commit e8b131407cccd1de750ad44a94da72d19125c18e
Author: Michel Dänzer <michel.daenzer@amd.com>
Date:   Wed Aug 6 16:33:43 2014 +0900

    r600g/radeon: Don't try to allocate CMASK BO of size 0

diff --git a/src/gallium/drivers/radeon/r600_texture.c b/src/gallium/drivers/radeon/r600_texture.c
index 482bbff..0ecbb9e 100644
--- a/src/gallium/drivers/radeon/r600_texture.c
+++ b/src/gallium/drivers/radeon/r600_texture.c
@@ -463,6 +463,8 @@ static void r600_texture_alloc_cmask_separate(struct r600_common_screen *rscreen
 	} else {
 		r600_texture_get_cmask_info(rscreen, rtex, &rtex->cmask);
 	}
+	if (rtex->cmask.size == 0)
+		return;
 
 	rtex->cmask_buffer = (struct r600_resource *)
 		pipe_buffer_create(&rscreen->b, PIPE_BIND_CUSTOM,