From 08e8733e51ea4027a705391ede57bbec17f4137b Mon Sep 17 00:00:00 2001
From: Noriko Hosoi <nhosoi@redhat.com>
Date: Jul 01 2011 22:25:17 +0000
Subject: Bug 711679 - unresponsive LDAP service when deleting vlv on replica


https://bugzilla.redhat.com/show_bug.cgi?id=711679

Description: Normal operation acquires rlock on be_lock, then locks
inst_config_mutex.  Function instance_set_busy_and_readonly used to
lock them in the opposite order, which caused the server deadlock.
This patch fixes it by releasing inst_config_mutex before acquiring
wlock on be_lock in slapi_mtn_be_set_readonly.
(cherry picked from commit b554264e6b6056414d17044991c3b5ec839d0981)
(cherry picked from commit fc7ed8fb8432827b5c4022dbbc445f5e121f4d4a)

---

diff --git a/ldap/servers/slapd/back-ldbm/misc.c b/ldap/servers/slapd/back-ldbm/misc.c
index c8b3b7f..9255ddb 100644
--- a/ldap/servers/slapd/back-ldbm/misc.c
+++ b/ldap/servers/slapd/back-ldbm/misc.c
@@ -199,9 +199,14 @@ int instance_set_busy_and_readonly(ldbm_instance *inst)
     } else {
         inst->inst_flags &= ~INST_FLAG_READONLY;
     }
+    /* 
+     * Normally, acquire rlock on be_lock, then lock inst_config_mutex.
+     * instance_set_busy_and_readonly should release inst_config_mutex
+     * before acquiring wlock on be_lock in slapi_mtn_be_set_readonly.
+     */
+    PR_Unlock(inst->inst_config_mutex);
     slapi_mtn_be_set_readonly(inst->inst_be, 1);
 
-    PR_Unlock(inst->inst_config_mutex);
     return 0;
 }