Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753316AbbFOA5x (ORCPT ); Sun, 14 Jun 2015 20:57:53 -0400 Received: from mga02.intel.com ([134.134.136.20]:15401 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752445AbbFOA5o (ORCPT ); Sun, 14 Jun 2015 20:57:44 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,615,1427785200"; d="scan'208";a="727292852" Date: Mon, 15 Jun 2015 08:57:04 +0800 From: Fengguang Wu To: Frederic Weisbecker Cc: Ingo Molnar , "Peter Zijlstra (Intel)" , LKP , LKML Subject: Re: [sched/preempt] BUG: KASan: out of bounds access in trace_graph_entry at addr ffff88000d717e48 Message-ID: <20150615005704.GA1657@wfg-t540p.sh.intel.com> References: <20150614085559.GB1911@wfg-t540p.sh.intel.com> <20150614123331.GA14645@lerouge> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150614123331.GA14645@lerouge> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2421 Lines: 54 Hi Frederic, On Sun, Jun 14, 2015 at 02:33:32PM +0200, Frederic Weisbecker wrote: > On Sun, Jun 14, 2015 at 04:55:59PM +0800, Fengguang Wu wrote: > > Hi Frederic, > > > > FYI, there are a number more bug messages showing up after this commit > > > > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > > > > commit b30f0e3ffedfa52b1d67a302ae5860c49998e5e2 > > Author: Frederic Weisbecker > > AuthorDate: Tue May 12 16:41:49 2015 +0200 > > Commit: Ingo Molnar > > CommitDate: Tue May 19 08:39:12 2015 +0200 > > > > sched/preempt: Optimize preemption operations on __schedule() callers > > > > __schedule() disables preemption and some of its callers > > (the preempt_schedule*() family) also set PREEMPT_ACTIVE. > > > > So we have two preempt_count() modifications that could be performed > > at once. > > > > Lets remove the preemption disablement from __schedule() and pull > > this responsibility to its callers in order to optimize preempt_count() > > operations in a single place. > > > > Suggested-by: Linus Torvalds > > Signed-off-by: Frederic Weisbecker > > Signed-off-by: Peter Zijlstra (Intel) > > Cc: Peter Zijlstra > > Cc: Thomas Gleixner > > Link: http://lkml.kernel.org/r/1431441711-29753-5-git-send-email-fweisbec@gmail.com > > Signed-off-by: Ingo Molnar > > Do you still see that issue after latest tip:/sched/core. I fixed it a few days ago with: > > 9a92e3dc6ad02208a014d0d8404ebbd697e3d5ef (preempt: Reorganize the notrace definitions a bit) > 4eaca0a887eaee04fc7a3866d0f5b51b34030dfa (preempt: Use preempt_schedule_context() as the official tracing preemption point) > be690035df893385ceaac2323b29be1fb7f2a67f (sched: Make preempt_schedule_context() function-tracing safe) > > But maybe there are other issues remaining. The tip sched/core HEAD looks perfect now -- 1000 boots are all fine except for 2 OOM errors, which look like noises. Thanks, Fengguang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/