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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B86ADC7618F for ; Thu, 18 Jul 2019 16:18:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A88121852 for ; Thu, 18 Jul 2019 16:18:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730195AbfGRQSZ (ORCPT ); Thu, 18 Jul 2019 12:18:25 -0400 Received: from relay.sw.ru ([185.231.240.75]:41000 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726649AbfGRQSZ (ORCPT ); Thu, 18 Jul 2019 12:18:25 -0400 Received: from [172.16.25.12] by relay.sw.ru with esmtp (Exim 4.92) (envelope-from ) id 1ho96r-000845-Ln; Thu, 18 Jul 2019 19:18:21 +0300 Subject: Re: [PATCH] kasan: push back KASAN_STACK detection to clang-10 To: Arnd Bergmann , Andrew Morton Cc: Qian Cai , Mark Brown , Vasily Gorbik , Andrey Konovalov , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com References: <20190718141503.3258299-1-arnd@arndb.de> From: Andrey Ryabinin Message-ID: <0ee5952b-5a76-c8a5-a30a-ee3c46a54814@virtuozzo.com> Date: Thu, 18 Jul 2019 19:18:28 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190718141503.3258299-1-arnd@arndb.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/18/19 5:14 PM, Arnd Bergmann wrote: > asan-stack mode still uses dangerously large kernel stacks of > tens of kilobytes in some drivers, and it does not seem that anyone > is working on the clang bug. > > Let's push this back to clang-10 for now so users don't run into > this by accident, and we can test-build allmodconfig kernels using > clang-9 without drowning in warnings. > > Link: https://bugs.llvm.org/show_bug.cgi?id=38809 > Fixes: 6baec880d7a5 ("kasan: turn off asan-stack for clang-8 and earlier") > Signed-off-by: Arnd Bergmann > --- > lib/Kconfig.kasan | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan > index 4fafba1a923b..2f260bb63d77 100644 > --- a/lib/Kconfig.kasan > +++ b/lib/Kconfig.kasan > @@ -106,7 +106,7 @@ endchoice > > config KASAN_STACK_ENABLE > bool "Enable stack instrumentation (unsafe)" if CC_IS_CLANG && !COMPILE_TEST > - default !(CLANG_VERSION < 90000) > + default !(CLANG_VERSION < 100000) Wouldn't be better to make this thing for any clang version? And only when the bug is finally fixed, specify the clang version which can enable this safely. > depends on KASAN > help > The LLVM stack address sanitizer has a know problem that >