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=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 B9606C33CAF for ; Thu, 16 Jan 2020 17:38:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8FDDB246EF for ; Thu, 16 Jan 2020 17:38:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196293; bh=QNGO+4h+4tv4Cjbm89Vwy1rtiuhXMwGt9Ox0SnAPSOc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=r/xcahvbVft25rL+5vJbYzYlyoD4c8qc9abcaJEbIEifM/TZp3MF3C04dApwAYzxH Ls+nkalqA3j/hVHJdvtaKt/euEVYVbsx9IQHAa96yEgUtVs7EdNtpMYsUTp4e0aI/O FsK4f/IwxP2vRP2BLZrgtO+SOg4iwt0/Yk2osFfo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393299AbgAPRiM (ORCPT ); Thu, 16 Jan 2020 12:38:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:53934 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389965AbgAPRiL (ORCPT ); Thu, 16 Jan 2020 12:38:11 -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 8E05A246C3; Thu, 16 Jan 2020 17:38:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196290; bh=QNGO+4h+4tv4Cjbm89Vwy1rtiuhXMwGt9Ox0SnAPSOc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QK1imqXp+k9/9NFVCgciT3I0li/54tXXNxYkhYQzTAslzhyvoXo3xqjFcLsDui5of XMQu87GL/MfAFQ+xvY8+NDF0wFfBhTPtI8xtQD+pSNub8TNLoBoigjKb4yhCgl2QPI ZyGO0FDrPkJeuAUHfQ+FxhrKx6EH4Et7yoDLvC7I= 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 4.9 105/251] media: davinci-isif: avoid uninitialized variable use Date: Thu, 16 Jan 2020 12:34:14 -0500 Message-Id: <20200116173641.22137-65-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116173641.22137-1-sashal@kernel.org> References: <20200116173641.22137-1-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