Hi everyone, I'm new to the forums and found this thread. I also have reset issues with both my rx 580 and vega 64. I did find this on the level one forum:
https://forum.level1techs.com/t/solved-testers-needed-pci-passthrough-with-4-19rcx-pci-reset-regression/132372
Looks like there is a fix with kernel 4.19. I haven't tested myself as my only system is my Unraid box, which is sporting the 6.6.0-rc4 which is awesome btw. It's currently on kernel 4.18 but I'm hoping they add this patch or move to kernel 4.19 when it's stable. Hope it's soon :).