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 60C13C33CAF for ; Thu, 16 Jan 2020 17:55:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D20C2469B for ; Thu, 16 Jan 2020 17:55:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579197319; bh=QNGO+4h+4tv4Cjbm89Vwy1rtiuhXMwGt9Ox0SnAPSOc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=M+sVU3ADdjpiDHPYGIcQWk6MmEJz0lrcbRuEWjebJ/aLZ+l/rro9ATFbzU7mrzvD1 pBFby3OznWBvgb4r3PGnfgi1909vqvl4PvS1I69KTiTg2vZfI7iZG1Ntp6NdWbKDlE rhKQrC5o5BbnnTBL5nzzWfA/03WfPF/aBC1P6y7o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394136AbgAPRoZ (ORCPT ); Thu, 16 Jan 2020 12:44:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:35354 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394153AbgAPRoY (ORCPT ); Thu, 16 Jan 2020 12:44:24 -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 CC21024750; Thu, 16 Jan 2020 17:44:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196663; bh=QNGO+4h+4tv4Cjbm89Vwy1rtiuhXMwGt9Ox0SnAPSOc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z/Obe6hgf0kMEtmA1Qq10eM7OnjpG3ehpWp++U9la6pa3toGzjDSuXKbPWXFtbYhV etGGdw0BVJSOBNZTwZI8BjfKs7Q9ofrxA5Ef5zWrfL7lOrKN8Veasf1nL3lXR/KQYb e+Qt/OMU2Kn5bdmuAmmB+PxQ0m0NiOZUHPO7pq2o= 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 4.4 066/174] media: davinci-isif: avoid uninitialized variable use Date: Thu, 16 Jan 2020 12:41:03 -0500 Message-Id: <20200116174251.24326-66-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116174251.24326-1-sashal@kernel.org> References: <20200116174251.24326-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@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 78e37cf3470f..b51b875c5a61 100644 --- a/drivers/media/platform/davinci/isif.c +++ b/drivers/media/platform/davinci/isif.c @@ -890,9 +890,7 @@ 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..."); @@ -980,13 +978,6 @@ 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