From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752050AbeEKXaI (ORCPT ); Fri, 11 May 2018 19:30:08 -0400 Received: from mail-pl0-f49.google.com ([209.85.160.49]:34930 "EHLO mail-pl0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752017AbeEKXaA (ORCPT ); Fri, 11 May 2018 19:30:00 -0400 X-Google-Smtp-Source: AB8JxZrS5iCadfQfLcDoMCEQz77auP/YXPGV2Z4hFmE6nC9EyU93yKhZOr5O4rnS58DntsusMsnWFQ== Date: Sat, 12 May 2018 07:29:53 +0800 From: Leo Yan To: Arnaldo Carvalho de Melo Cc: Mathieu Poirier , Peter Zijlstra , Ingo Molnar , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND v2 1/2] perf cs-etm: Support unknown_thread in cs_etm_auxtrace Message-ID: <20180511232953.GA28378@leoy-ThinkPad-X240s> References: <1525924920-4381-1-git-send-email-leo.yan@linaro.org> <20180511134800.GO13491@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180511134800.GO13491@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 11, 2018 at 10:48:00AM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, May 10, 2018 at 12:01:59PM +0800, Leo Yan escreveu: > > CoreSight doesn't allocate thread structure for unknown_thread in etm > > auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't > > contain valid tid and then cs_etm__mem_access() uses unknown_thread > > instead as thread handler, this results in segmentation fault when > > thread__find_addr_map() accesses thread handler. > > > > This commit creates new thread data which is used by unknown_thread, so > > CoreSight tracing can roll back to use unknown_thread if perf data > > doesn't include valid thread info. This commit also releases thread > > data for initialization failure case and for normal auxtrace free flow. > > > > Signed-off-by: Leo Yan > > Acked-by: Mathieu Poirier > > Thanks, applied to perf/urgent. > > And please use a more descriptive, eye catching summary, something like: > > perf cs-etm: Fix segfault when accessing NULL unknown_thread variable > > :-) Thanks for suggestion. Indeed, this patch is a fix rather than a new feature, subject should reflect it. Thanks, Leo Yan From mboxrd@z Thu Jan 1 00:00:00 1970 From: leo.yan@linaro.org (Leo Yan) Date: Sat, 12 May 2018 07:29:53 +0800 Subject: [PATCH RESEND v2 1/2] perf cs-etm: Support unknown_thread in cs_etm_auxtrace In-Reply-To: <20180511134800.GO13491@kernel.org> References: <1525924920-4381-1-git-send-email-leo.yan@linaro.org> <20180511134800.GO13491@kernel.org> Message-ID: <20180511232953.GA28378@leoy-ThinkPad-X240s> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, May 11, 2018 at 10:48:00AM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, May 10, 2018 at 12:01:59PM +0800, Leo Yan escreveu: > > CoreSight doesn't allocate thread structure for unknown_thread in etm > > auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't > > contain valid tid and then cs_etm__mem_access() uses unknown_thread > > instead as thread handler, this results in segmentation fault when > > thread__find_addr_map() accesses thread handler. > > > > This commit creates new thread data which is used by unknown_thread, so > > CoreSight tracing can roll back to use unknown_thread if perf data > > doesn't include valid thread info. This commit also releases thread > > data for initialization failure case and for normal auxtrace free flow. > > > > Signed-off-by: Leo Yan > > Acked-by: Mathieu Poirier > > Thanks, applied to perf/urgent. > > And please use a more descriptive, eye catching summary, something like: > > perf cs-etm: Fix segfault when accessing NULL unknown_thread variable > > :-) Thanks for suggestion. Indeed, this patch is a fix rather than a new feature, subject should reflect it. Thanks, Leo Yan