diff --git a/drivers/char/drm/radeon_cp.c b/drivers/char/drm/radeon_cp.c
index 335423c..24fca8e 100644
--- a/drivers/char/drm/radeon_cp.c
+++ b/drivers/char/drm/radeon_cp.c
@@ -1679,7 +1679,7 @@
 			dev_priv->gart_info.bus_addr =
 			    dev_priv->pcigart_offset + dev_priv->fb_location;
 			dev_priv->gart_info.mapping.offset =
-			    dev_priv->gart_info.bus_addr;
+			    dev_priv->pcigart_offset + dev_priv->fb_aper_offset;
 			dev_priv->gart_info.mapping.size =
 			    dev_priv->gart_info.table_size;
 
@@ -2275,7 +2275,8 @@
 	if (ret != 0)
 		return ret;
 
-	ret = drm_addmap(dev, drm_get_resource_start(dev, 0),
+	dev_priv->fb_aper_offset = drm_get_resource_start(dev, 0);
+	ret = drm_addmap(dev, dev_priv->fb_aper_offset,
 			 drm_get_resource_len(dev, 0), _DRM_FRAME_BUFFER,
 			 _DRM_WRITE_COMBINING, &map);
 	if (ret != 0)
diff --git a/drivers/char/drm/radeon_drv.h b/drivers/char/drm/radeon_drv.h
index e4077bc..bfbb60a 100644
--- a/drivers/char/drm/radeon_drv.h
+++ b/drivers/char/drm/radeon_drv.h
@@ -293,6 +293,7 @@
 
 	/* starting from here on, data is preserved accross an open */
 	uint32_t flags;		/* see radeon_chip_flags */
+	unsigned long fb_aper_offset;
 } drm_radeon_private_t;
 
 typedef struct drm_radeon_buf_priv {
diff --git a/drivers/char/drm/sis_mm.c b/drivers/char/drm/sis_mm.c
index 6be1c57..a6b7ccd 100644
--- a/drivers/char/drm/sis_mm.c
+++ b/drivers/char/drm/sis_mm.c
@@ -134,6 +134,7 @@
 		      dev_priv->agp_initialized)) {
 		DRM_ERROR
 		    ("Attempt to allocate from uninitialized memory manager.\n");
+		mutex_unlock(&dev->struct_mutex);
 		return -EINVAL;
 	}