From f091c9de34e2c8fcaf93966180226dea52f90e38 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fe=CC=81lix=20Belzunce=20Arcos?= <fbelzunc@gmail.com>
Date: Fri, 28 Apr 2017 13:56:36 +0200
Subject: [PATCH] [JENKINS-43936] Only migrate legacy users once per restart

---
 core/src/main/java/hudson/model/User.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/src/main/java/hudson/model/User.java b/core/src/main/java/hudson/model/User.java
index 38b5b6feeccb..0ebd2342e91d 100644
--- a/core/src/main/java/hudson/model/User.java
+++ b/core/src/main/java/hudson/model/User.java
@@ -432,7 +432,7 @@ public synchronized void doSubmitDescription( StaplerRequest req, StaplerRespons
             byNameLock.readLock().unlock();
         }
         final File configFile = getConfigFileFor(id);
-        if (!configFile.isFile() && !configFile.getParentFile().isDirectory()) {
+        if (u == null && !configFile.isFile() && !configFile.getParentFile().isDirectory()) {
             // check for legacy users and migrate if safe to do so.
             File[] legacy = getLegacyConfigFilesFor(id);
             if (legacy != null && legacy.length > 0) {