[Xorg-driver-geode] xf86-video-amd 2.7.7.4 - vm86 vs x86emu

[Martin-Éric Racine]

On 1/5/08, Bart Trojanowski <bart at jukie.net> wrote:
> * Martin-?ric Racine <q-funk at iki.fi> [080105 00:02]:
> >     On products with a General Software BIOS, a freeze occurs while X
> >     is probing VBE.  The same issue occurs with LinuxBIOS and VGAROM,
> >     but not with LinuxBIOS omitting VGAROM.
> >
> >     Both issues appear to be caused by X server core upgrading from
> >     vm86 to x86emu since X server release 1.3, which requires fixing
> >     x86emu, or the concerned BIOSes, or both.
>
> I tested 2.7.7.0, 2.7.7.3 and 2.7.7.4 on ThinCan (General Software BIOS)
> running Ubuntu/Gutsy with xcore 1.3
>
>         - 2.7.7.[03] - GP fault
>         - 2.7.7.[03] w/ patches applied manualy - freeze
>         - 2.7.7.4 - freeze
>
> I also rebuild xcore 1.3 Gutsy package w/ --with-int10=vm86 ...
>
>         - 2.7.7.0 - GP fault
>         - 2.7.7.4 - freeze
>
> We previously thought that going from 1.1 to 1.3 xcore caused this
> because of the change from vm86 to x86emu.  I think this shows that
> x86emu is not at fault.  Martin-Eric said that it could be int10 code.
>
> With vm86 the only difference I see before the freeze is
>
>         (EE) AMD(0): vm86() syscall generated signal 8.
>
> printed on the screen before things top responding.  I don't know if
> that is at all related.

After adding my trivial ztv patch and installing
xserver-xorg-core-dbg, "gdb --args Xorg -configure" gave me this:

8X-----
(==) Log file: "/var/log/Xorg.0.log", Time: Sat Jan  5 20:15:18 2008
[New Thread 0xb7c7d6b0 (LWP 2608)]
List of video drivers:
        amd
        ztv
        fbdev
[tcsetpgrp failed in terminal_inferior: Operation not permitted]
(++) Using config file: "/root/xorg.conf.new"
(II) Module "ddc" already built-in

Program received signal SIGFPE, Arithmetic exception.
[Switching to Thread 0xb7c7d6b0 (LWP 2608)]
8X-----

What is this "[tcsetpgrp failed in terminal_inferior: Operation not
permitted]" supposed to be about? Anything that could cause this
SIGFPE?

-- 
Martin-Éric Racine
http://q-funk.iki.fi