From owner-freebsd-current@FreeBSD.ORG Fri Aug 1 16:01:59 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1ACAD37B401; Fri, 1 Aug 2003 16:01:59 -0700 (PDT) Received: from ns1.xcllnt.net (209-128-86-226.BAYAREA.NET [209.128.86.226]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1B48743FBD; Fri, 1 Aug 2003 16:01:58 -0700 (PDT) (envelope-from marcel@xcllnt.net) Received: from dhcp01.pn.xcllnt.net (dhcp01.pn.xcllnt.net [192.168.4.201]) by ns1.xcllnt.net (8.12.9/8.12.9) with ESMTP id h71N1vwO004938; Fri, 1 Aug 2003 16:01:57 -0700 (PDT) (envelope-from marcel@piii.pn.xcllnt.net) Received: from dhcp01.pn.xcllnt.net (localhost [127.0.0.1]) by dhcp01.pn.xcllnt.net (8.12.9/8.12.9) with ESMTP id h71N1vA5006376; Fri, 1 Aug 2003 16:01:57 -0700 (PDT) (envelope-from marcel@dhcp01.pn.xcllnt.net) Received: (from marcel@localhost) by dhcp01.pn.xcllnt.net (8.12.9/8.12.9/Submit) id h71N1vb7006375; Fri, 1 Aug 2003 16:01:57 -0700 (PDT) (envelope-from marcel) Date: Fri, 1 Aug 2003 16:01:57 -0700 From: Marcel Moolenaar To: deischen@freebsd.org Message-ID: <20030801230157.GA6323@dhcp01.pn.xcllnt.net> References: <200308020647.18039.davidxu@FreeBSD.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.4i cc: David Xu cc: current@freebsd.org Subject: Re: NVidia glx stuff dies in sysarch(I386_SET_LDT, ...) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Aug 2003 23:01:59 -0000 On Fri, Aug 01, 2003 at 06:51:33PM -0400, Daniel Eischen wrote: > > LUCODE_SEL is used by kernel to load _ucodesel to user %cs > > LUDATA_SEL is used by kernel to load _udatasel to user %ds, %es, %fs, %gs. > > I didn't check other ABIs, but setting to a fixed location of LDT in userland > > is also a bad idea, I think it will conflict with thread library soon, > > it is better to use dynamic allocating facility newly added in i386_set_ldt. > > Perhaps we need to rethink the interface and disallow > specification of any ldt; only allow dynamic. We would > need a different method of setting an array of them, though. Why not allow setting a specific entry when it's currently unused and not reserved by us? We can simply fail if the process is trying to set a LDT entry that's currently being used or is reserved by us. The only case that causes problems is when an existing LDT entry is overwritten by another consumer. -- Marcel Moolenaar USPA: A-39004 marcel@xcllnt.net