From patchwork Wed Aug 9 12:50:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Jialin X-Patchwork-Id: 712065 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11C08EB64DD for ; Wed, 9 Aug 2023 13:16:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232102AbjHINQU (ORCPT ); Wed, 9 Aug 2023 09:16:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50740 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232820AbjHINQT (ORCPT ); Wed, 9 Aug 2023 09:16:19 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6B1D210B for ; Wed, 9 Aug 2023 06:16:18 -0700 (PDT) Received: from kwepemm600003.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4RLVK51mXRzZfqR; Wed, 9 Aug 2023 20:50:33 +0800 (CST) Received: from hulk-vt.huawei.com (10.67.174.118) by kwepemm600003.china.huawei.com (7.193.23.202) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Wed, 9 Aug 2023 20:51:44 +0800 From: Lu Jialin To: Steffen Klassert , Daniel Jordan CC: Lu Jialin , Subject: [PATCH] crypto:padata: Fix return err for PADATA_RESET Date: Wed, 9 Aug 2023 12:50:48 +0000 Message-ID: <20230809125048.503619-1-lujialin4@huawei.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-Originating-IP: [10.67.174.118] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemm600003.china.huawei.com (7.193.23.202) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org We found a hungtask bug in test_aead_vec_cfg as follows: INFO: task cryptomgr_test:391009 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Call trace: __switch_to+0x98/0xe0 __schedule+0x6c4/0xf40 schedule+0xd8/0x1b4 schedule_timeout+0x474/0x560 wait_for_common+0x368/0x4e0 wait_for_completion+0x20/0x30 test_aead_vec_cfg+0xab4/0xd50 test_aead+0x144/0x1f0 alg_test_aead+0xd8/0x1e0 alg_test+0x634/0x890 cryptomgr_test+0x40/0x70 kthread+0x1e0/0x220 ret_from_fork+0x10/0x18 Kernel panic - not syncing: hung_task: blocked tasks For padata_do_parallel, when the return err is 0 or -EBUSY, it will call wait_for_completion(&wait->completion) in test_aead_vec_cfg. In normal case, aead_request_complete() will be called in pcrypt_aead_serial and the return err is 0 for padata_do_parallel. But, when pinst->flags is PADATA_RESET, the return err is -EBUSY for padata_do_parallel, and it won't call aead_request_complete(). Therefore, test_aead_vec_cfg will hung at wait_for_completion(&wait->completion), which will cause hungtask. The problem comes as following: (padata_do_parallel) | rcu_read_lock_bh(); | err = -EINVAL; | (padata_replace) | pinst->flags |= PADATA_RESET; err = -EBUSY | if (pinst->flags & PADATA_RESET) | rcu_read_unlock_bh() | return err | In order to resolve the problem, change the return err to -EINVAL when pinst->flags is set PADATA_RESET. Signed-off-by: Lu Jialin --- kernel/padata.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/padata.c b/kernel/padata.c index 222d60195de6..cc326ffb209a 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -202,7 +202,6 @@ int padata_do_parallel(struct padata_shell *ps, *cb_cpu = cpu; } - err = -EBUSY; if ((pinst->flags & PADATA_RESET)) goto out;