I reported this on the Mesa tracker but no progress has been done in 3 months.
I have been using D9VK to play The Witcher 2 (also tested with Wine's and it also occurred) and I have found that once in a while my entire system freezes and hangs. I cannot enter TTY and I believe this is a gfx ring issue.
Unfortunately I cannot replicate the issue when doing an apitrace. I really did try playing with 10fps for hours and hours (longer than it normally would have taken for it to hang) but I cannot seem to get it. Instead I gathered these two files dmesg log and the RADV_TRACE_FILE log in hope it can help.
sudo journalctl -b -1 > dmesg.log
RADV_TRACE_FILE=$HOME/trace steam &> hang.report
Mesa 20.1.0-devel (git-7086b38c81)
Options in etc environment:
Link to original report: The Witcher 2 unpredicably hangs Navi system (#2369) · Issues · Mesa / mesa · GitLab