diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -5575,8 +5575,7 @@ def unbundle(ui, repo, fname1, *fnames, 
         for fname in fnames:
             f = url.open(ui, fname)
             gen = changegroup.readbundle(f, fname)
-            modheads = repo.addchangegroup(gen, 'unbundle', 'bundle:' + fname,
-                                           lock=lock)
+            modheads = repo.addchangegroup(gen, 'unbundle', 'bundle:' + fname)
         bookmarks.updatecurrentbookmark(repo, wc.node(), wc.branch())
     finally:
         lock.release()
diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1527,8 +1527,7 @@ class localrepository(repo.repository):
                                            "changegroupsubset."))
                 else:
                     cg = remote.changegroupsubset(fetch, heads, 'pull')
-                result = self.addchangegroup(cg, 'pull', remote.url(),
-                                             lock=lock)
+                result = self.addchangegroup(cg, 'pull', remote.url())
             phases.advanceboundary(self, 0, common)
         finally:
             lock.release()
@@ -1583,8 +1582,7 @@ class localrepository(repo.repository):
                         ret = remote.unbundle(cg, remote_heads, 'push')
                     else:
                         # we return an integer indicating remote head count change
-                        ret = remote.addchangegroup(cg, 'push', self.url(),
-                                                    lock=lock)
+                        ret = remote.addchangegroup(cg, 'push', self.url())
                 # if we don't push, the common data is already useful
                 # everything exchange is public for now
                 phases.advanceboundary(self, 0, fut)
@@ -1849,12 +1847,10 @@ class localrepository(repo.repository):
 
         return changegroup.unbundle10(util.chunkbuffer(gengroup()), 'UN')
 
-    def addchangegroup(self, source, srctype, url, emptyok=False, lock=None):
+    def addchangegroup(self, source, srctype, url, emptyok=False):
         """Add the changegroup returned by source.read() to this repo.
         srctype is a string like 'push', 'pull', or 'unbundle'.  url is
         the URL of the repo where this changegroup is coming from.
-        If lock is not None, the function takes ownership of the lock
-        and releases it after the changegroup is added.
 
         Return an integer summarizing the change to this repo:
         - nothing changed or no source: 0
@@ -2019,8 +2015,6 @@ class localrepository(repo.repository):
 
         finally:
             tr.release()
-            if lock:
-                lock.release()
         # never return 0 here:
         if dh < 0:
             return dh - 1
diff --git a/mercurial/sshserver.py b/mercurial/sshserver.py
--- a/mercurial/sshserver.py
+++ b/mercurial/sshserver.py
@@ -142,8 +142,8 @@ class sshserver(object):
 
         self.sendresponse("")
         cg = changegroup.unbundle10(self.fin, "UN")
-        r = self.repo.addchangegroup(cg, 'serve', self._client(),
-                                     lock=self.lock)
+        r = self.repo.addchangegroup(cg, 'serve', self._client())
+        self.lock.release()
         return str(r)
 
     def _client(self):
diff --git a/mercurial/wireproto.py b/mercurial/wireproto.py
--- a/mercurial/wireproto.py
+++ b/mercurial/wireproto.py
@@ -574,8 +574,7 @@ def unbundle(repo, proto, heads):
             gen = changegroupmod.readbundle(fp, None)
 
             try:
-                r = repo.addchangegroup(gen, 'serve', proto._client(),
-                                        lock=lock)
+                r = repo.addchangegroup(gen, 'serve', proto._client())
             except util.Abort, inst:
                 sys.stderr.write("abort: %s\n" % inst)
         finally: