From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264161AbTEGSX4 (ORCPT ); Wed, 7 May 2003 14:23:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264160AbTEGSX4 (ORCPT ); Wed, 7 May 2003 14:23:56 -0400 Received: from neon-gw-l3.transmeta.com ([63.209.4.196]:30227 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id S264161AbTEGSXy (ORCPT ); Wed, 7 May 2003 14:23:54 -0400 To: linux-kernel@vger.kernel.org From: torvalds@transmeta.com (Linus Torvalds) Subject: Re: top stack (l)users for 2.5.69 Date: 7 May 2003 18:36:06 GMT Organization: Transmeta Corp Message-ID: <1052332566.752437@palladium.transmeta.com> References: <20030507132024.GB18177@wohnheim.fh-wedel.de> X-Trace: palladium.transmeta.com 1052332566 4508 127.0.0.1 (7 May 2003 18:36:06 GMT) X-Complaints-To: news@transmeta.com NNTP-Posting-Date: 7 May 2003 18:36:06 GMT X-Newsreader: trn 4.0-test76 (Apr 2, 2001) Originator: torvalds@penguin.transmeta.com (Linus Torvalds) Cache-Post-Path: palladium.transmeta.com!unknown@penguin.transmeta.com X-Cache: nntpcache 2.4.0b5 (see http://www.nntpcache.org/) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In article , Richard B. Johnson wrote: > >You know (I hope) that allocating stuff on the stack is not >"bad". Allocating stuff on the stack _is_ bad if you allocate more than a few hundred bytes. That's _especially_ true deep down in the call-sequence, ie in device drivers, low-level filesystems etc. The kernel stack is a very limited resource, with no protection from overflow. Being lazy and using automatic variables is a BAD BAD thing, even if it's syntactically easy and generates good code. Linus