Red Hat Bugzilla – Bug 173710
x server built with wrong cpu options?
Last modified: 2007-11-30 17:11:17 EST
Trying to run the new modular bits on my VIA box, which doesn't support cmov,
results in the following at the end of my log (a SIGILL). It looks like one
of the X packages is built with an i686 compile option or something?
(II) Initializing built-in extension RANDR
(II) Initializing built-in extension COMPOSITE
(II) Initializing built-in extension DAMAGE
(II) Initializing built-in extension XEVIE
*** If unresolved symbols were reported above, they might not
*** be the reason for the server aborting.
Fatal server error:
Caught signal 4. Server aborting
Everything is built with the stock $RPM_OPT_FLAGS, passed through via rpm.
Install the debuginfo packages, enable core dumps, and enable NoTrapSignals
in the serverflags section of xorg.conf, then run the X server as root and
get a core dump if possible.
Alternatively, run gdb on the server (from another computer) to try to
trace what's going wrong.
Hope this helps.
I just confirmed that we our default compiler flags do not use CMOV, and
should work fine on via CPUs. The only other code in the X server that I
can think of which could theoretically trigger a SIGILL, is the MMX/SSE
code used in fbmmx et al.
I'd recommend reporting this bug to X.Org bugzilla, and attaching your X
server log and config file to the upstream bug report, then pasting the
URL here for us to track. If there is a problem in the MMX/SSE code, it
will affect all distributions.
Yep, that looks like the problem:
Program received signal SIGILL, Illegal instruction.
0x00dd4c16 in fbHaveMMX () from /usr/lib/xorg/modules/libfb.so
I'll report it upstream.
What's the upstream bug URL?
Upstream url is https://bugs.freedesktop.org/show_bug.cgi?id=5093. Patch in
that bug fixes this problem.
Fixed in xorg-x11-server-utils-0.99.2-7:
* Wed Nov 23 2005 Mike A. Harris <firstname.lastname@example.org> 0.99.2-7
- Update xorg-x11-server-utils dep to 0.99.2-5 to ensure rgb.txt is installed
in correct location - _datadir/X11/rgb
- Added --with-rgb-path configure option to specify _datadir/X11/rgb so the
X server finds the rgb.txt database properly, for bugs (#173453, 173435,
173428, 173483, 173734, 173737, 173594)
- Added xorg-server-0.99.3-fbmmx-fix-for-non-SSE-cpu.patch to prevent SSE/MMX
code from being activated on non-capable VIA CPU. (#173384,fdo#5093)