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=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 F2304C433DF for ; Mon, 29 Jun 2020 20:50:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D603E206F1 for ; Mon, 29 Jun 2020 20:50:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389412AbgF2Uu6 (ORCPT ); Mon, 29 Jun 2020 16:50:58 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:42333 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387763AbgF2Uuu (ORCPT ); Mon, 29 Jun 2020 16:50:50 -0400 Received: from localhost.localdomain (unknown [176.88.144.104]) (Authenticated sender: cengiz@kernel.wtf) by relay10.mail.gandi.net (Postfix) with ESMTPSA id 8516C24000E; Mon, 29 Jun 2020 20:50:45 +0000 (UTC) From: Cengiz Can To: daniel.thompson@linaro.org Cc: andriy.shevchenko@linux.intel.com, cengiz@kernel.wtf, dianders@chromium.org, jason.wessel@windriver.com, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org, pmladek@suse.com, sumit.garg@linaro.org Subject: [PATCH v2] kdb: remove unnecessary null check of dbg_io_ops Date: Mon, 29 Jun 2020 23:50:13 +0300 Message-Id: <20200629205012.3263-1-cengiz@kernel.wtf> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200629153756.cxg74nec3repa4lu@holly.lan> References: <20200629153756.cxg74nec3repa4lu@holly.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org `kdb_msg_write` operates on a global `struct kgdb_io *` called `dbg_io_ops`. It's initialized in `debug_core.c` and checked throughout the debug flow. There's a null check in `kdb_msg_write` which triggers static analyzers and gives the (almost entirely wrong) impression that it can be null. Coverity scanner caught this as CID 1465042. I have removed the unnecessary null check and eliminated false-positive forward null dereference warning. Signed-off-by: Cengiz Can --- kernel/debug/kdb/kdb_io.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 683a799618ad..4ac59a4fbeec 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -549,14 +549,12 @@ static void kdb_msg_write(const char *msg, int msg_len) if (msg_len == 0) return; - if (dbg_io_ops) { - const char *cp = msg; - int len = msg_len; + const char *cp = msg; + int len = msg_len; - while (len--) { - dbg_io_ops->write_char(*cp); - cp++; - } + while (len--) { + dbg_io_ops->write_char(*cp); + cp++; } for_each_console(c) { -- 2.27.0