From 6156581e07bf02592c0c4ac54411530a35912d05 Mon Sep 17 00:00:00 2001 From: Staale Smedseng Date: Fri, 16 Apr 2010 15:02:23 +0200 Subject: [PATCH] Bug#51591 deadlock in the plugins+status+variables Potential deadlock situation involving LOCK_plugin, LOCK_global_system_variables and LOCK_status. This patch backports the fix from next-mr, unlocking LOCK_plugin before calling plugin->init() and add_status_vars(). --- sql/sql_plugin.cc | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/sql/sql_plugin.cc b/sql/sql_plugin.cc index 0706ef24881..87c0adc3133 100644 --- a/sql/sql_plugin.cc +++ b/sql/sql_plugin.cc @@ -1006,9 +1006,14 @@ void plugin_unlock_list(THD *thd, plugin_ref *list, uint count) static int plugin_initialize(struct st_plugin_int *plugin) { + int ret= 1; DBUG_ENTER("plugin_initialize"); safe_mutex_assert_owner(&LOCK_plugin); + uint state= plugin->state; + DBUG_ASSERT(state == PLUGIN_IS_UNINITIALIZED); + + pthread_mutex_unlock(&LOCK_plugin); if (plugin_type_initialize[plugin->plugin->type]) { if ((*plugin_type_initialize[plugin->plugin->type])(plugin)) @@ -1027,8 +1032,7 @@ static int plugin_initialize(struct st_plugin_int *plugin) goto err; } } - - plugin->state= PLUGIN_IS_READY; + state= PLUGIN_IS_READY; // plugin->init() succeeded if (plugin->plugin->status_vars) { @@ -1047,7 +1051,8 @@ static int plugin_initialize(struct st_plugin_int *plugin) if (add_status_vars(array)) // add_status_vars makes a copy goto err; #else - add_status_vars(plugin->plugin->status_vars); // add_status_vars makes a copy + if (add_status_vars(plugin->plugin->status_vars)) + goto err; #endif /* FIX_LATER */ } @@ -1067,9 +1072,12 @@ static int plugin_initialize(struct st_plugin_int *plugin) } } - DBUG_RETURN(0); + ret= 0; + err: - DBUG_RETURN(1); + pthread_mutex_lock(&LOCK_plugin); + plugin->state= state; + DBUG_RETURN(ret); }