From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936872AbeBUNbT (ORCPT ); Wed, 21 Feb 2018 08:31:19 -0500 Received: from mx2.suse.de ([195.135.220.15]:49074 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934789AbeBUN3m (ORCPT ); Wed, 21 Feb 2018 08:29:42 -0500 From: Petr Mladek To: Jiri Kosina , Josh Poimboeuf , Miroslav Benes Cc: Jason Baron , Joe Lawrence , Jessica Yu , Evgenii Shatokhin , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, Petr Mladek Subject: [PATCH v8 2/8] livepatch: Free only structures with initialized kobject Date: Wed, 21 Feb 2018 14:29:08 +0100 Message-Id: <20180221132914.4809-3-pmladek@suse.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20180221132914.4809-1-pmladek@suse.com> References: <20180221132914.4809-1-pmladek@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We are going to add a feature called atomic replace. It will allow to create a patch that would replace all already registered patches. For this, we will need to dynamically create funcs and objects for functions that are no longer patched. We will want to reuse the existing init() and free() functions. Up to now, the free() functions checked a limit and were called only for structures with initialized kobject. But we will want to call them also for structures that were allocated but where the kobject was not initialized yet. This patch removes the limit. It calls klp_free*() functions for all structures. But only the ones with initialized kobject are freed. The handling of un-initialized structures will be added later with the support for dynamic structures. This patch does not change the existing behavior. Signed-off-by: Petr Mladek Cc: Josh Poimboeuf Cc: Jessica Yu Cc: Jiri Kosina Cc: Jason Baron Acked-by: Miroslav Benes --- kernel/livepatch/core.c | 44 ++++++++++++++++++-------------------------- 1 file changed, 18 insertions(+), 26 deletions(-) diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 1d525f4a270a..69bde95e76f8 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -653,17 +653,15 @@ static struct kobj_type klp_ktype_func = { .sysfs_ops = &kobj_sysfs_ops, }; -/* - * Free all functions' kobjects in the array up to some limit. When limit is - * NULL, all kobjects are freed. - */ -static void klp_free_funcs_limited(struct klp_object *obj, - struct klp_func *limit) +/* Free all funcs that have the kobject initialized. */ +static void klp_free_funcs(struct klp_object *obj) { struct klp_func *func; - for (func = obj->funcs; func->old_name && func != limit; func++) - kobject_put(&func->kobj); + klp_for_each_func(obj, func) { + if (func->kobj.state_initialized) + kobject_put(&func->kobj); + } } /* Clean up when a patched object is unloaded */ @@ -677,24 +675,23 @@ static void klp_free_object_loaded(struct klp_object *obj) func->old_addr = 0; } -/* - * Free all objects' kobjects in the array up to some limit. When limit is - * NULL, all kobjects are freed. - */ -static void klp_free_objects_limited(struct klp_patch *patch, - struct klp_object *limit) +/* Free all funcs and objects that have the kobject initialized. */ +static void klp_free_objects(struct klp_patch *patch) { struct klp_object *obj; - for (obj = patch->objs; obj->funcs && obj != limit; obj++) { - klp_free_funcs_limited(obj, NULL); - kobject_put(&obj->kobj); + klp_for_each_object(patch, obj) { + klp_free_funcs(obj); + + if (obj->kobj.state_initialized) + kobject_put(&obj->kobj); } } static void klp_free_patch(struct klp_patch *patch) { - klp_free_objects_limited(patch, NULL); + klp_free_objects(patch); + if (!list_empty(&patch->list)) list_del(&patch->list); } @@ -791,21 +788,16 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj) klp_for_each_func(obj, func) { ret = klp_init_func(obj, func); if (ret) - goto free; + return ret; } if (klp_is_object_loaded(obj)) { ret = klp_init_object_loaded(patch, obj); if (ret) - goto free; + return ret; } return 0; - -free: - klp_free_funcs_limited(obj, func); - kobject_put(&obj->kobj); - return ret; } static int klp_init_patch(struct klp_patch *patch) @@ -842,7 +834,7 @@ static int klp_init_patch(struct klp_patch *patch) return 0; free: - klp_free_objects_limited(patch, obj); + klp_free_objects(patch); mutex_unlock(&klp_mutex); -- 2.13.6