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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 99E60C33CAF for ; Thu, 16 Jan 2020 19:03:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 73EFF2075B for ; Thu, 16 Jan 2020 19:03:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579201412; bh=qYzyfsKwX5P/PuWJpfC14glwxT+idLXapD5N8g1prvE=; h=From:To:Cc:Subject:Date:List-ID:From; b=aFBaK6204FJlDX71cdHwRuXUTM7mcloLKTSpErPxv5FU8vv0l/vTV9Q6SiE0LcPmT 6qgv9zcMSuydDYvl5Vr2hyuDdR6VP+6rTE5mLp1HRzIPZVVjsg+t14hPnfhll3rmJS ix/K50VUPYuxD+keITAxLzhOGm6DV86sB0LkPPwo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437340AbgAPTDa (ORCPT ); Thu, 16 Jan 2020 14:03:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:33560 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387697AbgAPRFM (ORCPT ); Thu, 16 Jan 2020 12:05:12 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C9B522077B; Thu, 16 Jan 2020 17:05:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194311; bh=qYzyfsKwX5P/PuWJpfC14glwxT+idLXapD5N8g1prvE=; h=From:To:Cc:Subject:Date:From; b=ND1YA85D+Ir14Xc2EjSui0jo0qJr4xassAjsjhWKhmaagrUocLAqVI42WqgXpN6uV wXLrM4zQVsN5HkkmvEWwNUhtKAUDKWNQgfogMxaR1FMw3ZdH9PNggP3PgVwoDIHOCA G6Xj4ncZ+0C98nBbGaPajzSxGfk4qj6Fz3kjgI/o= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arnd Bergmann , Nathan Chancellor , Lad Prabhakar , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org, clang-built-linux@googlegroups.com Subject: [PATCH AUTOSEL 4.19 264/671] media: davinci-isif: avoid uninitialized variable use Date: Thu, 16 Jan 2020 11:58:22 -0500 Message-Id: <20200116170509.12787-1-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann [ Upstream commit 0e633f97162c1c74c68e2eb20bbd9259dce87cd9 ] clang warns about a possible variable use that gcc never complained about: drivers/media/platform/davinci/isif.c:982:32: error: variable 'frame_size' is uninitialized when used here [-Werror,-Wuninitialized] dm365_vpss_set_pg_frame_size(frame_size); ^~~~~~~~~~ drivers/media/platform/davinci/isif.c:887:2: note: variable 'frame_size' is declared here struct vpss_pg_frame_size frame_size; ^ 1 error generated. There is no initialization for this variable at all, and there has never been one in the mainline kernel, so we really should not put that stack data into an mmio register. On the other hand, I suspect that gcc checks the condition more closely and notices that the global isif_cfg.bayer.config_params.test_pat_gen flag is initialized to zero and never written to from any code path, so anything depending on it can be eliminated. To shut up the clang warning, just remove the dead code manually, it has probably never been used because any attempt to do so would have resulted in undefined behavior. Fixes: 63e3ab142fa3 ("V4L/DVB: V4L - vpfe capture - source for ISIF driver on DM365") Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Acked-by: Lad Prabhakar Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/platform/davinci/isif.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/drivers/media/platform/davinci/isif.c b/drivers/media/platform/davinci/isif.c index 340f8218f54d..80fa60a4c448 100644 --- a/drivers/media/platform/davinci/isif.c +++ b/drivers/media/platform/davinci/isif.c @@ -884,9 +884,7 @@ static int isif_set_hw_if_params(struct vpfe_hw_if_param *params) static int isif_config_ycbcr(void) { struct isif_ycbcr_config *params = &isif_cfg.ycbcr; - struct vpss_pg_frame_size frame_size; u32 modeset = 0, ccdcfg = 0; - struct vpss_sync_pol sync; dev_dbg(isif_cfg.dev, "\nStarting isif_config_ycbcr..."); @@ -974,13 +972,6 @@ static int isif_config_ycbcr(void) /* two fields are interleaved in memory */ regw(0x00000249, SDOFST); - /* Setup test pattern if enabled */ - if (isif_cfg.bayer.config_params.test_pat_gen) { - sync.ccdpg_hdpol = params->hd_pol; - sync.ccdpg_vdpol = params->vd_pol; - dm365_vpss_set_sync_pol(sync); - dm365_vpss_set_pg_frame_size(frame_size); - } return 0; } -- 2.20.1