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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 EE668C4363D for ; Wed, 23 Sep 2020 22:56:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E2B023119 for ; Wed, 23 Sep 2020 22:56:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726620AbgIWW4Q convert rfc822-to-8bit (ORCPT ); Wed, 23 Sep 2020 18:56:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:50678 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726537AbgIWW4Q (ORCPT ); Wed, 23 Sep 2020 18:56:16 -0400 Received: from oasis.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 48908221EB; Wed, 23 Sep 2020 22:56:15 +0000 (UTC) Date: Wed, 23 Sep 2020 18:56:13 -0400 From: Steven Rostedt To: Cc: zhouchengming@bytedance.com, songmuchun@bytedance.com, Subject: Re: FAILED: patch "[PATCH] ftrace: Setup correct FTRACE_FL_REGS flags for module" failed to apply to 4.4-stable tree Message-ID: <20200923185613.6901e246@oasis.local.home> In-Reply-To: <159784015193138@kroah.com> References: <159784015193138@kroah.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, 19 Aug 2020 14:29:11 +0200 wrote: > The patch below does not apply to the 4.4-stable tree. > If someone wants it applied there, or to any other stable or longterm > tree, then please email the backport, including the original git commit > id to . This should be the fix for 4.4. -- Steve >From 8a224ffb3f52b0027f6b7279854c71a31c48fc97 Mon Sep 17 00:00:00 2001 From: Chengming Zhou Date: Wed, 29 Jul 2020 02:05:53 +0800 Subject: [PATCH] ftrace: Setup correct FTRACE_FL_REGS flags for module When module loaded and enabled, we will use __ftrace_replace_code for module if any ftrace_ops referenced it found. But we will get wrong ftrace_addr for module rec in ftrace_get_addr_new, because rec->flags has not been setup correctly. It can cause the callback function of a ftrace_ops has FTRACE_OPS_FL_SAVE_REGS to be called with pt_regs set to NULL. So setup correct FTRACE_FL_REGS flags for rec when we call referenced_filters to find ftrace_ops references it. Link: https://lkml.kernel.org/r/20200728180554.65203-1-zhouchengming@bytedance.com Cc: stable@vger.kernel.org Fixes: 8c4f3c3fa9681 ("ftrace: Check module functions being traced on reload") Signed-off-by: Chengming Zhou Signed-off-by: Muchun Song Signed-off-by: Steven Rostedt (VMware) Index: linux-test.git/kernel/trace/ftrace.c =================================================================== --- linux-test.git.orig/kernel/trace/ftrace.c +++ linux-test.git/kernel/trace/ftrace.c @@ -2823,8 +2823,11 @@ static int referenced_filters(struct dyn int cnt = 0; for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { - if (ops_references_rec(ops, rec)) - cnt++; + if (ops_references_rec(ops, rec)) { + cnt++; + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) + rec->flags |= FTRACE_FL_REGS; + } } return cnt; @@ -2874,7 +2877,7 @@ static int ftrace_update_code(struct mod p = &pg->records[i]; if (test) cnt += referenced_filters(p); - p->flags = cnt; + p->flags += cnt; /* * Do the initial record conversion from mcount jump