I'd like to report a finding on
my Satellite 1110-z16 with
Mobile Celeron 1500 and Radeon LY under SuSE 8.1
and Mandrake 9
using the installed XFree86-4.2 based X11/Mesa.
Both show a problem with many 3D Linux apps
arborting with SIGILL,
MESA_DEBUG showed that the apps were thinking that the
supported 3DNow(message 3dnow supported was printed) which it
least does not when checking /proc/cpuinfo.
After I disabled the use of 3dnow by exporting
everything works but it's a not good needing to export it and
only a workaround.
So it looks like as if the Mesa CPUID asm gets the
bit set, so the feature is enabled and depending what the app
it gets the sigill or not(glxgears and fgfs do not but show
rendering in a part of the window if I move another window into
middle of the 3d window.
Both distributions use Free 4.2 code, but I've
downloading the 4.3.99 rpms do test with it.
Just guessing(maybe fixed already, just could not
get the newest
XF86 4.3/Mesa Source over the slow modem I'm using atm yet,
working on it):
I've checked the 2.4.19 x86 feature/CPUID code
arch/i386/kernel/setup.c and found a place where it
does something to
the 3dnow flag.
Maybe the CPUID regs set on stepping 7 of the
Celeron 1500 are a bit different and the kernel handles
this by the
special 3dnow lines I've seen.