From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755203Ab0I1WPw (ORCPT ); Tue, 28 Sep 2010 18:15:52 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:48291 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754555Ab0I1WPv (ORCPT ); Tue, 28 Sep 2010 18:15:51 -0400 Date: Tue, 28 Sep 2010 23:15:46 +0100 From: Al Viro To: Andrew Morton Cc: Namhyung Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: cleanup gfp_zone() Message-ID: <20100928221546.GI19804@ZenIV.linux.org.uk> References: <1285676624-1300-1-git-send-email-namhyung@gmail.com> <20100928143239.5fe34e1e.akpm@linux-foundation.org> <20100928214141.GG19804@ZenIV.linux.org.uk> <20100928144518.0eaf1099.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100928144518.0eaf1099.akpm@linux-foundation.org> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 28, 2010 at 02:45:18PM -0700, Andrew Morton wrote: > On Tue, 28 Sep 2010 22:41:42 +0100 > > > hm. I hope these sparse warnings are sufficiently useful to justify > > > all the gunk we're adding to support them. > > > > > > Is it actually finding any bugs? > > > > FWIW, bitwise or done in the right-hand argumet of shift looks ugly as hell; > > what the hell is that code _doing_? > > There's a nice fat comment a few lines up... [snip] Egads... IMO the cleanest way to deal with that is to add integer constants, not to be used anywhere else (e.g. ___GFP_DMA, with #define __GFP_DMA ((__force gfp_t)___GFP_DMA) and use them in that horror. As for the gfp_t warnings - yes, they'd caught a bunch of bugs at some point; considering the bitrot rates... might be worth rechecking.