From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48998 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753668AbcKULk6 (ORCPT ); Mon, 21 Nov 2016 06:40:58 -0500 Subject: Patch "ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records" has been added to the 4.8-stable tree To: ast@fb.com, ast@kernel.org, gregkh@linuxfoundation.org, rostedt@goodmis.org Cc: , From: Date: Mon, 21 Nov 2016 12:40:59 +0100 Message-ID: <1479728459234196@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 ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records to the 4.8-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: ftrace-ignore-ftrace_fl_disabled-while-walking-dyn_ftrace-records.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 977c1f9c8c022d0173181766b34a0db3705265a4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 7 Nov 2016 15:14:20 -0800 Subject: ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records From: Alexei Starovoitov commit 977c1f9c8c022d0173181766b34a0db3705265a4 upstream. ftrace_shutdown() checks for sanity of ftrace records and if dyn_ftrace->flags is not zero, it will warn. It can happen that 'flags' are set to FTRACE_FL_DISABLED at this point, since some module was loaded, but before ftrace_module_enable() cleared the flags for this module. In other words the module.c is doing: ftrace_module_init(mod); // calls ftrace_update_code() that sets flags=FTRACE_FL_DISABLED ... // here ftrace_shutdown() is called that warns, since err = prepare_coming_module(mod); // didn't have a chance to clear FTRACE_FL_DISABLED Fix it by ignoring disabled records. It's similar to what __ftrace_hash_rec_update() is already doing. Link: http://lkml.kernel.org/r/1478560460-3818619-1-git-send-email-ast@fb.com Fixes: b7ffffbb46f2 "ftrace: Add infrastructure for delayed enabling of module functions" Signed-off-by: Alexei Starovoitov Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman --- kernel/trace/ftrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2757,7 +2757,7 @@ static int ftrace_shutdown(struct ftrace struct dyn_ftrace *rec; do_for_each_ftrace_rec(pg, rec) { - if (FTRACE_WARN_ON_ONCE(rec->flags)) + if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) pr_warn(" %pS flags:%lx\n", (void *)rec->ip, rec->flags); } while_for_each_ftrace_rec(); Patches currently in stable-queue which might be from ast@fb.com are queue-4.8/ftrace-ignore-ftrace_fl_disabled-while-walking-dyn_ftrace-records.patch