Created attachment 842226 [details]
/var/log/messages

On updating to kernel 5.3.18-lp152.41-default or 5.3.18-lp152.44-default (from
kernel 5.3.18-lp152.36-default) I experienced a `freeze' during system boot-up.
Using debug mode, the last message was:

Fb0: switching to amdgpudrmfb from EFI VGA

Something seems to be going from when switching graphics mode. Adding
'nomodeset' to the kernel option allows the boot to go to completion, at the
cost of not having an accelerated graphics driver!


The problem is perhaps the same as described on
https://forum.level1techs.comhttps://forum.level1techs.com/t/fb0-switching-to-amdgpudrmfb-from-efi-vga/152112
, some sort of problem with MMU and ATS?

I am currently booting on the previous kernel version (5.3.18-lp152.36-default)
without any difficulty

My hardware:
Asrock B550M
AMD Ryzen 5 3600
AMD RX 570 graphics card (MSI) - amdgpu-pro driver 

Attached is what appears to be the relevant section of /var/log/messages

2020-10-03T16:11:09.966215+10:00 localhost kernel: [    3.851924] mc: Failed to
load firmware "amdgpu/polaris10_mc.bin"
2020-10-03T16:11:09.966216+10:00 localhost kernel: [    3.851963]
[drm:gmc_v8_0_sw_init [amdgpu]] *ERROR* Failed to load mc firmware!
2020-10-03T16:11:09.966217+10:00 localhost kernel: [    3.851998]
[drm:amdgpu_device_init [amdgpu]] *ERROR* sw_init of IP block <gmc_v8_0> failed
-2
2020-10-03T16:11:09.966217+10:00 localhost kernel: [    3.852000] amdgpu
0000:0c:00.0: amdgpu_device_ip_init failed
2020-10-03T16:11:09.966218+10:00 localhost kernel: [    3.852002] amdgpu
0000:0c:00.0: Fatal error during GPU init
2020-10-03T16:11:09.966218+10:00 localhost kernel: [    3.852003] [drm] amdgpu:
finishing device.