From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751399AbcBLTqk (ORCPT ); Fri, 12 Feb 2016 14:46:40 -0500 Received: from mail-pa0-f51.google.com ([209.85.220.51]:33539 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751103AbcBLTqj (ORCPT ); Fri, 12 Feb 2016 14:46:39 -0500 Subject: Re: [PATCH] trace, kasan: silence Kasan warning in check_stack To: Steven Rostedt References: <1454956782-5944-1-git-send-email-yang.shi@linaro.org> <20160212143547.703d9e9f@gandalf.local.home> Cc: aryabinin@virtuozzo.com, mingo@redhat.com, linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org From: "Shi, Yang" Message-ID: <56BE369D.6090007@linaro.org> Date: Fri, 12 Feb 2016 11:46:37 -0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160212143547.703d9e9f@gandalf.local.home> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/12/2016 11:35 AM, Steven Rostedt wrote: > On Mon, 8 Feb 2016 10:39:42 -0800 > Yang Shi wrote: > >> >> Signed-off-by: Yang Shi >> --- >> kernel/trace/trace_stack.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c >> index 202df6c..61e5e1e 100644 >> --- a/kernel/trace/trace_stack.c >> +++ b/kernel/trace/trace_stack.c >> @@ -156,7 +156,7 @@ check_stack(unsigned long ip, unsigned long *stack) >> for (; p < top && i < stack_trace_max.nr_entries; p++) { >> if (stack_dump_trace[i] == ULONG_MAX) >> break; >> - if (*p == stack_dump_trace[i]) { > > Can you add a comment explaining this. Something like: > > /* > * The READ_ONCE_NOCHECK() is used to let KASAN know that > * this is not an stack-out-of-bounds error. > */ Sure, will add in v2. Thanks, Yang > > Thanks, > > -- Steve > >> + if ((READ_ONCE_NOCHECK(*p)) == stack_dump_trace[i]) { >> stack_dump_trace[x] = stack_dump_trace[i++]; >> this_size = stack_trace_index[x++] = >> (top - p) * sizeof(unsigned long); >