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=-8.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 09F89C282CE for ; Mon, 22 Apr 2019 14:29:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD2E920685 for ; Mon, 22 Apr 2019 14:29:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="n7YFSKSw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727694AbfDVO3c (ORCPT ); Mon, 22 Apr 2019 10:29:32 -0400 Received: from mail-qt1-f194.google.com ([209.85.160.194]:44241 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726098AbfDVO3c (ORCPT ); Mon, 22 Apr 2019 10:29:32 -0400 Received: by mail-qt1-f194.google.com with SMTP id s10so1482578qtc.11; Mon, 22 Apr 2019 07:29:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=X+3KwgFLNI1DxbNWdLk+UeWpsRkqDazKZnichH+L7dk=; b=n7YFSKSw3t+otWf+aVLBd5dsR+PjeiJkEzpbZH9iIMHTb24NfeO6ImkJpTYt/bpV/4 o/DY21Sqw47Hib8fJ1iMrm3UzB2xzqvhqiOXxu98BGbrKX9fUxkHG9TXTpbhLiXugotN hqNaxJsX7UkMbkRT3+qAyizmA+AKpgcXmVBt8OUPW3IleUQoYr7KFssGP0+36XRDMzC9 oe7nBIGpxbx2R7BHiutx38R4mk6UqPw/93cT8wGTR1piz1unDVuPrruv/zdC4wC64rxx j9znbkqXXpcPrcUlFmiTAIUeBeaYEYnElqaInJyCdw2acHzRQZckhmmiRsdYrVCTJZyk khTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=X+3KwgFLNI1DxbNWdLk+UeWpsRkqDazKZnichH+L7dk=; b=YiytO9lbcAN87CiO33l2XJXNCz5EJIFiicV/NSfjVj7uMYwiECJ1wOfiUUQ7nTxJRx 2R5VIr1sbQYLUZnzivo2ud3vRz+rKfd9EhNzP0+M+Z+T27/gVa/aIl4T9oIMq8Z5HXdB 25oRB7xRR1pUf6Q2jd2E5IRc2b60cbrPIjqceqhB0wDxXrBkULPrsOEhrhPY1IjG0PdI onvwPCR49BzeKXLOU7Fexh6PjkJch5lEspWt5j/u3jVnAJ0DV4EZ/d0hgijG/OBWhUbk Yf5t+/Tf9Wb+sp7nK53DXTAgLjKnAFYfm8/nMa+g5LkJoZNe/8nAZRiPwYDx1yHXbxcS ri6A== X-Gm-Message-State: APjAAAW7xRT7cDuUEZ3d+dw6wFftBgwFk6Z8hCnmbzgKI8UDkRiNeeZT gFjvAmtSaEpL4gSDLACWQXk= X-Google-Smtp-Source: APXvYqzVFsdDHBaP6Z/GYiaEeq/kC11nlV2bsubD7yco9uy5v3i+8fdPGSiGbb2xBKCYuxzwcvGjrw== X-Received: by 2002:a0c:b885:: with SMTP id y5mr15693908qvf.25.1555943370529; Mon, 22 Apr 2019 07:29:30 -0700 (PDT) Received: from quaco.ghostprotocols.net ([190.15.121.82]) by smtp.gmail.com with ESMTPSA id s50sm8201865qts.39.2019.04.22.07.29.28 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 22 Apr 2019 07:29:29 -0700 (PDT) From: Arnaldo Carvalho de Melo X-Google-Original-From: Arnaldo Carvalho de Melo Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 7926F403EB; Mon, 22 Apr 2019 11:29:26 -0300 (-03) Date: Mon, 22 Apr 2019 11:29:26 -0300 To: Jiri Olsa Cc: Bo YU , peterz@infradead.org, alexander.shishkin@linux.intel.com, namhyung@kernel.org, ast@kernel.org, daniel@iogearbox.net, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, adrian.hunter@intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH] perf bpf: return value with unlocking in perf_env__find_btf() Message-ID: <20190422142926.GA11750@kernel.org> References: <20190422080138.10088-1-tsu.yubo@gmail.com> <20190422093629.GA1730@krava> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190422093629.GA1730@krava> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.11.3 (2019-02-01) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Em Mon, Apr 22, 2019 at 11:36:29AM +0200, Jiri Olsa escreveu: > On Mon, Apr 22, 2019 at 04:01:38AM -0400, Bo YU wrote: > > In perf_env__find_btf(), returning without unlocking > > "env->bpf_progs.lock". There may be cause lockdep issue. > > > > DEtected by CoversityScan, CID# 1444762:(program hangs(LOCK)) > > > > Fixes: 2db7b1e0bd49d: (perf bpf: Return NULL when RB tree lookup fails in perf_env__find_btf()) > > ugh, sry about that Brown paper bag on the part of everybody involved indeed :-\ > Acked-by: Jiri Olsa Applied. Thanks, - Arnaldo > thanks, > jirka > > > Signed-off-by: Bo YU > > --- > > tools/perf/util/env.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c > > index 9494f9dc61ec..6a3eaf7d9353 100644 > > --- a/tools/perf/util/env.c > > +++ b/tools/perf/util/env.c > > @@ -115,8 +115,8 @@ struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id) > > } > > node = NULL; > > > > - up_read(&env->bpf_progs.lock); > > out: > > + up_read(&env->bpf_progs.lock); > > return node; > > } > > > > -- > > 2.11.0 > > -- - Arnaldo