Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933241AbbBDMlq (ORCPT ); Wed, 4 Feb 2015 07:41:46 -0500 Received: from mail-ie0-f180.google.com ([209.85.223.180]:60110 "EHLO mail-ie0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964860AbbBDMlg (ORCPT ); Wed, 4 Feb 2015 07:41:36 -0500 Message-ID: <1423053695.907.117.camel@edumazet-glaptop2.roam.corp.google.com> Subject: Re: [PATCH] net: core/dev: fix sparse warning From: Eric Dumazet To: Lad Prabhakar Cc: "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Dumazet Date: Wed, 04 Feb 2015 04:41:35 -0800 In-Reply-To: <1423052746-3688-1-git-send-email-prabhakar.csengg@gmail.com> References: <1423052746-3688-1-git-send-email-prabhakar.csengg@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2740 Lines: 72 On Wed, 2015-02-04 at 12:25 +0000, Lad Prabhakar wrote: > From: "Lad, Prabhakar" > > this patch fixes following sparse warning: > net/core/dev.c: In function 'validate_xmit_skb_list': > net/core/dev.c:2720: warning: 'tail' may be used uninitialized in this function > > Although its a false positive, as head is assigned to NULL in the > beginning, due which later in the loop tail is assigned to skb->prev. > > Signed-off-by: Lad, Prabhakar > --- > net/core/dev.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/dev.c b/net/core/dev.c > index 8ce0d1a..c736467 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -2717,7 +2717,7 @@ out_null: > > struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev) > { > - struct sk_buff *next, *head = NULL, *tail; > + struct sk_buff *next, *head = NULL, *tail = NULL; > > for (; skb != NULL; skb = next) { > next = skb->next; Which gcc/sparse versions are you using ? I do not see this warning here. $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.8.2-19ubuntu1' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs --enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.8 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --disable-libmudflap --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.8-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1) $ sparse --version 0.4.5-rc1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/