From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de ([217.72.192.73]:57817 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753343AbdFVROr (ORCPT ); Thu, 22 Jun 2017 13:14:47 -0400 From: Arnd Bergmann Subject: [PATCH v3 01/11] compiler: introduce noinline_if_stackbloat annotation Date: Thu, 22 Jun 2017 19:13:45 +0200 Message-Id: <20170622171355.267192-2-arnd@arndb.de> In-Reply-To: <20170622171355.267192-1-arnd@arndb.de> References: <20170622171355.267192-1-arnd@arndb.de> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Andrew Morton Cc: kasan-dev@googlegroups.com, Dmitry Vyukov , Alexander Potapenko , Andrey Ryabinin , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Arend van Spriel , Arnd Bergmann , Masahiro Yamada , Michal Marek , Kees Cook , Ingo Molnar , "David S . Miller" , linux-kbuild@vger.kernel.org, Samuel Thibault , Greg Kroah-Hartman , Jiri Slaby 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 219f82f3ec1a..a402c43c07d2 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -412,6 +412,17 @@ 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_if_stackbloat noinline __maybe_unused +#else +#define noinline_if_stackbloat inline +#endif + #ifndef __always_inline #define __always_inline inline #endif -- 2.9.0