r300: fix wrong call in last commit
diff --git a/src/gallium/drivers/r300/r300_render.c b/src/gallium/drivers/r300/r300_render.c
index 68abfbe..cb2d8d4 100644
--- a/src/gallium/drivers/r300/r300_render.c
+++ b/src/gallium/drivers/r300/r300_render.c
@@ -311,7 +311,7 @@
         indexSize = 2;
     }
 
-    r300_emit_buffer_validate(r300->winsys);
+    r300_emit_buffer_validate(r300);
 
     if (!r300->winsys->add_buffer(r300->winsys, indexBuffer,
                                   RADEON_GEM_DOMAIN_GTT, 0)) {