From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3372 invoked by alias); 24 Jun 2013 13:47:16 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 3359 invoked by uid 89); 24 Jun 2013 13:47:16 -0000 X-Spam-SWARE-Status: No, score=-4.7 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_HOSTKARMA_W,RCVD_IN_HOSTKARMA_WL autolearn=ham version=3.3.1 Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Mon, 24 Jun 2013 13:47:09 +0000 Received: from svr-orw-exc-10.mgc.mentorg.com ([147.34.98.58]) by relay1.mentorg.com with esmtp id 1Ur76q-00075x-E3 from Luis_Gustavo@mentor.com ; Mon, 24 Jun 2013 06:47:08 -0700 Received: from NA1-MAIL.mgc.mentorg.com ([147.34.98.181]) by SVR-ORW-EXC-10.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.4675); Mon, 24 Jun 2013 06:47:08 -0700 Received: from [172.30.15.64] ([172.30.15.64]) by NA1-MAIL.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.3959); Mon, 24 Jun 2013 06:47:07 -0700 Message-ID: <51C84DD4.4090001@codesourcery.com> Date: Mon, 24 Jun 2013 14:25:00 -0000 From: Luis Machado Reply-To: lgustavo@codesourcery.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Yao Qi CC: "'gdb-patches@sourceware.org'" , Mike Frysinger Subject: Re: [PATCH, gdbserver] Further cleanup of FDPIC/DSBT divergences References: <51C34F14.8070803@codesourcery.com> <51C84CBD.10506@codesourcery.com> In-Reply-To: <51C84CBD.10506@codesourcery.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2013-06/txt/msg00651.txt.bz2 On 06/24/2013 10:42 AM, Yao Qi wrote: > On 06/21/2013 02:51 AM, Luis Machado wrote: >> Things have changed, and c6x is now using the exact same data structures >> as FDPIC-based targets in uClibc. Please refer to >> http://lists.uclibc.org/pipermail/uclibc/2013-May/047789.html for the >> uClibc changes that led to this. >> >> Mark Salter, the author of the uClibc change, has agreed with the >> solution i proposed: >> http://lists.uclibc.org/pipermail/uclibc/2013-May/047790.html. >> >> It is all good, but we've been conditionalizing the c6x-specific >> target_loadmap data structure based on the presence of PT_GETDSBT. This >> has always been defined in uClibc and, since Mark's change, it doesn't >> work as a hint of whether to use the new or the old target_loadmap data >> structure anymore. Therefore we will/already have a potential problem >> with backwards compatibility. >> >> Bernhard has stated that backwards compatibility on uClibc's side is not >> a problem:http://lists.uclibc.org/pipermail/uclibc/2013-June/047801.html. >> >> With all that exposed, my proposed change to gdbserver is to drop all >> the DSBT-specific bits, remove their definitions and explicitly use >> FDPIC definitions instead, making things a little bit cleaner. >> >> In the following patch i also changed the code slightly to stop defining >> linux_read_loadmap to NULL and i switched to explicitly setting the >> target hook to NULL in the absence of the required definition. >> >> What do you think? Yao? Mike? > > Luis, > Looks Mark S. proposed using FDPIC in tic6x port in kernel, instead of > DSBT which was used when we did the tic6x port in GDB. I checked the > kernel log, and found that DSBT constants are never used in the official > kernel. They only appeared in the linux-c6x.org git tree temporarily. > Since kernel and uclibc has migrated to the new scheme, I don't worry > about the compatibility issue here. > >> >> 2013-06-20 Luis Machado >> >> * linux-low.c: Remove check for PT_GETDSBT. >> (target_loadmap): Remove data structure conditionalized by >> the presence of PT_GETDSBT. >> (LINUX_LOADMAP, LINUX_LOADMAP_EXEC, >> LINUX_LOADMAP_INTERP): Remove definitions. > > Not sure we can break words in parentheses into multiple lines. I suggest: > > (LINUX_LOADMAP, LINUX_LOADMAP_EXEC): Remove definitions. > (LINUX_LOADMAP_INTERP): Likewise. > > the patch is OK to me, but we also need adjustments in solib-dsbt.c. > This patch should go in together with the changes in solib-dsbt.c. > Thanks Yao. You are correct. Let me address the solib-dsbt.c bits as well. Luis