From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Sat, 29 Jan 2005 00:03:07 +0000 (GMT) Received: from p3EE07947.dip.t-dialin.net ([IPv6:::ffff:62.224.121.71]:26215 "EHLO mail.linux-mips.net") by linux-mips.org with ESMTP id ; Sat, 29 Jan 2005 00:02:52 +0000 Received: from fluff.linux-mips.net (localhost.localdomain [127.0.0.1]) by mail.linux-mips.net (8.13.1/8.13.1) with ESMTP id j0T02jE5011800; Sat, 29 Jan 2005 01:02:45 +0100 Received: (from ralf@localhost) by fluff.linux-mips.net (8.13.1/8.13.1/Submit) id j0T02Zpi011799; Sat, 29 Jan 2005 01:02:35 +0100 Date: Sat, 29 Jan 2005 01:02:35 +0100 From: Ralf Baechle To: David Daney Cc: zhan rongkai , linux-mips@linux-mips.org Subject: Re: Why does MIPS/Linux always reserve 32 bytes in the top of each process's kernel stack space Message-ID: <20050129000235.GA11602@linux-mips.org> References: <69397FFCADEFD94F8D5A0FC0FDBCBBDEF53B@avtrex-server.hq.avtrex.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <69397FFCADEFD94F8D5A0FC0FDBCBBDEF53B@avtrex-server.hq.avtrex.com> User-Agent: Mutt/1.4.1i Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 7065 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Thu, Jan 27, 2005 at 08:54:48PM -0800, David Daney wrote: > >Why does MIPS/Linux always reserve 32 bytes in the top of each > >process's kernel stack space. > > Perhaps because the kernel's ABI requires it? I beleive that o64 requires stack space for a0 - a3 to be stored there. Except we don't use o64. Ralf