From patchwork Thu Jul 30 12:00:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kirill Tkhai X-Patchwork-Id: 11692865 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 42D1813B1 for ; Thu, 30 Jul 2020 12:01:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 271FB208A9 for ; Thu, 30 Jul 2020 12:01:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728667AbgG3MBH (ORCPT ); Thu, 30 Jul 2020 08:01:07 -0400 Received: from relay.sw.ru ([185.231.240.75]:57080 "EHLO relay3.sw.ru" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728592AbgG3MBA (ORCPT ); Thu, 30 Jul 2020 08:01:00 -0400 Received: from [192.168.15.64] (helo=localhost.localdomain) by relay3.sw.ru with esmtp (Exim 4.93) (envelope-from ) id 1k17Ep-0002zc-Ew; Thu, 30 Jul 2020 15:00:43 +0300 Subject: [PATCH 18/23] uts: Free uts namespace one RCU grace period after final counter put From: Kirill Tkhai To: viro@zeniv.linux.org.uk, adobriyan@gmail.com, davem@davemloft.net, ebiederm@xmission.com, akpm@linux-foundation.org, christian.brauner@ubuntu.com, areber@redhat.com, serge@hallyn.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, ktkhai@virtuozzo.com Date: Thu, 30 Jul 2020 15:00:57 +0300 Message-ID: <159611045706.535980.12888496197045005870.stgit@localhost.localdomain> In-Reply-To: <159611007271.535980.15362304262237658692.stgit@localhost.localdomain> References: <159611007271.535980.15362304262237658692.stgit@localhost.localdomain> User-Agent: StGit/0.19 MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This is needed to link uts_ns into ns_idr in next patch. Signed-off-by: Kirill Tkhai --- include/linux/utsname.h | 1 + kernel/utsname.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/linux/utsname.h b/include/linux/utsname.h index 2b1737c9b244..b783d0fe6ca4 100644 --- a/include/linux/utsname.h +++ b/include/linux/utsname.h @@ -25,6 +25,7 @@ struct uts_namespace { struct user_namespace *user_ns; struct ucounts *ucounts; struct ns_common ns; + struct rcu_head rcu; } __randomize_layout; extern struct uts_namespace init_uts_ns; diff --git a/kernel/utsname.c b/kernel/utsname.c index b1ac3ca870f2..aebf4df5f592 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -103,12 +103,20 @@ struct uts_namespace *copy_utsname(unsigned long flags, return new_ns; } +static void free_uts_ns_rcu(struct rcu_head *head) +{ + struct uts_namespace *ns; + + ns = container_of(head, struct uts_namespace, rcu); + kmem_cache_free(uts_ns_cache, ns); +} + void free_uts_ns(struct uts_namespace *ns) { dec_uts_namespaces(ns->ucounts); put_user_ns(ns->user_ns); ns_free_inum(&ns->ns); - kmem_cache_free(uts_ns_cache, ns); + call_rcu(&ns->rcu, free_uts_ns_rcu); } static inline struct uts_namespace *to_uts_ns(struct ns_common *ns)