i915: Fix GetBufferSubData in the case of a system-memory BO.

Bug #23760 (crashes in wine)

1 files changed, 4 insertions, 1 deletions

diff --git a/src/mesa/drivers/dri/intel/intel_buffer_objects.c b/src/mesa/drivers/dri/intel/intel_buffer_objects.c
index 2e6b77824d..db0de0343a 100644
--- a/src/mesa/drivers/dri/intel/intel_buffer_objects.c
+++ b/src/mesa/drivers/dri/intel/intel_buffer_objects.c
@@ -209,7 +209,10 @@ intel_bufferobj_get_subdata(GLcontext * ctx,
    struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
 
    assert(intel_obj);
-   dri_bo_get_subdata(intel_obj->buffer, offset, size, data);
+   if (intel_obj->sys_buffer)
+      memcpy(data, (char *)intel_obj->sys_buffer + offset, size);
+   else
+      dri_bo_get_subdata(intel_obj->buffer, offset, size, data);
 }