From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 173BAC43331 for ; Wed, 13 Nov 2019 09:30:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EAF782196E for ; Wed, 13 Nov 2019 09:30:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727420AbfKMJaO (ORCPT ); Wed, 13 Nov 2019 04:30:14 -0500 Received: from relay.sw.ru ([185.231.240.75]:39208 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726613AbfKMJaN (ORCPT ); Wed, 13 Nov 2019 04:30:13 -0500 Received: from finist_cl7.qa.sw.ru ([10.94.4.83] helo=finist-ce7.sw.ru) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1iUoyE-00062s-Rr; Wed, 13 Nov 2019 12:29:51 +0300 From: Konstantin Khorenko To: Jessica Yu , Prarit Bhargava , Barret Rhoden Cc: Konstantin Khorenko , Andrey Ryabinin , linux-kernel@vger.kernel.org, David Arcari , Heiko Carstens Subject: [PATCH 0/1] kernel/module.c: don't allow modprobe to hang forever on a module load Date: Wed, 13 Nov 2019 12:29:49 +0300 Message-Id: <20191113092950.15556-1-khorenko@virtuozzo.com> X-Mailer: git-send-email 2.15.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After commit 6e6de3dee51a ("kernel/module.c: Only return -EEXIST for modules that have finished loading") the simple test leads to hanged modprobe process (INTERRUPTIBLE): 1. Make sure nft_ct module is not used by your firewall rules. 2. Run 3 copies of # export i=0; while true; if [[ $(($i % 100)) -eq 0 ]] ; then \ echo "i=$i"; fi; do modprobe nft_ct; i=$(($i + 1)); done 3. Run 2 copies of # while true; do rmmod nft_ct; done Hanged "modprobe" process will appear in ~ 10 seconds. # cat /proc/30184/stack [<0>] load_module+0x53f/0x2060 [<0>] __do_sys_finit_module+0xd2/0x100 [<0>] do_syscall_64+0x5b/0x1c0 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Konstantin Khorenko (1): kernel/module.c: wakeup processes in module_wq on module unload kernel/module.c | 2 ++ 1 file changed, 2 insertions(+) -- 2.15.1