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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 1644DC433ED for ; Wed, 14 Apr 2021 19:14:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E57BB61220 for ; Wed, 14 Apr 2021 19:14:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352290AbhDNTPF (ORCPT ); Wed, 14 Apr 2021 15:15:05 -0400 Received: from mga18.intel.com ([134.134.136.126]:13176 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352044AbhDNTPB (ORCPT ); Wed, 14 Apr 2021 15:15:01 -0400 IronPort-SDR: UQ6JjfZKLJ7SDVklFzMRAHTTvh4bkBXWu9wfS43FY2BfRcCfI+WpyTSMBY3QSlttIEHJN1iWEA 2aapL83wcwsw== X-IronPort-AV: E=McAfee;i="6200,9189,9954"; a="182217977" X-IronPort-AV: E=Sophos;i="5.82,223,1613462400"; d="scan'208";a="182217977" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2021 12:14:36 -0700 IronPort-SDR: JHSXI5ogPMf+nKkJI5QO2UwfF7lt/5uE0WflR1ZvTeC7DrX94bEfvJM0dmZ/wIz52W+oHeEUg5 W0ZA3rpfkMwQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,223,1613462400"; d="scan'208";a="452592279" Received: from um.fi.intel.com (HELO um) ([10.237.72.62]) by fmsmga002.fm.intel.com with ESMTP; 14 Apr 2021 12:14:34 -0700 From: Alexander Shishkin To: Greg Kroah-Hartman , Andy Shevchenko Cc: linux-kernel@vger.kernel.org, alexander.shishkin@linux.intel.com Subject: Re: [PATCH 2/7] stm class: Replace uuid_t with plain u8 uuid[16] In-Reply-To: References: <20210414171251.14672-1-alexander.shishkin@linux.intel.com> <20210414171251.14672-3-alexander.shishkin@linux.intel.com> Date: Wed, 14 Apr 2021 22:14:34 +0300 Message-ID: <87sg3sfzl1.fsf@ashishki-desk.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Greg Kroah-Hartman writes: >> Using raw buffer APIs against uuid_t / guid_t. > > So you want to do that, or you do not want to do that? Totally > confused, My understanding is that: 1) generate_random_uuid() use is allegedly bad even though it's in their header, 2) poking directly at the byte array inside uuid_t is bad, even though, again, header. It is, indeed, not ideal. If agreeable, I'll update this patch to the below and respin the whole series. >From 02340f8c7c17ace028040a35553c33cce8f3bce4 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 22 Apr 2020 16:02:20 +0300 Subject: [PATCH] stm class: Use correct UUID APIs It appears that the STM code didn't manage to accurately decypher the delicate inner workings of an alternative thought process behind the UUID API and directly called generate_random_uuid() that clearly needs to be a static function in lib/uuid.c. At the same time, said STM code is poking directly at the byte array inside the uuid_t when it uses the UUID for its internal purposes. Fix these two transgressions by using intended APIs instead. Signed-off-by: Andy Shevchenko [ash: changed back to uuid_t and updated the commit message] Signed-off-by: Alexander Shishkin --- drivers/hwtracing/stm/p_sys-t.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/stm/p_sys-t.c b/drivers/hwtracing/stm/p_sys-t.c index 360b5c03df95..8254971c02e7 100644 --- a/drivers/hwtracing/stm/p_sys-t.c +++ b/drivers/hwtracing/stm/p_sys-t.c @@ -92,7 +92,7 @@ static void sys_t_policy_node_init(void *priv) { struct sys_t_policy_node *pn = priv; - generate_random_uuid(pn->uuid.b); + uuid_gen(&pn->uuid); } static int sys_t_output_open(void *priv, struct stm_output *output) @@ -292,6 +292,7 @@ static ssize_t sys_t_write(struct stm_data *data, struct stm_output *output, unsigned int m = output->master; const unsigned char nil = 0; u32 header = DATA_HEADER; + u8 uuid[UUID_SIZE]; ssize_t sz; /* We require an existing policy node to proceed */ @@ -322,7 +323,8 @@ static ssize_t sys_t_write(struct stm_data *data, struct stm_output *output, return sz; /* GUID */ - sz = stm_data_write(data, m, c, false, op->node.uuid.b, UUID_SIZE); + export_uuid(uuid, &op->node.uuid); + sz = stm_data_write(data, m, c, false, uuid, sizeof(op->node.uuid)); if (sz <= 0) return sz; -- 2.30.2