From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B6DBC636C9 for ; Thu, 15 Jul 2021 19:24:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00752610F9 for ; Thu, 15 Jul 2021 19:24:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243224AbhGOT04 (ORCPT ); Thu, 15 Jul 2021 15:26:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:34418 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244114AbhGOTXV (ORCPT ); Thu, 15 Jul 2021 15:23:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7B364613EE; Thu, 15 Jul 2021 19:20:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626376827; bh=9A8L60acZh/ranYawGu7poVBjCxHO7CttpSh7b6fvAo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MLPz6UvPpVSeTEhG7DRMMhNw6AHfa9/UtedLxtdI765oz9xHp0Y7Vc6oIRnLMEH2p Fmq50zUt/KEYpcOiFfbORKuj2G6CFQi7y8gKVuudePvhFqM5ZCWL8mJt+74sT/XNQG JxmbvLetoXG3W6DE0uGSLlWHagOHbR3XL5yWROgsY1jDVXfimz6QKvgakDa0vdRYXH bKUfUZRs29q/qCkyNgkLDUUzzkoPAArzPz0DmCvSBAB1gmd0ru539NarR6k0e4ESfR UG/Y79sPimS9kV2Cr2PHYnG24inRtzJWi8coHmYY+7GVAjIoUfg+anVYr8oknDC8hZ YTU7GyIQxu/Ag== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id D1788403F2; Thu, 15 Jul 2021 16:20:24 -0300 (-03) Date: Thu, 15 Jul 2021 16:20:24 -0300 From: Arnaldo Carvalho de Melo To: Riccardo Mancini , Krister Johansen Cc: Ian Rogers , Namhyung Kim , Peter Zijlstra , Ingo Molnar , Mark Rutland , Jiri Olsa , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: Re: [PATCH 01/20] perf nsinfo: fix refcounting Message-ID: References: <55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Em Thu, Jul 15, 2021 at 04:02:16PM -0300, Arnaldo Carvalho de Melo escreveu: > Em Thu, Jul 15, 2021 at 06:07:06PM +0200, Riccardo Mancini escreveu: > > ASan reports a memory leak of nsinfo during the execution of the perf > > test "31: Lookup mmap thread". > > The leak is caused by a refcounted variable being replaced without > > dropping the refcount. > > This patch makes sure that the refcnt of nsinfo is decreased whenever > > a refcounted variable is replaced with a new value. > So, there are multiple fixes in just one patch, I'll split it into > three, no need to resend. > I'll try and check if finding Fixes: for the three is easy, that way > stable@vger.kernel.org will figure out which of the supported releases > need each of them. The second is at the end of this message, and looking at it I think there is a problem with where this nsinfo reference is stored, it should be in the 'struct map', that is per-thread, not in the 'struct dso', that may be shared by multiple 'struct map's in different cgroups, so we can't set dso->nsinfo in map__new(), right? Kristen? - Arnaldo commit 280f3933661f9ca9563ed04ce82313fdbcbb8f75 Author: Riccardo Mancini Date: Thu Jul 15 18:07:06 2021 +0200 perf map: Fix dso->nsinfo refcounting ASan reports a memory leak of nsinfo during the execution of # perf test "31: Lookup mmap thread" The leak is caused by a refcounted variable being replaced without dropping the refcount. This patch makes sure that the refcnt of nsinfo is decreased whenever a refcounted variable is replaced with a new value. Signed-off-by: Riccardo Mancini Fixes: bf2e710b3cb8445c ("perf maps: Lookup maps in both intitial mountns and inner mountns.") Cc: Ian Rogers Cc: Jiri Olsa Cc: Krister Johansen Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 8af693d9678cefe0..72e7f3616157ead4 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -192,6 +192,8 @@ struct map *map__new(struct machine *machine, u64 start, u64 len, if (!(prot & PROT_EXEC)) dso__set_loaded(dso); } + + nsinfo__put(dso->nsinfo); dso->nsinfo = nsi; if (build_id__is_defined(bid))