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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A9D3C433EF for ; Thu, 11 Nov 2021 01:23:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60C8161502 for ; Thu, 11 Nov 2021 01:23:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232782AbhKKB0F (ORCPT ); Wed, 10 Nov 2021 20:26:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:46836 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232733AbhKKB0E (ORCPT ); Wed, 10 Nov 2021 20:26:04 -0500 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 1295A61452; Thu, 11 Nov 2021 01:23:16 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.95) (envelope-from ) id 1mkyo6-000Afj-Tt; Wed, 10 Nov 2021 20:23:14 -0500 Message-ID: <20211111012314.755595288@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 10 Nov 2021 20:22:56 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Jiri Olsa Subject: [for-linus][PATCH 2/2] ftrace/direct: Fix lockup in modify_ftrace_direct_multi References: <20211111012254.044048524@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Olsa We can't call unregister_ftrace_function under ftrace_lock. Link: https://lkml.kernel.org/r/20211109114217.1645296-1-jolsa@kernel.org Fixes: ed29271894aa ("ftrace/direct: Do not disable when switching direct callers") Signed-off-by: Jiri Olsa Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b4ed1a301232..fc49e8809a56 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5602,10 +5602,11 @@ int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr) } } + mutex_unlock(&ftrace_lock); + /* Removing the tmp_ops will add the updated direct callers to the functions */ unregister_ftrace_function(&tmp_ops); - mutex_unlock(&ftrace_lock); out_direct: mutex_unlock(&direct_mutex); return err; -- 2.33.0