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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 AF6E8C3A5A6 for ; Thu, 19 Sep 2019 23:24:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 823A4214AF for ; Thu, 19 Sep 2019 23:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407158AbfISXY0 (ORCPT ); Thu, 19 Sep 2019 19:24:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:35684 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405687AbfISXYB (ORCPT ); Thu, 19 Sep 2019 19:24:01 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3624D21929; Thu, 19 Sep 2019 23:24:01 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.92) (envelope-from ) id 1iB5mK-0000hZ-DF; Thu, 19 Sep 2019 19:24:00 -0400 Message-Id: <20190919232400.299074257@goodmis.org> User-Agent: quilt/0.65 Date: Thu, 19 Sep 2019 19:23:19 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , stable@vger.kernel.org, Masami Hiramatsu Subject: [for-next][PATCH 6/8] tracing/probe: Fix to allow user to enable events on unloaded modules References: <20190919232313.198902049@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Fix to allow user to enable probe events on unloaded modules. This operations was allowed before commit 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe"), because if users need to probe module init functions, they have to enable those probe events before loading module. Link: http://lkml.kernel.org/r/156879693733.31056.9331322616994665167.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_kprobe.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 7579c53bb053..0ba3239c0270 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -371,31 +371,24 @@ static int enable_trace_kprobe(struct trace_event_call *call, if (enabled) return 0; - enabled = false; list_for_each_entry(pos, trace_probe_probe_list(tp), list) { tk = container_of(pos, struct trace_kprobe, tp); if (trace_kprobe_has_gone(tk)) continue; ret = __enable_trace_kprobe(tk); - if (ret) { - if (enabled) { - __disable_trace_kprobe(tp); - enabled = false; - } + if (ret) break; - } enabled = true; } - if (!enabled) { - /* No probe is enabled. Roll back */ + if (ret) { + /* Failed to enable one of them. Roll back all */ + if (enabled) + __disable_trace_kprobe(tp); if (file) trace_probe_remove_file(tp, file); else trace_probe_clear_flag(tp, TP_FLAG_PROFILE); - if (!ret) - /* Since all probes are gone, this is not available */ - ret = -EADDRNOTAVAIL; } return ret; -- 2.20.1