From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934399AbcECB3m (ORCPT ); Mon, 2 May 2016 21:29:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60604 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932399AbcECAd5 (ORCPT ); Mon, 2 May 2016 20:33:57 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adrian Hunter , David Ahern , Jiri Olsa , Namhyung Kim , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 4.4 135/163] perf evlist: Reference count the cpu and thread maps at set_maps() Date: Mon, 2 May 2016 17:12:43 -0700 Message-Id: <20160503000512.925210453@linuxfoundation.org> X-Mailer: git-send-email 2.8.2 In-Reply-To: <20160503000508.556845508@linuxfoundation.org> References: <20160503000508.556845508@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnaldo Carvalho de Melo commit a55e5663761366fb883f6f25375dd68bc958b9db upstream. We were dropping the reference we possibly held but not obtaining one for the new maps, which we will drop at perf_evlist__delete(), fix it. This was caught by Steven Noonan in some of the machines which would produce this output when caught by glibc debug mechanisms: $ sudo perf test 21 21: Test object code reading :*** Error in `perf': corrupted double-linked list: 0x00000000023ffcd0 *** ======= Backtrace: ========= /usr/lib/libc.so.6(+0x72055)[0x7f25be0f3055] /usr/lib/libc.so.6(+0x779b6)[0x7f25be0f89b6] /usr/lib/libc.so.6(+0x7a0ed)[0x7f25be0fb0ed] /usr/lib/libc.so.6(__libc_calloc+0xba)[0x7f25be0fceda] perf(parse_events_lex_init_extra+0x38)[0x4cfff8] perf(parse_events+0x55)[0x4a0615] perf(perf_evlist__config+0xcf)[0x4eeb2f] perf[0x479f82] perf(test__code_reading+0x1e)[0x47ad4e] perf(cmd_test+0x5dd)[0x46452d] perf[0x47f4e3] perf(main+0x603)[0x42c723] /usr/lib/libc.so.6(__libc_start_main+0xf0)[0x7f25be0a1610] perf(_start+0x29)[0x42c859] Further investigation using valgrind led to the reference count imbalance fixed in this patch. Reported-and-Tested-by: Steven Noonan Report-Link: http://lkml.kernel.org/r/CAKbGBLjC2Dx5vshxyGmQkcD+VwiAQLbHoXA9i7kvRB2-2opHZQ@mail.gmail.com Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Fixes: f30a79b012e5 ("perf tools: Add reference counting for cpu_map object") Link: http://lkml.kernel.org/n/tip-j0u1bdhr47sa511sgg76kb8h@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/evlist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1211,12 +1211,12 @@ void perf_evlist__set_maps(struct perf_e */ if (cpus != evlist->cpus) { cpu_map__put(evlist->cpus); - evlist->cpus = cpus; + evlist->cpus = cpu_map__get(cpus); } if (threads != evlist->threads) { thread_map__put(evlist->threads); - evlist->threads = threads; + evlist->threads = thread_map__get(threads); } perf_evlist__propagate_maps(evlist);