diff -r d70971a3ae80 -r f3807a135e43 mercurial/wireproto.py
--- a/mercurial/wireproto.py	Fri Feb 10 18:17:20 2017 +0100
+++ b/mercurial/wireproto.py	Fri Feb 10 18:20:58 2017 +0100
@@ -839,7 +839,24 @@
             raise error.Abort(bundle2requiredmain,
                               hint=bundle2requiredhint)
 
-    chunks = exchange.getbundlechunks(repo, 'serve', **opts)
+    #chunks = exchange.getbundlechunks(repo, 'serve', **opts)
+    try:
+        chunks = exchange.getbundlechunks(repo, 'serve', **opts)
+    except error.Abort as exc:
+        # cleanly forward Abort error to the client
+        if not exchange.bundle2requested(opts.get('bundlecaps')):
+            if proto.name == 'http':
+                return ooberror(str(exc) + '\n')
+            raise # cannot do better for bundle1 + ssh
+        # bundle2 request expect a bundle2 reply
+        bundler = bundle2.bundle20(repo.ui)
+        manargs = [('message', str(exc))]
+        advargs = []
+        if exc.hint is not None:
+            advargs.append(('hint', exc.hint))
+        bundler.addpart(bundle2.bundlepart('error:abort',
+                                           manargs, advargs))
+        return streamres(gen=bundler.getchunks(), v1compressible=True)
     return streamres(gen=chunks, v1compressible=True)
 
 @wireprotocommand('heads')