From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753277AbZFBSqx (ORCPT ); Tue, 2 Jun 2009 14:46:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751856AbZFBSqE (ORCPT ); Tue, 2 Jun 2009 14:46:04 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:61801 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751300AbZFBSqA (ORCPT ); Tue, 2 Jun 2009 14:46:00 -0400 Message-Id: <20090602183036.621443366@goodmis.org> User-Agent: quilt/0.46-1 Date: Tue, 02 Jun 2009 14:30:36 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , stable@kernel.org, "Luis Claudio R. Goncalves" , Oleg Nesterov Subject: [PATCH 0/3] [GIT PULL][urgent] function-graph: memory leak and race fixes Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo, During testing of the -rt patch, Luis found a bug with the function profiler (not in 30-rc and I sent the patch for you already), that he could trigger a crash when enabling and disabling the function profiler in a loop. During my investigation of this, I tried enabling and disabling the function graph tracer in a loop and was able to also crash the kernel. This crash was not the same as the profiler crash. Looking into this I found a few problems with the enabling of the function graph tracer. One was a memory leak, the other two were races on SMP machines. The races were more likely the cause of the crashes I saw. With these patches applied, I no longer can produce the crash. I've also Cc'd the stable team since these bugs also exist in 2.6.29. Please pull the latest tip/tracing/urgent tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git tip/tracing/urgent Steven Rostedt (3): function-graph: only allocate init tasks if it was not already done function-graph: enable the stack after initialization of other variables function-graph: add memory barriers for accessing task's ret_stack ---- kernel/trace/ftrace.c | 23 +++++++++++++++-------- kernel/trace/trace_functions_graph.c | 6 ++++++ 2 files changed, 21 insertions(+), 8 deletions(-) --