From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43286 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751283AbbEBRTS (ORCPT ); Sat, 2 May 2015 13:19:18 -0400 Subject: Patch "tracing: Fix incorrect enabling of trace events by boot cmdline" has been added to the 4.0-stable tree To: iamjoonsoo.kim@lge.com, gregkh@linuxfoundation.org, rostedt@goodmis.org Cc: , From: Date: Sat, 02 May 2015 19:18:03 +0200 Message-ID: <1430587083126247@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled tracing: Fix incorrect enabling of trace events by boot cmdline to the 4.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tracing-fix-incorrect-enabling-of-trace-events-by-boot-cmdline.patch and it can be found in the queue-4.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 84fce9db4d7eaebd6cb2ee30c15da6d4e4daf846 Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Thu, 16 Apr 2015 13:44:44 +0900 Subject: tracing: Fix incorrect enabling of trace events by boot cmdline From: Joonsoo Kim commit 84fce9db4d7eaebd6cb2ee30c15da6d4e4daf846 upstream. There is a problem that trace events are not properly enabled with boot cmdline. The problem is that if we pass "trace_event=kmem:mm_page_alloc" to the boot cmdline, it enables all kmem trace events, and not just the page_alloc event. This is caused by the parsing mechanism. When we parse the cmdline, the buffer contents is modified due to tokenization. And, if we use this buffer again, we will get the wrong result. Unfortunately, this buffer is be accessed three times to set trace events properly at boot time. So, we need to handle this situation. There is already code handling ",", but we need another for ":". This patch adds it. Link: http://lkml.kernel.org/r/1429159484-22977-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim [ added missing return ret; ] Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_events.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -565,6 +565,7 @@ static int __ftrace_set_clr_event(struct static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set) { char *event = NULL, *sub = NULL, *match; + int ret; /* * The buf format can be : @@ -590,7 +591,13 @@ static int ftrace_set_clr_event(struct t event = NULL; } - return __ftrace_set_clr_event(tr, match, sub, event, set); + ret = __ftrace_set_clr_event(tr, match, sub, event, set); + + /* Put back the colon to allow this to be called again */ + if (buf) + *(buf - 1) = ':'; + + return ret; } /** Patches currently in stable-queue which might be from iamjoonsoo.kim@lge.com are queue-4.0/tracing-fix-incorrect-enabling-of-trace-events-by-boot-cmdline.patch