Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753819AbbDAOsp (ORCPT ); Wed, 1 Apr 2015 10:48:45 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:34688 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753388AbbDAOso (ORCPT ); Wed, 1 Apr 2015 10:48:44 -0400 Date: Wed, 1 Apr 2015 16:48:39 +0200 From: Ingo Molnar To: Wang Nan Cc: acme@kernel.org, jolsa@kernel.org, namhyung@kernel.org, mingo@redhat.com, lizefan@huawei.com, pi3orama@163.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] perf: unwind: fix segbase for libunwind. Message-ID: <20150401144839.GA17340@gmail.com> References: <1427897332-145581-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1427897332-145581-1-git-send-email-wangnan0@huawei.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 828 Lines: 25 * Wang Nan wrote: > Perf passes incorrect segbase and table_data to libunwind when > map->pgoff != 0, causes unwind failure. This patch fixes this > problem. > > segbase is an absolute offset from the head of object file, directly > read from ELF file. Original code computes corresponding virtual > address using map->start + segbase, doesn't consider map->pgoff. > Which causes libunwind read from incorrect offset. What's the effect of this bug in practice? Is there any before/after output you can show that demonstrates the fix? Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/