Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750923AbVLTWyE (ORCPT ); Tue, 20 Dec 2005 17:54:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750995AbVLTWyE (ORCPT ); Tue, 20 Dec 2005 17:54:04 -0500 Received: from H190.C26.B96.tor.eicat.ca ([66.96.26.190]:46483 "EHLO moraine.clusterfs.com") by vger.kernel.org with ESMTP id S1750923AbVLTWyC (ORCPT ); Tue, 20 Dec 2005 17:54:02 -0500 From: Nikita Danilov MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <17320.35736.89250.390950@gargle.gargle.HOWL> Date: Wed, 21 Dec 2005 01:54:16 +0300 To: "linux-os (Dick Johnson)" Cc: "Mike Snitzer" , "Adrian Bunk" , "Mark Lord" , "J.A. Magallon" , "Linux-Kernel," , , Subject: Re: About 4k kernel stack size.... Newsgroups: gmane.linux.kernel In-Reply-To: References: <20051218231401.6ded8de2@werewolf.auna.net> <43A77205.2040306@rtr.ca> <20051220133729.GC6789@stusta.de> <170fa0d20512200637l169654c9vbe38c9931c23dfb1@mail.gmail.com> <46578.10.10.10.28.1135094132.squirrel@linux1> X-Mailer: VM 7.17 under 21.5 (patch 17) "chayote" (+CVS-20040321) XEmacs Lucid Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1294 Lines: 37 linux-os \(Dick Johnson\) writes: > [...] > See, isn't rule-making fun? This whole 4k stack- > thing is really dumb. Other operating systems > use paged virtual memory for stacks, except > for the interrupt stack. If Linux used paged > virtual memory for stacks, ... then spin-locks couldn't be held across function calls. > the pages would not > have to be contiguous so dynamic stack allocation > would practically never fail. But Linux doesn't > use paged virtual memory for stacks. So, there > needs to be some rule to control the amount > of kernel stack allocated to each task when it > executes a system call. > > This means, in the limit, that there are two > possibilities: > > (1) Implement paged virtual memory for stack. As an exercise: subscribe to NT kernel development mailing list, and see the fun they have when page-in code trips over paged out kernel text page. As a rule, even code cannot pageable without very involving and fragile analysis. Not to say about stack. Nikita. - 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/