Return-path: Received: from mout.kundenserver.de ([212.227.126.131]:61372 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754117AbdCBRLS (ORCPT ); Thu, 2 Mar 2017 12:11:18 -0500 From: Arnd Bergmann To: kasan-dev@googlegroups.com Cc: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-wireless@vger.kernel.org, kernel-build-reports@lists.linaro.org, "David S . Miller" , Arnd Bergmann Subject: [PATCH 01/26] compiler: introduce noinline_for_kasan annotation Date: Thu, 2 Mar 2017 17:38:09 +0100 Message-Id: <20170302163834.2273519-2-arnd@arndb.de> (sfid-20170302_181354_742297_2AECBEC1) In-Reply-To: <20170302163834.2273519-1-arnd@arndb.de> References: <20170302163834.2273519-1-arnd@arndb.de> Sender: linux-wireless-owner@vger.kernel.org List-ID: When CONFIG_KASAN is set, we can run into some code that uses incredible amounts of kernel stack: drivers/staging/dgnc/dgnc_neo.c:1056:1: error: the frame size of 11112 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] drivers/media/i2c/cx25840/cx25840-core.c:4960:1: error: the frame size of 94000 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] drivers/media/dvb-frontends/stv090x.c:3430:1: error: the frame size of 5312 bytes is larger than 3072 bytes [-Werror=frame-larger-than=] This happens when a sanitizer uses stack memory each time an inline function gets called. This introduces a new annotation for those functions to make them either 'inline' or 'noinline' dependning on the CONFIG_KASAN symbol. Signed-off-by: Arnd Bergmann --- include/linux/compiler.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index f8110051188f..56b90897a459 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -416,6 +416,17 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s */ #define noinline_for_stack noinline +/* + * CONFIG_KASAN can lead to extreme stack usage with certain patterns when + * one function gets inlined many times and each instance requires a stack + * ckeck. + */ +#ifdef CONFIG_KASAN +#define noinline_for_kasan noinline __maybe_unused +#else +#define noinline_for_kasan inline +#endif + #ifndef __always_inline #define __always_inline inline #endif -- 2.9.0