(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x00007ff821fc1b97 in radeon_cs_flush_indirect (pScrn=0x1b051b0) at radeon_kms.c:78
78    if (!info->cs->cdw)
(gdb) p info
$1 = (struct {...} *) 0x1b08450
(gdb) p info->cs
$2 = (struct radeon_cs *) 0x0
(gdb) bt
#0  0x00007ff821fc1b97 in radeon_cs_flush_indirect (pScrn=0x1b051b0) at radeon_kms.c:78
#1  0x00007ff821f87b9d in RadeonCompositeTileCP (pScrn=0x1b051b0, info=0x1b08450, pDst=<value optimized out>, srcX=0, srcY=0, maskX=<value optimized out>, maskY=27, 
    dstX=480, dstY=20, w=5, h=5) at radeon_exa_render.c:2182
#2  0x00007ff821f8ab05 in RadeonCompositeCP (pDst=<value optimized out>, srcX=<value optimized out>, srcY=<value optimized out>, maskX=<value optimized out>, 
    maskY=<value optimized out>, dstX=<value optimized out>, dstY=0, width=1146, height=916) at radeon_exa_render.c:2426
#3  0x00007ff821277b70 in ?? () from /usr/lib64/xorg/modules/libexa.so
#4  0x00007ff821279438 in ?? () from /usr/lib64/xorg/modules/libexa.so
#5  0x00000000004d5e97 in ?? ()
#6  0x00000000004cf335 in ?? ()
#7  0x000000000042dbf4 in ?? ()
#8  0x0000000000421d3a in _start ()