Description of problem:

Using 6.13.0-0.12.20091119git437113124 as requested on bug 528390 gave me a suddenly gave me a totally unresponsive system twice. No capslock, no ctrl-alt-f2, no ctrl-alt-del.

I could ssh to the machine, and X used all cpu.

Nothing interesting in the logs - except for pulse complaining that some deadlines had been missed.

However:
(gdb) thread apply all bt

Thread 1 (Thread 0xb78b2760 (LWP 1413)):
#0  0x00d9c424 in __kernel_vsyscall ()
#1  0x00549e39 in ioctl () at ../sysdeps/unix/syscall-template.S:82
#2  0x04cb888e in drmIoctl (fd=<value optimized out>,
    request=<value optimized out>, arg=<value optimized out>) at xf86drm.c:188
#3  0x04cb8cd3 in drmCommandNone (fd=<value optimized out>,
    drmCommandIndex=<value optimized out>) at xf86drm.c:2307
#4  0x003943a4 in RADEONDownloadFromScreenCP (pSrc=<value optimized out>,
    x=<value optimized out>, y=<value optimized out>, w=<value optimized out>,
    h=<value optimized out>, dst=<value optimized out>,
    dst_pitch=<value optimized out>) at radeon_exa_funcs.c:734
#5  0x0013c85a in exaCopyDirty (migrate=<value optimized out>,
    pValidDst=<value optimized out>, pValidSrc=<value optimized out>,
    transfer=<value optimized out>, fallback_index=<value optimized out>,
    sync=<value optimized out>) at exa_migration_classic.c:217
#6  0x0013cdc7 in exaCopyDirtyToSys (migrate=<value optimized out>)
    at exa_migration_classic.c:278
#7  0x0013cf2b in exaDoMoveOutPixmap (migrate=<value optimized out>)
    at exa_migration_classic.c:393
#8  0x0013a1a9 in exaMoveOutPixmap (pPixmap=<value optimized out>)
    at exa.c:1207
#9  0x0013c552 in exaPixmapSave (pScreen=<value optimized out>,
---Type <return> to continue, or q <return> to quit---
    area=<value optimized out>) at exa_migration_classic.c:433
#10 0x00142f0f in ExaOffscreenKickOut (pScreen=0x9085f70, area=0x94fc040)
    at exa_offscreen.c:68
#11 0x001439c2 in exaOffscreenAlloc (pScreen=<value optimized out>,
    size=<value optimized out>, align=<value optimized out>,
    locked=<value optimized out>, save=<value optimized out>,
    privData=<value optimized out>) at exa_offscreen.c:257
#12 0x0013cce4 in exaDoMoveInPixmap (migrate=0xbfb98c08)
    at exa_migration_classic.c:342
#13 0x0013d642 in exaDoMigration_classic (pixmaps=<value optimized out>,
    npixmaps=<value optimized out>, can_accel=<value optimized out>)
    at exa_migration_classic.c:707
#14 0x0013a27b in exaDoMigration (pixmaps=<value optimized out>,
    npixmaps=<value optimized out>, can_accel=<value optimized out>)
    at exa.c:1181
#15 0x0013f9ff in exaFillRegionSolid (pDrawable=0x934ff58,
    pRegion=<value optimized out>, pixel=<value optimized out>,
    planemask=<value optimized out>, alu=<value optimized out>,
    clientClipType=<value optimized out>) at exa_accel.c:999
#16 0x00140633 in exaPolyFillRect (pDrawable=<value optimized out>,
    pGC=<value optimized out>, nrect=<value optimized out>,
    prect=<value optimized out>) at exa_accel.c:800
#17 0x0811c256 in damagePolyFillRect (pDrawable=<value optimized out>,
---Type <return> to continue, or q <return> to quit---
    pGC=<value optimized out>, nRects=<value optimized out>,
    pRects=<value optimized out>) at damage.c:1404
#18 0x0806bd00 in ProcPolyFillRectangle (client=<value optimized out>)
    at dispatch.c:1945
#19 0x0806e1f7 in Dispatch () at dispatch.c:445
#20 0x080628c5 in main (argc=<value optimized out>,
    argv=<value optimized out>, envp=<value optimized out>) at main.c:285
(gdb)


Version-Release number of selected component (if applicable):

xorg-x11-drv-ati-6.13.0-0.12.20091119git437113124.fc12.i686
kernel-PAE-2.6.31.6-145.fc12.i686