diff --git a/exa/exa_classic.c b/exa/exa_classic.c
index 12f398709..28cc42140 100644
--- a/exa/exa_classic.c
+++ b/exa/exa_classic.c
@@ -256,9 +256,10 @@ exaPixmapIsOffscreen_classic(PixmapPtr pPixmap)
     Bool ret;
 
     if (pExaScr->info->PixmapIsOffscreen) {
+	void* old_ptr = pPixmap->devPrivate.ptr;
 	pPixmap->devPrivate.ptr = ExaGetPixmapAddress(pPixmap);
 	ret = pExaScr->info->PixmapIsOffscreen(pPixmap);
-	pPixmap->devPrivate.ptr = NULL;
+	pPixmap->devPrivate.ptr = old_ptr;
     } else
 	ret = (pExaPixmap->offscreen && pExaPixmap->fb_ptr);