From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756382AbaE2VDk (ORCPT ); Thu, 29 May 2014 17:03:40 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:44898 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754147AbaE2VDj (ORCPT ); Thu, 29 May 2014 17:03:39 -0400 Date: Thu, 29 May 2014 14:03:37 -0700 From: Andrew Morton To: Rickard Strandqvist Cc: Mark Fasheh , Joel Becker , ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] fs: ocfs2: move_extents.c: Fix to remove null pointer checks that could never happen Message-Id: <20140529140337.f999bfaaf9ffabce071962ea@linux-foundation.org> In-Reply-To: <1401222231-21656-1-git-send-email-rickard_strandqvist@spectrumdigital.se> References: <1401222231-21656-1-git-send-email-rickard_strandqvist@spectrumdigital.se> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 27 May 2014 22:23:51 +0200 Rickard Strandqvist wrote: > Removal of null pointer checks that could never happen How do you know it never happens? > --- a/fs/ocfs2/move_extents.c > +++ b/fs/ocfs2/move_extents.c > @@ -904,9 +904,6 @@ static int ocfs2_move_extents(struct ocfs2_move_extents_context *context) > struct buffer_head *di_bh = NULL; > struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); > > - if (!inode) > - return -ENOENT; > - If it's due to assuming that the previous statement would have oopsed then that is mistaken. Is is sometimes the case that gcc will move the evaluation of inode->i_sb to after the test, so this function can be passed NULL and it will not oops.