From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265105AbUELPem (ORCPT ); Wed, 12 May 2004 11:34:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265111AbUELPem (ORCPT ); Wed, 12 May 2004 11:34:42 -0400 Received: from cpe-24-221-190-179.ca.sprintbbd.net ([24.221.190.179]:60557 "EHLO myware.akkadia.org") by vger.kernel.org with ESMTP id S265105AbUELPeN (ORCPT ); Wed, 12 May 2004 11:34:13 -0400 Message-ID: <40A243C8.401@redhat.com> Date: Wed, 12 May 2004 08:33:28 -0700 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8a) Gecko/20040511 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Eric W. Biederman" CC: "Randy.Dunlap" , fastboot@lists.osdl.org, lkml Subject: Re: [Fastboot] Re: [announce] kexec for linux 2.6.6 References: <20040511212625.28ac33ef.rddunlap@osdl.org> <40A1AF53.3010407@redhat.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Eric W. Biederman wrote: >> sym = dlsym (RTLD_DEFAULT, "the_symbol_name") > [...] > > For the momen the only finished port is x86, so we should be able > to do that, it would make the kernel patch a little bigger though. > Last time I saw that conversation I thought you didn't like symbols in > the vdso for syscalls because it slowed things down. I don't want to use this in glibc for every syscall. But for your random application in need of a syscall it's fine. And there is one more thing: the above code is actually not what should be used. The symbol able entries should be position independent. So one will have to compute the final address (which will be fun for archs with function descriptors). I'll have to see how randomization is actually implemented. The __kernel_vsyscall symbol is probably not changed, so we need an out-of-band mechanisms to report the load address to the userlevel code. -- ➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖