system locks up and freezes completely. Audio seems to
keep working for a few seconds more, but full desktop is frozen, no mouse and
keyboard actions available. Hard reset only possible action on local pc. I have
not tried to ssh in the PC from another box.
I noticed this on both games running through wine, and native games via steam.
Some times I can play for 20 minutes, some times for a few hours. Freezes seem
unrelated to any activity running in-game. All system temperatures are under
control.
The system outside of 3d gaming is very stable, including playing videos,
encoding videos, regular desktop usage.

I am trying to gather more logs. This is what I have for now:

System Logs:

Apr 21 17:08:34 STUDIO kernel: [drm:gfx_v9_0_priv_reg_irq [amdgpu]] *ERROR*
Illegal register access in command stream
Apr 21 17:08:34 STUDIO kernel: [drm] No hardware hang detected. Did some blocks
stall?
Apr 21 17:08:44 STUDIO kernel: [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring
gfx timeout, last signaled seq=128859, last emitted seq=128861
Apr 21 17:08:44 STUDIO kernel: [drm] No hardware hang detected. Did some blocks
stall?
-- Reboot --


Dmesg lines relative to amdgpu:

[    3.407020] [drm] amdgpu kernel modesetting enabled.
[    3.411462] fb: switching to amdgpudrmfb from VESA VGA
[    3.426163] amdgpu 0000:04:00.0: Invalid PCI ROM header signature: expecting
0xaa55, got 0xffff
[    3.426261] amdgpu 0000:04:00.0: VRAM: 8176M 0x000000F400000000 -
0x000000F5FEFFFFFF (8176M used)
[    3.426263] amdgpu 0000:04:00.0: GTT: 256M 0x000000F600000000 -
0x000000F60FFFFFFF
[    3.426371] [drm] amdgpu: 8176M of VRAM memory ready
[    3.426372] [drm] amdgpu: 8176M of GTT memory ready.
[    4.031665] fbcon: amdgpudrmfb (fb0) is primary device
[    4.083803] amdgpu 0000:04:00.0: fb0: amdgpudrmfb frame buffer device
[    4.096086] amdgpu 0000:04:00.0: ring 0(gfx) uses VM inv eng 4 on hub 0
[    4.096088] amdgpu 0000:04:00.0: ring 1(comp_1.0.0) uses VM inv eng 5 on hub
0
[    4.096089] amdgpu 0000:04:00.0: ring 2(comp_1.1.0) uses VM inv eng 6 on hub
0
[    4.096090] amdgpu 0000:04:00.0: ring 3(comp_1.2.0) uses VM inv eng 7 on hub
0
[    4.096091] amdgpu 0000:04:00.0: ring 4(comp_1.3.0) uses VM inv eng 8 on hub
0
[    4.096093] amdgpu 0000:04:00.0: ring 5(comp_1.0.1) uses VM inv eng 9 on hub
0
[    4.096094] amdgpu 0000:04:00.0: ring 6(comp_1.1.1) uses VM inv eng 10 on
hub 0
[    4.096095] amdgpu 0000:04:00.0: ring 7(comp_1.2.1) uses VM inv eng 11 on
hub 0
[    4.096096] amdgpu 0000:04:00.0: ring 8(comp_1.3.1) uses VM inv eng 12 on
hub 0
[    4.096098] amdgpu 0000:04:00.0: ring 9(kiq_2.1.0) uses VM inv eng 13 on hub
0
[    4.096099] amdgpu 0000:04:00.0: ring 10(sdma0) uses VM inv eng 4 on hub 1
[    4.096100] amdgpu 0000:04:00.0: ring 11(sdma1) uses VM inv eng 5 on hub 1
[    4.096101] amdgpu 0000:04:00.0: ring 12(uvd) uses VM inv eng 6 on hub 1
[    4.096103] amdgpu 0000:04:00.0: ring 13(uvd_enc0) uses VM inv eng 7 on hub
1
[    4.096104] amdgpu 0000:04:00.0: ring 14(uvd_enc1) uses VM inv eng 8 on hub
1
[    4.096105] amdgpu 0000:04:00.0: ring 15(vce0) uses VM inv eng 9 on hub 1
[    4.096107] amdgpu 0000:04:00.0: ring 16(vce1) uses VM inv eng 10 on hub 1
[    4.096108] amdgpu 0000:04:00.0: ring 17(vce2) uses VM inv eng 11 on hub 1
[    4.096662] [drm] Initialized amdgpu 3.23.0 20150101 for 0000:04:00.0 on
minor 0