Comment 4 for bug 550850

Reproducing this with drm.debug=1 produced more output. Here is what I hope is the relevant part from dmesg:

Mar 31 22:38:46 martin-laptop kernel: [ 851.833384] [drm:drm_ioctl], pid=829, cmd=0xc0086464, nr=0x64, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.836186] [drm:drm_ioctl], pid=1619, cmd=0xc0086464, nr=0x64, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.836219] [drm:drm_ioctl], pid=1619, cmd=0xc0086464, nr=0x64, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.838215] [drm:drm_ioctl], pid=1619, cmd=0xc0086464, nr=0x64, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841233] [drm:drm_ioctl], pid=829, cmd=0xc01c64a3, nr=0xa3, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841807] [drm:drm_ioctl], pid=1619, cmd=0xc010640b, nr=0x0b, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841837] [drm:drm_ioctl], pid=1619, cmd=0xc00c6469, nr=0x69, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841845] [drm:radeon_gem_get_tiling_ioctl],
Mar 31 22:38:46 martin-laptop kernel: [ 851.841859] [drm:drm_ioctl], pid=1619, cmd=0xc010640b, nr=0x0b, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841867] [drm:drm_ioctl], pid=1619, cmd=0xc00c6469, nr=0x69, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841873] [drm:radeon_gem_get_tiling_ioctl],
Mar 31 22:38:46 martin-laptop kernel: [ 851.841882] [drm:drm_ioctl], pid=1619, cmd=0x40086409, nr=0x09, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.841893] [drm:drm_ioctl], pid=1619, cmd=0x40086409, nr=0x09, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.842360] [drm:drm_ioctl], pid=1619, cmd=0xc008646a, nr=0x6a, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.842394] [drm:drm_ioctl], pid=1619, cmd=0xc0206466, nr=0x66, dev 0xe200, auth=1
Mar 31 22:38:46 martin-laptop kernel: [ 851.842442] [drm:radeon_cs_ioctl] *ERROR* Failed to parse relocation !

Does that help? Is there anything else I can do to provide more information?