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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 93E6AC7112B for ; Sun, 14 Oct 2018 15:32:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 665BA20835 for ; Sun, 14 Oct 2018 15:32:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 665BA20835 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728652AbeJNXNt (ORCPT ); Sun, 14 Oct 2018 19:13:49 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36337 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728202AbeJNXMF (ORCPT ); Sun, 14 Oct 2018 19:12:05 -0400 Received: from [2a02:8011:400e:2:cbab:f00:c93f:614] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1gBiLs-0004cI-N2; Sun, 14 Oct 2018 16:30:44 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gBiLW-0000Ub-JD; Sun, 14 Oct 2018 16:30:22 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, syzbot+9c0d616860575a73166a@syzkaller.appspotmail.com, "Steven Rostedt (VMware)" , syzbot+4e9ae7fa46233396f64d@syzkaller.appspotmail.com, "Arnaldo Carvalho de Melo" , "Jiri Olsa" , "Peter Zijlstra" , "Alexander Shishkin" , "Mathieu Desnoyers" , "Namhyung Kim" Date: Sun, 14 Oct 2018 16:25:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 245/366] tracepoint: Do not warn on ENOMEM In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:cbab:f00:c93f:614 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mathieu Desnoyers commit d66a270be3310d7aa132fec0cea77d3d32a0ff75 upstream. Tracepoint should only warn when a kernel API user does not respect the required preconditions (e.g. same tracepoint enabled twice, or called to remove a tracepoint that does not exist). Silence warning in out-of-memory conditions, given that the error is returned to the caller. This ensures that out-of-memory error-injection testing does not trigger warnings in tracepoint.c, which were seen by syzbot. Link: https://lkml.kernel.org/r/001a114465e241a8720567419a72@google.com Link: https://lkml.kernel.org/r/001a1140e0de15fc910567464190@google.com Link: http://lkml.kernel.org/r/20180315124424.32319-1-mathieu.desnoyers@efficios.com CC: Peter Zijlstra CC: Jiri Olsa CC: Arnaldo Carvalho de Melo CC: Alexander Shishkin CC: Namhyung Kim Fixes: de7b2973903c6 ("tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints") Reported-by: syzbot+9c0d616860575a73166a@syzkaller.appspotmail.com Reported-by: syzbot+4e9ae7fa46233396f64d@syzkaller.appspotmail.com Signed-off-by: Mathieu Desnoyers Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Ben Hutchings --- kernel/tracepoint.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -185,7 +185,7 @@ static int tracepoint_add_func(struct tr lockdep_is_held(&tracepoints_mutex)); old = func_add(&tp_funcs, func); if (IS_ERR(old)) { - WARN_ON_ONCE(1); + WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); return PTR_ERR(old); } @@ -218,7 +218,7 @@ static int tracepoint_remove_func(struct lockdep_is_held(&tracepoints_mutex)); old = func_remove(&tp_funcs, func); if (IS_ERR(old)) { - WARN_ON_ONCE(1); + WARN_ON_ONCE(PTR_ERR(old) != -ENOMEM); return PTR_ERR(old); }