From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 3EEAA6B02C3 for ; Tue, 8 May 2018 13:21:19 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id w14-v6so21773974wrk.22 for ; Tue, 08 May 2018 10:21:19 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id o18-v6sor12164780wrc.40.2018.05.08.10.21.17 for (Google Transport Security); Tue, 08 May 2018 10:21:18 -0700 (PDT) From: Andrey Konovalov Subject: [PATCH v1 04/16] khwasan, arm64: adjust shadow size for CONFIG_KASAN_HW Date: Tue, 8 May 2018 19:20:50 +0200 Message-Id: <3dc2407877072a1f14154928a7ba542b4f5a9c05.1525798754.git.andreyknvl@google.com> In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Jonathan Corbet , Catalin Marinas , Will Deacon , Christopher Li , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Masahiro Yamada , Michal Marek , Andrey Konovalov , Mark Rutland , Nick Desaulniers , Yury Norov , Marc Zyngier , Kristina Martsenko , Suzuki K Poulose , Punit Agrawal , Dave Martin , Ard Biesheuvel , James Morse , Michael Weiser , Julien Thierry , Tyler Baicar , "Eric W . Biederman" , Thomas Gleixner , Ingo Molnar , Kees Cook , Sandipan Das , David Woodhouse , Paul Lawrence , Herbert Xu , Josh Poimboeuf , Geert Uytterhoeven , Tom Lendacky , Arnd Bergmann , Dan Williams , Michal Hocko , Jan Kara , Ross Zwisler , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Matthew Wilcox , "Kirill A . Shutemov" , Souptick Joarder , Hugh Dickins , Davidlohr Bueso , Greg Kroah-Hartman , Philippe Ombredanne , Kate Stewart , Laura Abbott , Boris Brezillon , Vlastimil Babka , Pintu Agarwal , Doug Berger , Anshuman Khandual , Mike Rapoport , Mel Gorman , Pavel Tatashin , Tetsuo Handa , kasan-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sparse@vger.kernel.org, linux-mm@kvack.org, linux-kbuild@vger.kernel.org Cc: Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Kees Cook , Jann Horn , Mark Brand , Chintan Pandya KWHASAN uses 1 shadow byte for 16 bytes of kernel memory, so it requires 1/16th of the kernel virtual address space for the shadow memory. This commit sets KASAN_SHADOW_SCALE_SHIFT to 4 when KHWASAN is enabled. Signed-off-by: Andrey Konovalov --- arch/arm64/Makefile | 2 +- arch/arm64/include/asm/memory.h | 13 +++++++++---- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 87f7d2f9f17c..99c9649c57b1 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -99,7 +99,7 @@ endif # KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT)) # - (1 << (64 - KASAN_SHADOW_SCALE_SHIFT)) # in 32-bit arithmetic -KASAN_SHADOW_SCALE_SHIFT := 3 +KASAN_SHADOW_SCALE_SHIFT := $(if $(CONFIG_KASAN_HW), 4, 3) KASAN_SHADOW_OFFSET := $(shell printf "0x%08x00000000\n" $$(( \ (0xffffffff & (-1 << ($(CONFIG_ARM64_VA_BITS) - 32))) \ + (1 << ($(CONFIG_ARM64_VA_BITS) - 32 - $(KASAN_SHADOW_SCALE_SHIFT))) \ diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 49d99214f43c..6d084431b7f7 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -74,12 +74,17 @@ #define KERNEL_END _end /* - * KASAN requires 1/8th of the kernel virtual address space for the shadow - * region. KASAN can bloat the stack significantly, so double the (minimum) - * stack size when KASAN is in use. + * KASAN and KHWASAN require 1/8th and 1/16th of the kernel virtual address + * space for the shadow region respectively. They can bloat the stack + * significantly, so double the (minimum) stack size when they are in use. */ -#ifdef CONFIG_KASAN +#ifdef CONFIG_KASAN_GENERIC #define KASAN_SHADOW_SCALE_SHIFT 3 +#endif +#ifdef CONFIG_KASAN_HW +#define KASAN_SHADOW_SCALE_SHIFT 4 +#endif +#ifdef CONFIG_KASAN #define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT)) #define KASAN_THREAD_SHIFT 1 #else -- 2.17.0.441.gb46fe60e1d-goog