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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 D38FFC4CEC4 for ; Wed, 18 Sep 2019 08:55:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A9A5921907 for ; Wed, 18 Sep 2019 08:55:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568796942; bh=+lueAAsQKUqeGKnYxOeGimMVjVTFw3fNJB+UmXbLp+w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PA6iaEdONG7LuTGN31tQENxM8DHgBdVwl+u4IwdgbsgQzOgei/YYniz/D0ja8SQiU tSQyfR5TH3fJ728Y+GgORF7HzdRs7HmSrC0LLaq6KHE8a9YOH/Tq4hm+h9n66KhuUn 5IXKnZefVRIoxnlv73gvGYJs0WI6scIkvf/x9NHA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730646AbfIRIzl (ORCPT ); Wed, 18 Sep 2019 04:55:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:44054 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726668AbfIRIzl (ORCPT ); Wed, 18 Sep 2019 04:55:41 -0400 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C21DC218AF; Wed, 18 Sep 2019 08:55:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568796940; bh=+lueAAsQKUqeGKnYxOeGimMVjVTFw3fNJB+UmXbLp+w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yFOqMA0SiekAE3k6wEzp+G/fz1wZ7RSSmko1VoBA+4gkoy3zbhm0Fs4O2/wm2wD26 DYiMk0K0VH2f81z7fzHv25uxXC3VQGQwYW3Z8jbh3IsmWOzeBxlGFY4fZu6sSvJWlp shzB006ItQ6ixXJx2nl6oAhc7KNVTpwgbFI3FAxw= From: Masami Hiramatsu To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, mhiramat@kernel.org, mingo@redhat.com Subject: [PATCH 1/3] tracing/probe: Fix to allow user to enable events on unloaded modules Date: Wed, 18 Sep 2019 17:55:37 +0900 Message-Id: <156879693733.31056.9331322616994665167.stgit@devnote2> X-Mailer: git-send-email 2.20.1 In-Reply-To: <156879692790.31056.9404391078827158266.stgit@devnote2> References: <156879692790.31056.9404391078827158266.stgit@devnote2> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Masami Hiramatsu --- 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;