From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759385AbZCRR6Z (ORCPT ); Wed, 18 Mar 2009 13:58:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757446AbZCRR6K (ORCPT ); Wed, 18 Mar 2009 13:58:10 -0400 Received: from hera.kernel.org ([140.211.167.34]:47232 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756258AbZCRR6J (ORCPT ); Wed, 18 Mar 2009 13:58:09 -0400 Date: Wed, 18 Mar 2009 17:57:27 GMT From: Jaswinder Singh Rajput To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, jaswinder@kernel.org, jaswinderrajput@gmail.com, fweisbec@gmail.com, rostedt@goodmis.org, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, jaswinder@kernel.org, jaswinderrajput@gmail.com, fweisbec@gmail.com, rostedt@goodmis.org, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <1237394936.3132.1.camel@localhost.localdomain> References: <1237394936.3132.1.camel@localhost.localdomain> Subject: [tip:tracing/ftrace] tracing: fix oops in tracepoint_update_probe_range() Message-ID: Git-Commit-ID: 09933a108e6730a464a1ab676c9decc11aee0edc X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Wed, 18 Mar 2009 17:57:29 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 09933a108e6730a464a1ab676c9decc11aee0edc Gitweb: http://git.kernel.org/tip/09933a108e6730a464a1ab676c9decc11aee0edc Author: Jaswinder Singh Rajput AuthorDate: Wed, 18 Mar 2009 22:18:56 +0530 Commit: Ingo Molnar CommitDate: Wed, 18 Mar 2009 18:54:39 +0100 tracing: fix oops in tracepoint_update_probe_range() Change this crash: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] tracepoint_update_probe_range+0x1f/0x9b PGD 13d5fb067 PUD 13d688067 PMD 0 Oops: 0000 [#1] SMP To a more debuggable WARN_ONCE(). Signed-off-by: Jaswinder Singh Rajput Cc: Frederic Weisbecker Cc: Steven Rostedt LKML-Reference: <1237394936.3132.1.camel@localhost.localdomain> [ moved the check outside the lock and added a WARN_ON(). ] Signed-off-by: Ingo Molnar --- kernel/tracepoint.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 7960274..adf2873 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -272,12 +272,17 @@ static void disable_tracepoint(struct tracepoint *elem) * * Updates the probe callback corresponding to a range of tracepoints. */ -void tracepoint_update_probe_range(struct tracepoint *begin, - struct tracepoint *end) +void +tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end) { struct tracepoint *iter; struct tracepoint_entry *mark_entry; + if (!begin) { + WARN_ON_ONCE(1); + return; + } + mutex_lock(&tracepoints_mutex); for (iter = begin; iter < end; iter++) { mark_entry = get_tracepoint(iter->name);