INFO: How to fix "Active ring not flushed" xorg fa

[nightm4re]

Well, I've been through a hell of a procedure trying to fix my laptop after I borked it this weekend. I ran it through a standard emerge -uD world (after NEVER doing it on that laptop, EVER). It spent most of the weekend gleefully compiling. After merging all the etc updates (I used dispatch conf and carefully did it, i think..), I go fire up X (6.8.0-r1), and bust open an aterm and WHAM. Whole thing freezes, video gets messed up. So I keep at it, same problem. Then, I try to switch to gnome and start, and it won't even let me into X at all! It borks me out, saying "Active ring not flushed".

BTW, I should mention, the laptop is a Sony Vaio SRX-87, with an Intel 815 chipset (using the xorg i810 driver).

So, I start doing the usual means of trying to fix the problem. I search here, nothing. I pop into #gentoo and #xorg, no one even answers my messages (I tried three times then left, don't want to be rude.)

So, I recompiled xorg, recompiled and upgraded my kernel, still nothing. I downgraded xorg to the version I had before (thanks to rac on #gentoo), still nothing. Now, I'm pissed, cuz I think it's a config problem that I missed.

So then, I search Google, expecting there to be plenty of info. Google returns 29 hits on the string "Active ring not flushed". NOT promising. I start reading a few, and it's basically people who have the same problem I have, with no real solutions (the hits are mostly from mailing lists). I even find the source code of the driver itself and the line it spits the error on. I can't make heads or tails out of it (I know what I'm doing in C++ but not when you're just dumped into one file of a HUGE project, no idea..).

then I find this one post (here it is)

It gives me some things to check into. First of all, I was able to get back i nto X by shutting the machine off and turning it back on again, instead of just rebooting. This seems to "flush" the "active ring".

However, in order to make this fix permanent, I found the culprit. You need to enable MTRR in your kernel (for some reason I didn't have it on, I don't know why). This let me fire up X no problem, run aterm, everything.

Hopefully this will help those who encounter this randomly abstract problem, via Gentoo users or maybe just Google. Happy hunting.