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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 BED57C38A2A for ; Thu, 7 May 2020 17:39:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DFF724958 for ; Thu, 7 May 2020 17:39:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728003AbgEGRjd (ORCPT ); Thu, 7 May 2020 13:39:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:35688 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726778AbgEGRja (ORCPT ); Thu, 7 May 2020 13:39:30 -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 D7B2D24955; Thu, 7 May 2020 17:39:29 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.93) (envelope-from ) id 1jWkUa-000Dmg-Pc; Thu, 07 May 2020 13:39:28 -0400 Message-ID: <20200507173928.673562862@goodmis.org> User-Agent: quilt/0.66 Date: Thu, 07 May 2020 13:39:07 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , stable@vger.kernel.org, Tom Zanussi , Masami Hiramatsu Subject: [for-linus][PATCH 3/9] tracing/boottime: Fix kprobe event API usage References: <20200507173904.729935165@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 boottime kprobe events to use API correctly for multiple events. For example, when we set a multiprobe kprobe events in bootconfig like below, ftrace.event.kprobes.myevent { probes = "vfs_read $arg1 $arg2", "vfs_write $arg1 $arg2" } This cause an error; trace_boot: Failed to add probe: p:kprobes/myevent (null) vfs_read $arg1 $arg2 vfs_write $arg1 $arg2 This shows the 1st argument becomes NULL and multiprobes are merged to 1 probe. Link: http://lkml.kernel.org/r/158779375766.6082.201939936008972838.stgit@devnote2 Cc: Ingo Molnar Cc: stable@vger.kernel.org Fixes: 29a154810546 ("tracing: Change trace_boot to use kprobe_event interface") Reviewed-by: Tom Zanussi Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_boot.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 06d7feb5255f..9de29bb45a27 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -95,24 +95,20 @@ trace_boot_add_kprobe_event(struct xbc_node *node, const char *event) struct xbc_node *anode; char buf[MAX_BUF_LEN]; const char *val; - int ret; + int ret = 0; - kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN); + xbc_node_for_each_array_value(node, "probes", anode, val) { + kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN); - ret = kprobe_event_gen_cmd_start(&cmd, event, NULL); - if (ret) - return ret; + ret = kprobe_event_gen_cmd_start(&cmd, event, val); + if (ret) + break; - xbc_node_for_each_array_value(node, "probes", anode, val) { - ret = kprobe_event_add_field(&cmd, val); + ret = kprobe_event_gen_cmd_end(&cmd); if (ret) - return ret; + pr_err("Failed to add probe: %s\n", buf); } - ret = kprobe_event_gen_cmd_end(&cmd); - if (ret) - pr_err("Failed to add probe: %s\n", buf); - return ret; } #else -- 2.26.2