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=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 0509BC282E1 for ; Mon, 22 Apr 2019 09:36:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6067206A3 for ; Mon, 22 Apr 2019 09:36:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726953AbfDVJge (ORCPT ); Mon, 22 Apr 2019 05:36:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44896 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726164AbfDVJge (ORCPT ); Mon, 22 Apr 2019 05:36:34 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DB5B4C00735C; Mon, 22 Apr 2019 09:36:33 +0000 (UTC) Received: from krava (ovpn-204-20.brq.redhat.com [10.40.204.20]) by smtp.corp.redhat.com (Postfix) with SMTP id B7C3160139; Mon, 22 Apr 2019 09:36:30 +0000 (UTC) Date: Mon, 22 Apr 2019 11:36:29 +0200 From: Jiri Olsa To: Bo YU Cc: peterz@infradead.org, acme@kernel.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: <20190422093629.GA1730@krava> References: <20190422080138.10088-1-tsu.yubo@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190422080138.10088-1-tsu.yubo@gmail.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Mon, 22 Apr 2019 09:36:34 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 Acked-by: Jiri Olsa 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 >