Bill Crawford reports in both bug #20816 and bug #18160 that the cards are not being POSTed properly. This bug is for discussion of that issue.
The relevant discussion from bug #20816 is as follows:
------- Comment #2 From Bill Crawford 2009-03-24 05:03:34 PST [reply] -------
It's looking as though POSTing still isn't working correctly on some systems
(notably mine :o)).
With the older X server (Xorg 1.3 on Fedora 8), it works. Each card comes up in
turn, and it looks as though the other two cards are briefly disabled as each
POSTs (they turn black). With latest X server in Fedora Rawhide (which is
labelled as "1.6.0"), that doesn't happen, and I see random characters appear
on the primary screen when the second is POSTing; when display appears, second
screen is completely garbled, looking like an "encrypted" satellite or cable
channel, I'll try to take a photo some time but my phone doesn't have a very
What is the older X server doing differently? I've had a quick look at the
sources for the int10 module and BIOS-reading, but it's not immediately obvious
whether anything is wrong there; I'll look at the ATI driver source when I have
a little more time.
------- Comment #3 From Pedro Eugênio Rocha 2009-03-24 07:07:49 PST [reply] -------
I compared the instructions that x86emu executes in both Xorg versions, 1.4.2
and 1.6.99. I realized that in the newer Xorg all the instructions returns 0,
differently from the older Xorg. It seems that x86emu was reading or writing in
the wrong memory location. As all the operations return 0, the loop in
'hw/xfree/x86emu/decode.c' function 'X86EMU_exec' never exits, hanging the
system. I compiled both Xorgs using x86emu int10 backend. On my system, the
BIOS is being read correctly. Sorry if I said something that you already know.
I'm using a sis and ati video card.
Pedro, this sounds like it could be my current problem. I'm in pretty much the same situation as Bill Crawford (ie. used to work, doesn't now), except one screen never activates, and the other gets stuck at the "black and white dots pattern" stage. Examining the Xorg.0.log shows that everything which is supposed to have happened there did, but the screens get stuck and produce no useful output, and I can't get the console to respond in any way, although I can still SSH in.
Did you get a chance to try to fix this problem?
I don't know if my problem is the same as yours. My secondary video card is never activated, hanging the system when it tries to use int10 to initialize it.
I've started to work with this bug a week ago, so I'm not pretty sure of where exactly is the bug. I'm trying to isolate the problem, and I get to the bug that I described before. It seems that x86emu is trying to read the wrong memory address, or is writing in the wrong place, because the operations always return 0, despite the older version.
I really don't know if I'll find the problem, but I'll still trying. Any help would be apreciated.
Pedro, have you looked at the stuff in bug #18160 to see if any of that is relevant to you? If your Xorg still has the last line saying something like "Initialising int10", then you probably haven't resolved the stuff in bug #18160. To test this, echo "1" into /sys/bus/pci/devices/<device-id>/enable in which, of course, you'll need to substitute the correct device-id (which you can get with lspci).
Bill, are you still getting "Initialising int10" as the last line in your Xorg when the thing locks up?
Mass closure: This bug has been untouched for more than six years, and is not obviously still valid. Please file a new report if you continue to experience issues with a current server.