Created attachment 26906 [details]
xorg.conf

System Environment:
--------------------------
Libdrm:		(master)3d4bfe8c893d016ef43d1ebf28e4607aa1f540a4
Mesa:		(mesa_7_5_branch)fb64365642be82ac0dc0d43452afc4650d309b53
Xserver:	(server-1.6-branch)6be19e8f43086fb4b7fb30a47b89b5f3eed798ef
Xf86_video_intel:	(master)cdbf84f20295c8a78624318aa6fdfff3f5c8ce27
Kernel:       (for-airlied)0e7ddf7eeeef5aea85412120539ab5369577faeb

Bug detailed description:
-------------------------
With the new code, texturing/texrect-many.c will have a segment fault now. I find it is caused by xserver, it works well with db61eff891675aeaf2466c3529424de4621005dc failed with 6be19e8f43086fb4b7fb30a47b89b5f3eed798ef. I will bisect it. And I found general/texgen.c has a segment fault too. 
It has the following debug info: 
Starting program: /GFX/Test/Piglit/piglit/bin/texrect-many
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 0x7ffff6090750 (LWP 2479)]

Program received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()
Missing separate debuginfos, use: debuginfo-install e2fsprogs-libs-1.41.3-2.fc10.x86_64 expat-2.0.1-5.x86_64 glibc-2.9-3.x86_64
libICE-1.0.4-4.fc10.x86_64 libSM-1.1.0-2.fc10.x86_64 libXdamage-1.1.1-4.fc9.x86_64 libXdmcp-1.0.2-6.fc10.x86_64 libXfixes-4.0.3-4.fc10.x86_64 libXi-1.1.3-4.fc9.x86_64 libXmu-1.0.4-1.fc9.x86_64 libXt-1.0.5-1.fc10.x86_64 libXxf86vm-1.0.2-1.fc10.x86_64 libgcc-4.3.2-7.x86_64 libjpeg-6b-43.fc10.x86_64 libpng-1.2.35-1.fc10.x86_64 libstdc++-4.3.2-7.x86_64 libtiff-3.8.2-11.fc10.x86_64 zlib-1.2.3-18.fc9.x86_64
(gdb) r
The program being debugged has been started already.
Start it from the beginning? (y or n) n
Program not restarted.
(gdb) bt
#0  0x0000000000000000 in ?? ()
#1  0x00007ffff5d43f29 in _swrast_read_rgba_span (ctx=0x6251d0, rb=0x90e890, n=<value optimized out>, x=<value optimized out>,
    y=8, dstType=5126, rgba=0x7ffff5812010) at swrast/s_span.c:1590
#2  0x00007ffff5d42c12 in read_rgba_pixels (ctx=0x6251d0, x=8, y=8, width=1, height=1, format=6408, type=5126,
    pixels=0x7fffffffe020, packing=0x7fffffffdf30) at swrast/s_readpix.c:422
#3  0x00007ffff5d43516 in _swrast_ReadPixels (ctx=0x6251d0, x=8, y=8, width=1, height=1, format=6408, type=5126,
    packing=0x632bb0, pixels=0x7fffffffe020) at swrast/s_readpix.c:605
#4  0x00007ffff5db0787 in _mesa_ReadPixels (x=8, y=8, width=1, height=1, format=6408, type=5126, pixels=0x7fffffffe020)
    at main/readpix.c:191
#5  0x0000000000401ae2 in DoTest ()
#6  0x0000000000401cd3 in Display ()
#7  0x00007ffff78d9eef in processWindowWorkList (window=0x60fd00) at glut_event.c:1306
#8  0x00007ffff78dac1c in __glutProcessWindowWorkLists () at glut_event.c:1356
#9  glutMainLoop () at glut_event.c:1377
#10 0x00000000004020e0 in main ()

reproduce steps:
------------------------
1. xinit&
2. ./texrect-many