Comment # 13 on bug 109955 from Mauro Gaspari

Status update: I updated the BIOS and now disabled all kernel parameters I
previously used. It might take some time to make sure the system is stable. 

Regarding your frustrations,
AMD released open source drivers and that is a major improvement for people on
Linux. I got the Vega RX64 to support that. I expected a few bumps in the road
but well, it is taking longer than anticipated.

Having said that, there you are all kernel parameters I enabled, and with those
as I said, I was unable to get a single freeze. Those are not fixes, most
likely optimizations and workarounds. Still, work pretty well for me.

CPU
rcu_nocbs=0-15 (adjust to the number of cores of your cpu)
idle=nomwait
processor.max_cstate=5
pcie_aspm=off 

GPU
amdgpu.dc=1
amdgpu.vm_update_mode=0
amdgpu.dpm=-1
amdgpu.ppfeaturemask=0xffffffff
amdgpu.vm_fault_stop=2
amdgpu.vm_debug=1
amdgpu.gpu_recovery=0