Amdgpu errors and failing to power off

I have a new (second hand) HP zbook 15u G5, which has an AMD Radeon Pro WX 3100 GPU (and an integrated Intel UHD Graphics 630).

After install, when shutting down the laptop, it appears to reach the end of the shutdown process but does not power off. The last lines displayed in the shutdown process are

powering off
kvm: exiting hardware virtualisation

at which point the machine hangs.

Looking through the Journald log, I see

these errors occurring at startup

kernel	x86/cpu: SGX disabled by BIOS.
kernel	ACPI BIOS Error (bug): AE_AML_BUFFER_LIMIT, Field [CAP1] at bit offset/length 64/32 exceeds size of target Buffer (64 bits) (20210730/dsopcode-198)
kernel	ACPI Error: Aborting method \_SB._OSC due to previous error (AE_AML_BUFFER_LIMIT) (20210730/psparse-529)
kernel	snd_hda_codec_conexant hdaudioC0D0: vmaster hook already present before cdev!
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu: Voltage value looks like a Leakage ID but it's not patched 
kernel	amdgpu 0000:01:00.0: [drm:amdgpu_ring_test_helper [amdgpu]] *ERROR* ring uvd test failed (-110)
kernel	[drm:amdgpu_device_init.cold [amdgpu]] *ERROR* hw_init of IP block <uvd_v6_0> failed -110
kernel	amdgpu 0000:01:00.0: amdgpu: amdgpu_device_ip_init failed
kernel	amdgpu 0000:01:00.0: amdgpu: Fatal error during GPU init
kernel	amdgpu 0000:01:00.0: [drm:amdgpu_ring_test_helper [amdgpu]] *ERROR* ring kiq_2.1.0 test failed (-110)
kernel	[drm:gfx_v8_0_hw_fini [amdgpu]] *ERROR* KCQ disable failed
kernel	amdgpu: cp is busy, skip halt cp
kernel	Bluetooth: hci0: Reading supported features failed (-16)
kernel	amdgpu: rlc is busy, skip halt rlc
systemd-udevd	0000:01:00.0: Worker [295] failed
kernel	BUG: unable to handle page fault for address: ffffa76340154000
kernel	#PF: supervisor read access in kernel mode
kernel	#PF: error_code(0x0000) - not-present page
systemd	Failed to start Update XDG user dir configuration.

and these errors occurring at shutdown

pulseaudio	Error opening PCM device front:0: No such file or directory
pulseaudio	Error opening PCM device front:0: No such file or directory
systemd-logind	Failed to start autovt@tty2.service: Transaction for getty@tty2.service/start is destructive (systemd-poweroff.service has 'start' job queued, but 'stop' is included in transaction).

So, nothing sticks out to me as obviously the cause of the shutdown problem, but kernel BUG: unable to handle page fault for address seems worrying and I wonder whether it could be related to the amdgpu errors, so I thought 'd start by looking at those.

Looking for some more information about my graphics configuration:

> lcpi
…
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07)
…
01:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Lexa XT [Radeon PRO WX 3100]
…
> xrandr --listproviders
Providers: number : 0
> glxinfo | grep "OpenGL renderer" 
OpenGL renderer string: Mesa Intel(R) UHD Graphics 620 (KBL GT2)
> DRI_PRIME=1 glxinfo | grep "OpenGL renderer"                                                   ✔ 
OpenGL renderer string: Mesa Intel(R) UHD Graphics 620 (KBL GT2)


> xrandr --setprovideroffloadsink radeon Intel                                                   ✔
Could not find provider with name radeon

The manjaro hardware configuration tool shows:

                                                     open-source  installed
display controller
|
|--Lexa XT [Radeon PRO WX 3100] (ATI Technologies Inc)   
|       |---------------------------------video-linux     ✅         ✅ 
|
|-- UHD Graphics 620 (Intel Corporation)
        |---------------------------------video-linux     ✅         ✅ 
        |-------------------------------video-modesetting ✅         □     
        |---------------------------------video-vesa      ✅         □

A bit more backstory:
I first attempted to use the regular Arch iso to install (which has been my regular distro) but I couldn’t get it to boot. I then tried the Archlinux GUI installer (which I realised later appears to use the Manjaro installer tool). This installed, but had the same issue that I am now experiencing with Manjaro. On the Arch GUI installed syste, I hibernated the laptop, after which I was unable to get back to a usable system - at SDDM I would have a movable cursor but everything else was frozen and I was unable to switch virtual terminals with ctrl-alt-Fx.

Since I have been interested in trying Manjaro for a while and I heard that the Manjaro installer does a good job of hardware detection and configuration, I thought I’d give it a go.

p.s. All help very gratefully received. I intentionally avoided the option of switchable NVIDIA graphics, with which I have had a headache in the past (years ago) and went for this because I heard that amd gpu configuration was easier and more reliable.

Updated with more errors from the journald log