From patchwork Thu Nov 30 11:08:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 120135 Delivered-To: patch@linaro.org Received: by 10.140.22.227 with SMTP id 90csp522689qgn; Thu, 30 Nov 2017 03:10:08 -0800 (PST) X-Google-Smtp-Source: AGs4zMasd0Sn8qvqmKesmuaGEObkeWRTFfFeTuQ04UvdOH43Pc8IMR/lmukRjLxKYkgS+3/lg3kc X-Received: by 10.99.182.2 with SMTP id j2mr2059465pgf.116.1512040208830; Thu, 30 Nov 2017 03:10:08 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1512040208; cv=none; d=google.com; s=arc-20160816; b=WvhxklozwAkrE+YHk+Kds2WIeNF2P8K7PmEevs3yV00MIjvZbpQtfDmeVdi+3BAjDG ueWf/vwDTLH4Qi94C6PZ8k6bINK77lop8hjBrb7IE3vIsbTQH25cLAj1QydKkukRm+EG D2mHsi1QHPdkpLmlAHbnuH+AZ0hVMqqFPEUAxsHTI9kjBOypYClr/R97+LOSCSbxpidD iSfHhK9W4s/WyNWn+BVUMBnXt1ZcWWaxk4aJO7ivpcoFebHZbChRrf8oT+xUAjqmAeoE 4GBGlm0z/SUSzbnizFOB603FCkHwmizfhI6JURkJ4mTAnkgLT3tYD41pq0LKMQrlefJo Xk2A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=w2axbrVFRIuPdSh6Hse1JVaAcNjqQWsdy8VQ/7kxWFs=; b=Axyhf6ZeVnz17oeyirX8IxEzb+nRyTjbjh5atIyMvcQxtBTUPZ7YJe+8eZ6F6l//dp fnLroWkTDDjPs5g7gY8JigfxjO+4GBlAz1yk7GNpDu5WBT8tO5KbGwnjxIpBUDeub5At W/Dyaard7nzqJdYbh+2w7tnn5pfKsLPG6zHwTtGXZoKw+5y6XifUeXW4fPmHhey72O3k 3avaTU/CJZaL6AkoUO5MER1EeFeyyCkBuOkL8ItMsoSynfflqu/yK/oGLB5oW61v7cIL +AfAQCHH2b+c7mHzBEJr8C3mAXbt2hRbQsLR/dQL2yI9tcUzYOBUdItSESCAIKk6By7v oFyA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o10si2847691pge.179.2017.11.30.03.10.08; Thu, 30 Nov 2017 03:10:08 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751850AbdK3LKH (ORCPT + 26 others); Thu, 30 Nov 2017 06:10:07 -0500 Received: from mout.kundenserver.de ([212.227.126.187]:56146 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750771AbdK3LKF (ORCPT ); Thu, 30 Nov 2017 06:10:05 -0500 Received: from wuerfel.lan ([109.193.157.232]) by mrelayeu.kundenserver.de (mreue002 [212.227.15.129]) with ESMTPA (Nemesis) id 0MDHpc-1eLS8S3VzI-00Gb8p; Thu, 30 Nov 2017 12:10:00 +0100 From: Arnd Bergmann To: Mauro Carvalho Chehab Cc: Arnd Bergmann , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH, RESEND 2/2] r820t: fix r820t_write_reg for KASAN Date: Thu, 30 Nov 2017 12:08:05 +0100 Message-Id: <20171130110939.1140969-2-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 In-Reply-To: <20171130110939.1140969-1-arnd@arndb.de> References: <20171130110939.1140969-1-arnd@arndb.de> X-Provags-ID: V03:K0:Tzb1FToCWC8G4t4rf+YqzmTwvcDZ69nPXSv5nmTAqpYWGY+wgOT h5N79c2SQ1FHkHYBH/wM965ISfg8n6G2xgyhT0iV81TsGSR934JeA2ozDtGEjwV3r3cYv76 3MKaTGqRzOoj08yDwN2tmyipH7/PUtbUXNdxMWdW/2O0ucm3FLyYesFfDlPtXU+lEi7K4Qh NWdaNbnQmDkENJrpXZDOA== X-UI-Out-Filterresults: notjunk:1; V01:K0:ccrSvec2jVo=:RwoW8MFnEzHGHGFCl+GEZN z6DkoGRixIz5tjnZIctodEDx0iV31ckvKRX69dbGFuV0RkX/pRV1klxvRm9B0h0HpoQlzDrHN tNtMQH/41FX7H3fmt6tQnfYaInEUhM2lid07FISgQSF+sIZ4QTbmls61daawgFNgAlxZq6V7i G4TpqMokOHIp8PKwyFXEpzPAmRppmX42hk0+nxqG2+hOaHkW8EbJmXnpVFvYDzKuM8LGf72+e cTjKdufcS/8Hb5O40uiRWi5M75lWtM6S+OZVqTCU/lHWQ6v9mY6LXb9OrqeXr9SIcyxjzQoeT z7t2K1S70gG6pJvL3BQODtukEqks6ZYA9ykZ9LwCiJjDdAx3hxjNP+SJhXkt9PRGUh3oBzoja QM9OPQ/57K3WE5uXvzSY7k5Ei6K5Sxn9aFdtpOQr492cLtH5dhsoAc53ndS9hobHRsHf36jW2 /SDLo+fPGuR8DtNCbyx+77kUjfpUx6zUTfD9o9nxxu0Oh8q6X5K1zEKkJDCMkMQkSZvrjujwM fsvJKSD/JsUL8OGOtZII3sTY0a5qCIREmtbM3Zy4y/SroVix9xd1xfNmBI6FdCPj+qfBpR74n 3OzGRnQ7myM1U4Vu9nc3XQCwOiD1IDAiI/KRMiS3CW26hSBlk5Mnxr//pc1f0pg1wDXoc6dX2 1XfpNTqzv2FRd6i0J7d3tEJuQ93tAJXDABfpS3xB/vejT6Co3j3L4eCvn+VyV46s/8V+nMFUK UnzCSPXnzmRVxDj18eO6yKFsW0sQAsaBYJ8DXQ== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With CONFIG_KASAN, we get an overly long stack frame due to inlining the register access functions: drivers/media/tuners/r820t.c: In function 'generic_set_freq.isra.7': drivers/media/tuners/r820t.c:1334:1: error: the frame size of 2880 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] This is caused by a gcc bug that has now been fixed in gcc-8. To work around the problem, we can pass the register data through a local variable that older gcc versions can optimize out as well. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 Signed-off-by: Arnd Bergmann --- drivers/media/tuners/r820t.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) -- 2.9.0 diff --git a/drivers/media/tuners/r820t.c b/drivers/media/tuners/r820t.c index ba80376a3b86..d097eb04a0e9 100644 --- a/drivers/media/tuners/r820t.c +++ b/drivers/media/tuners/r820t.c @@ -396,9 +396,11 @@ static int r820t_write(struct r820t_priv *priv, u8 reg, const u8 *val, return 0; } -static int r820t_write_reg(struct r820t_priv *priv, u8 reg, u8 val) +static inline int r820t_write_reg(struct r820t_priv *priv, u8 reg, u8 val) { - return r820t_write(priv, reg, &val, 1); + u8 tmp = val; /* work around GCC PR81715 with asan-stack=1 */ + + return r820t_write(priv, reg, &tmp, 1); } static int r820t_read_cache_reg(struct r820t_priv *priv, int reg) @@ -411,17 +413,18 @@ static int r820t_read_cache_reg(struct r820t_priv *priv, int reg) return -EINVAL; } -static int r820t_write_reg_mask(struct r820t_priv *priv, u8 reg, u8 val, +static inline int r820t_write_reg_mask(struct r820t_priv *priv, u8 reg, u8 val, u8 bit_mask) { + u8 tmp = val; int rc = r820t_read_cache_reg(priv, reg); if (rc < 0) return rc; - val = (rc & ~bit_mask) | (val & bit_mask); + tmp = (rc & ~bit_mask) | (tmp & bit_mask); - return r820t_write(priv, reg, &val, 1); + return r820t_write(priv, reg, &tmp, 1); } static int r820t_read(struct r820t_priv *priv, u8 reg, u8 *val, int len)