https://bugs.freedesktop.org/show_bug.cgi?id=56878
--- Comment #5 from Alex Deucher agd5f@yahoo.com --- (In reply to comment #4)
If I read dmesg correctly, it defaults to agp mode 2 but the bug still appears with radeon.agpmode=1. Using radeon.agpmode=-1 avoids the freeze, though. agpmode=-1 will be slower than the default, won't it? Anything else I can do to help with fixing this bug?
does agpmode=4 or 8 help? agpmode=-1 may be slower, depends on the system and what you are doing. AGP is old and was kind of broken by design so I don't think anyone is going to put much effort into making it work better at this point.