From 7c2bf6e925c38b8e3358f5046971b0d6086ddcf8 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 9 Feb 2011 15:34:53 -0800 Subject: [PATCH] [SCSI] target: Fix top-level configfs_subsystem default_group shutdown breakage This patch fixes two bugs uncovered during testing with slub_debug=FPUZ during module_exit() -> target_core_exit_configfs() with release of configfs subsystem consumer default groups, namely how this should be working with fs/configfs/dir.c:configfs_unregister_subsystem() release logic for struct config_group->default_group. The first issue involves configfs_unregister_subsystem() expecting to walk+drain the top-level subsys->su_group.default_groups directly in unlink_group(), and not directly from the configfs subsystem consumer for the top level struct config_group->default_groups. This patch drops the walk+drain of subsys->su_group.default_groups from TCM configfs subsystem consumer code, and moves the top-level ->default_groups kfree() after configfs_unregister_subsystem() has been called. The second issue involves calling core_alua_free_lu_gp(se_global->default_lu_gp) to release the default_lu_gp->lu_gp_group before configfs_unregister_subsystem() has been called. This patches also moves the core_alua_free_lu_gp() call to release default_lu_group->lu_gp_group after the subsys has been unregistered. Finally, this patch explictly clears the [lu_gp,alua,hba]_cg->default_groups pointers after kfree() to ensure that no stale memory is picked up from child struct config_group->default_group[] while configfs_unregister_subsystem() is called. Reported-by: Fubo Chen Signed-off-by: Nicholas A. Bellinger Signed-off-by: James Bottomley --- drivers/target/target_core_configfs.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c index 2764510798b0..1cb74d57ed5f 100644 --- a/drivers/target/target_core_configfs.c +++ b/drivers/target/target_core_configfs.c @@ -3178,8 +3178,7 @@ static void target_core_exit_configfs(void) config_item_put(item); } kfree(lu_gp_cg->default_groups); - core_alua_free_lu_gp(se_global->default_lu_gp); - se_global->default_lu_gp = NULL; + lu_gp_cg->default_groups = NULL; alua_cg = &se_global->alua_group; for (i = 0; alua_cg->default_groups[i]; i++) { @@ -3188,6 +3187,7 @@ static void target_core_exit_configfs(void) config_item_put(item); } kfree(alua_cg->default_groups); + alua_cg->default_groups = NULL; hba_cg = &se_global->target_core_hbagroup; for (i = 0; hba_cg->default_groups[i]; i++) { @@ -3196,15 +3196,17 @@ static void target_core_exit_configfs(void) config_item_put(item); } kfree(hba_cg->default_groups); - - for (i = 0; subsys->su_group.default_groups[i]; i++) { - item = &subsys->su_group.default_groups[i]->cg_item; - subsys->su_group.default_groups[i] = NULL; - config_item_put(item); - } + hba_cg->default_groups = NULL; + /* + * We expect subsys->su_group.default_groups to be released + * by configfs subsystem provider logic.. + */ + configfs_unregister_subsystem(subsys); kfree(subsys->su_group.default_groups); - configfs_unregister_subsystem(subsys); + core_alua_free_lu_gp(se_global->default_lu_gp); + se_global->default_lu_gp = NULL; + printk(KERN_INFO "TARGET_CORE[0]: Released ConfigFS Fabric" " Infrastructure\n"); -- 2.20.1