From patchwork Tue Mar 15 21:45:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 102563 Delivered-To: patch@linaro.org Received: by 10.112.199.169 with SMTP id jl9csp936170lbc; Tue, 15 Mar 2016 14:45:53 -0700 (PDT) X-Received: by 10.67.21.167 with SMTP id hl7mr508646pad.16.1458078353289; Tue, 15 Mar 2016 14:45:53 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id w1si243112par.40.2016.03.15.14.45.53; Tue, 15 Mar 2016 14:45:53 -0700 (PDT) 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 S932950AbcCOVpu (ORCPT + 31 others); Tue, 15 Mar 2016 17:45:50 -0400 Received: from mout.kundenserver.de ([212.227.126.187]:61555 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751968AbcCOVpq (ORCPT ); Tue, 15 Mar 2016 17:45:46 -0400 Received: from wuerfel.lan. ([78.42.132.4]) by mrelayeu.kundenserver.de (mreue001) with ESMTPA (Nemesis) id 0MeGZ4-1aSILw1phm-00PvUk; Tue, 15 Mar 2016 22:45:42 +0100 From: Arnd Bergmann To: Maxim Levitsky Cc: Arnd Bergmann , Andrew Morton , Quentin Lambert , linux-kernel@vger.kernel.org Subject: [PATCH] memstick: r592: avoid gcc-6 warning Date: Tue, 15 Mar 2016 22:45:22 +0100 Message-Id: <1458078336-602226-1-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 2.7.0 X-Provags-ID: V03:K0:UUTFL/0hLlED2jB72xo30TbqynB9JEJED1ByBYtdO1Ntf+tSbkk SSQsXWUledbRvpLacHZdyhra6STuYoV17PbWei3DqOYVc/YoP/1lOn7DiGAwdbRoHeWVy+r sdnsCluMizkvKgmGWJWwxoEbfUws6FKYtqDKy+ivatrn65cUmosqaL1qjBJntteL8yi6cMj yode73xGEvQODu3gLeRCA== X-UI-Out-Filterresults: notjunk:1; V01:K0:LWZ4V5U6fCQ=:6o00G5SfrO0fV+xALyDmW3 uuHz6tEFOJvj2Hq5rgWMbWZBDHd5bzDKGrjDK9fruSpnEYcJ+x9JWM70GW0v4BywSBctw8Vic WTGPjoZlYYnHS1U3gsfgdroTNz/+VlRJboV2I0osSOenOXsyQkYjwHUdNfzR0JQYKMIv0Vc+c QG6c2hBEhZl5VZ0MDWO1DD9n7Dm/skgQp1a1OoAMQ/zG8KTcSg5ym4ktWmIOyK0X6PqkQQlIP 58rNxZBeWXSQ4O9VtwuXmHU3nuhvtmAMvZM2v2yEOzwSHKluDTolWRZspO81CdZ2WN9ldite0 QGV7MpxOV3iKWyupEbbQwGNyK1U2ZPIkAWTVS32e83nKdF8AmdGpSVQZF1ZvxTTKPoKkQomBm s8ZdIsDzchtByeijpTov12dfgYa5OLZ9Ct9jWH1ef3YpJQ558v9TGvLePsnmOUcn/r++R0xE5 BOuZEpRQicuyYwjTrueRBZxmIAVNXv5S3LpDr4syWZoIMyWdzKgjAUXF8bFiX4c+BCdawuhoB ovtf9VofIMnp60s24lkdq3pvhvi2da6XEROJog8iFfeNYtVEeqrIKuxHmVDMdbWgO44wID/e9 SDV61e0SfN7cyXvNwopx9Ph/Qk0fv15WERZ2YVBvg8Ti0J6ZOH3IDOa4mKf3jRoVUuCgjK0yj 8v2Dx6R6kJPP/+sMy8tzma/JKazSJpBo5Cl8LtdUwx0BG+fAOD1M/WwQw9xY4ZTPs0uA= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The r592 driver relies on behavior of the DMA mapping API that is normally observed but not guaranteed by the API. Instead it uses a runtime check to fail transfers if the API ever behaves differently. When CONFIG_NEED_SG_DMA_LENGTH is not set, one of the checks turns into a comparison of a variable with itself, which gcc-6.0 now warns about: drivers/memstick/host/r592.c: In function 'r592_transfer_fifo_dma': drivers/memstick/host/r592.c:302:31: error: self-comparison always evaluates to false [-Werror=tautological-compare] (sg_dma_len(&dev->req->sg) < dev->req->sg.length)) { ^ The check itself is not a problem, so this patch just rephrases the condition in a way that gcc does not consider an indication of a mistake. We already know that dev->req->sg.length was initially R592_LFIFO_SIZE, so we can compare it to that constant again. Signed-off-by: Arnd Bergmann --- drivers/memstick/host/r592.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.7.0 diff --git a/drivers/memstick/host/r592.c b/drivers/memstick/host/r592.c index ef09ba0289d7..d5cfb503b9d6 100644 --- a/drivers/memstick/host/r592.c +++ b/drivers/memstick/host/r592.c @@ -298,8 +298,7 @@ static int r592_transfer_fifo_dma(struct r592_device *dev) sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ? PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE); - if (sg_count != 1 || - (sg_dma_len(&dev->req->sg) < dev->req->sg.length)) { + if (sg_count != 1 || sg_dma_len(&dev->req->sg) < R592_LFIFO_SIZE) { message("problem in dma_map_sg"); return -EIO; }