I suffered the reset bug as well.
If you get the error:
Error: unknown pci header type ‘127’
I happened to stuble upon a workaround on the forum here:
https://forum.level1techs.com/t/attention-amd-vfio-users-do-not-update-your-bios/142685
Basically it boils down to applying a patch on the kernel:
https://clbin.com/VCiYJ
Hope this helps 