From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from thoth.sbs.de ([192.35.17.2]:46843 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727429AbfJQOMb (ORCPT ); Thu, 17 Oct 2019 10:12:31 -0400 Subject: Re: [PATCH v2] scripts/gdb: fix debugging modules on s390 From: Jan Kiszka References: <20191017085917.81791-1-iii@linux.ibm.com> Message-ID: Date: Thu, 17 Oct 2019 16:12:18 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Ilya Leoshkevich , Kieran Bingham , linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Andrew Morton Cc: Heiko Carstens , Vasily Gorbik On 17.10.19 16:11, Jan Kiszka wrote: > On 17.10.19 10:59, Ilya Leoshkevich wrote: >> Currently lx-symbols assumes that module text is always located at >> module->core_layout->base, but s390 uses the following layout: >> >> +------+ <- module->core_layout->base >> | GOT | >> +------+ <- module->core_layout->base + module->arch->plt_offset >> | PLT | >> +------+ <- module->core_layout->base + module->arch->plt_offset + >> | TEXT | module->arch->plt_size >> +------+ >> >> Therefore, when trying to debug modules on s390, all the symbol >> addresses are skewed by plt_offset + plt_size. >> >> Fix by adding plt_offset + plt_size to module_addr in >> load_module_symbols(). >> >> Signed-off-by: Ilya Leoshkevich >> --- >> >> v1 -> v2: print the adjusted address. >> >> scripts/gdb/linux/symbols.py | 8 +++++++- >> 1 file changed, 7 insertions(+), 1 deletion(-) >> >> diff --git a/scripts/gdb/linux/symbols.py b/scripts/gdb/linux/symbols.py >> index f0d8f2ecfde7..df4c810de663 100644 >> --- a/scripts/gdb/linux/symbols.py >> +++ b/scripts/gdb/linux/symbols.py >> @@ -15,7 +15,7 @@ import gdb >> import os >> import re >> >> -from linux import modules >> +from linux import modules, utils >> >> >> if hasattr(gdb, 'Breakpoint'): >> @@ -111,6 +111,12 @@ lx-symbols command.""" >> module_file = self._get_module_file(module_name) >> >> if module_file: >> + if utils.is_target_arch('s390'): >> + # Module text is preceded by PLT stubs on s390. >> + module_arch = module['arch'] >> + plt_offset = int(module_arch['plt_offset']) >> + plt_size = int(module_arch['plt_size']) >> + module_addr = hex(int(module_addr, 0) + plt_offset + plt_size) >> gdb.write("loading @{addr}: {filename}\n".format( >> addr=module_addr, filename=module_file)) >> cmdline = "add-symbol-file {filename} {addr}{sections}".format( >> > > Reviewed-by: Jan Kiszka > > Thanks, > Jan > Sorry, forgot to CC Andrew for pickup. Jan -- Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux