From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756801Ab2KVVK7 (ORCPT ); Thu, 22 Nov 2012 16:10:59 -0500 Received: from mail-pa0-f46.google.com ([209.85.220.46]:50895 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751706Ab2KVVKz (ORCPT ); Thu, 22 Nov 2012 16:10:55 -0500 Date: Wed, 21 Nov 2012 15:00:57 -0800 From: Greg KH To: Jiri Slaby Cc: Sachin Kamat , linux-kernel@vger.kernel.org, patches@linaro.org Subject: Re: [PATCH 1/1] tty: vt: Remove redundant null check before kfree. Message-ID: <20121121230057.GA29095@kroah.com> References: <1353475147-28308-1-git-send-email-sachin.kamat@linaro.org> <20121121144624.GA21766@kroah.com> <50AD5916.3030604@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50AD5916.3030604@suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 21, 2012 at 11:43:34PM +0100, Jiri Slaby wrote: > On 11/21/2012 03:46 PM, Greg KH wrote: > > On Wed, Nov 21, 2012 at 10:49:07AM +0530, Sachin Kamat wrote: > >> --- a/drivers/tty/vt/consolemap.c > >> +++ b/drivers/tty/vt/consolemap.c > >> @@ -410,10 +410,8 @@ static void con_release_unimap(struct uni_pagedir *p) > >> kfree(p->inverse_translations[i]); > >> p->inverse_translations[i] = NULL; > >> } > >> - if (p->inverse_trans_unicode) { > >> - kfree(p->inverse_trans_unicode); > >> - p->inverse_trans_unicode = NULL; > >> - } > >> + kfree(p->inverse_trans_unicode); > >> + p->inverse_trans_unicode = NULL; > > > > kfree with NULL is a no-op, but the line after that just caused a kernel > > crash if it was NULL, so I can't accept this type of thing. > > Greg, I'm not sure -- what do you mean here? The change actually looks > fine to me... We do not dereference p->inverse_trans_unicode there. If we never dereference it, why is it being set to NULL? greg k-h