From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964872AbXBOCnr (ORCPT ); Wed, 14 Feb 2007 21:43:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964873AbXBOCnr (ORCPT ); Wed, 14 Feb 2007 21:43:47 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:48430 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964872AbXBOCnq (ORCPT ); Wed, 14 Feb 2007 21:43:46 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: Jeremy Fitzhardinge Cc: Andi Kleen , Andrew Morton , linux-kernel@vger.kernel.org, virtualization@lists.osdl.org, xen-devel@lists.xensource.com, Chris Wright , Zachary Amsden , Ian Campbell Subject: Re: [patch 16/21] Xen-paravirt: Add code into head.S to handle being booted by Xen References: <20070213221729.772002682@goop.org> <20070213221830.707197267@goop.org> <20070213235424.GA1908@muc.de> <45D35ABE.1050504@goop.org> <45D3740A.4080600@goop.org> <45D3A5A4.7080804@goop.org> <45D3BCC6.9020807@goop.org> <45D3C42C.1020005@goop.org> Date: Wed, 14 Feb 2007 19:41:37 -0700 In-Reply-To: <45D3C42C.1020005@goop.org> (Jeremy Fitzhardinge's message of "Wed, 14 Feb 2007 18:23:40 -0800") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge writes: > Eric W. Biederman wrote: >> I'm pretty certain we explicitly drop the weird GNU note that >> is automatically generated by gcc and specifies something informational. >> > But that's something else again, since it appears as a PT_GNU_STACK phdr. Not that. It's more like abi version or gcc version or something like. At least there used to be one of those notes in every .o file and compiled program. >> I don't think anything we are doing is wrong but ld gets confused easily >> in the corner cases. I'm modestly surprised we didn't have to mark our >> .note.xxx scions as ".section .note.xxx @note" or whatever the proper >> gas syntax is. > > I did try that, and it didn't make a difference. The manual says that > the output section type follows the input section type, so I agree its a > bit surprising we ever get a SHT_NOTE out of it without the @note stuff. Right. So the surprise is that SHT_NOTE got set. There are some defaults based on the section name somewhere that appear to have done the right thing. My best hunch really is that ld treated the .note sections normally and just mist the handling of the magic SHT_NOTE type. Which is why I'm not to worried. Eric From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [patch 16/21] Xen-paravirt: Add code into head.S to handle being booted by Xen Date: Wed, 14 Feb 2007 19:41:37 -0700 Message-ID: References: <20070213221729.772002682@goop.org> <20070213221830.707197267@goop.org> <20070213235424.GA1908@muc.de> <45D35ABE.1050504@goop.org> <45D3740A.4080600@goop.org> <45D3A5A4.7080804@goop.org> <45D3BCC6.9020807@goop.org> <45D3C42C.1020005@goop.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <45D3C42C.1020005@goop.org> (Jeremy Fitzhardinge's message of "Wed, 14 Feb 2007 18:23:40 -0800") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.osdl.org Errors-To: virtualization-bounces@lists.osdl.org To: Jeremy Fitzhardinge Cc: Andrew Morton , Andi Kleen , xen-devel@lists.xensource.com, Chris Wright , virtualization@lists.osdl.org, Ian Campbell , linux-kernel@vger.kernel.org List-Id: virtualization@lists.linuxfoundation.org Jeremy Fitzhardinge writes: > Eric W. Biederman wrote: >> I'm pretty certain we explicitly drop the weird GNU note that >> is automatically generated by gcc and specifies something informational. >> = > But that's something else again, since it appears as a PT_GNU_STACK phdr. Not that. It's more like abi version or gcc version or something like. At least there used to be one of those notes in every .o file and compiled program. >> I don't think anything we are doing is wrong but ld gets confused easily >> in the corner cases. I'm modestly surprised we didn't have to mark our >> .note.xxx scions as ".section .note.xxx @note" or whatever the proper >> gas syntax is. > > I did try that, and it didn't make a difference. The manual says that > the output section type follows the input section type, so I agree its a > bit surprising we ever get a SHT_NOTE out of it without the @note stuff. Right. So the surprise is that SHT_NOTE got set. There are some defaults based on the section name somewhere that appear to have done the right thing. My best hunch really is that ld treated the .note sections normally and just mist the handling of the magic SHT_NOTE type. Which is why I'm not to worried. Eric