Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932098AbWCSN3X (ORCPT ); Sun, 19 Mar 2006 08:29:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932095AbWCSN3X (ORCPT ); Sun, 19 Mar 2006 08:29:23 -0500 Received: from mail1.kontent.de ([81.88.34.36]:5314 "EHLO Mail1.KONTENT.De") by vger.kernel.org with ESMTP id S932092AbWCSN3W convert rfc822-to-8bit (ORCPT ); Sun, 19 Mar 2006 08:29:22 -0500 From: Oliver Neukum To: Arjan van de Ven Subject: Re: [PATCH]use kzalloc in vfs where appropriate Date: Sun, 19 Mar 2006 14:29:21 +0100 User-Agent: KMail/1.8 Cc: Matthew Wilcox , viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org References: <200603181144.10820.oliver@neukum.org> <1142679326.2889.20.camel@laptopd505.fenrus.org> In-Reply-To: <1142679326.2889.20.camel@laptopd505.fenrus.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Content-Disposition: inline Message-Id: <200603191429.21776.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1369 Lines: 38 Am Samstag, 18. März 2006 11:55 schrieb Arjan van de Ven: > On Sat, 2006-03-18 at 11:44 +0100, Oliver Neukum wrote: > > Am Freitag, 17. März 2006 22:08 schrieb Matthew Wilcox: > > > On Fri, Mar 17, 2006 at 09:58:14PM +0100, Oliver Neukum wrote: > > > > --- a/fs/bio.c 2006-03-11 23:12:55.000000000 +0100 > > > > +++ b/fs/bio.c 2006-03-17 16:44:49.000000000 +0100 > > > > @@ -635,12 +635,10 @@ > > > > return ERR_PTR(-ENOMEM); > > > > > > > > ret = -ENOMEM; > > > > - pages = kmalloc(nr_pages * sizeof(struct page *), GFP_KERNEL); > > > > + pages = kzalloc(nr_pages * sizeof(struct page *), GFP_KERNEL); > > > > > > Didn't we just discuss this one and conclude it needed to use kcalloc > > > instead? > > > > I've found some discussion in the archive, but no conclusion. Could you > > elaborate? > > kcalloc is the array allocator. > Here.. you're allocating an array of nr_pages worth of pointers. > kcalloc does extra checks because it KNOWS it's an array... I see. A patch is coming. Shouldn't this check from slab.h: if (n != 0 && size > INT_MAX / n) return NULL; carry an "unlikely"? Regards Oliver - 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/