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=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 07EC3C433E6 for ; Fri, 5 Feb 2021 23:47:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9FFF064FDE for ; Fri, 5 Feb 2021 23:47:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231320AbhBEXpw (ORCPT ); Fri, 5 Feb 2021 18:45:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232495AbhBEORn (ORCPT ); Fri, 5 Feb 2021 09:17:43 -0500 Received: from mail-lf1-x14a.google.com (mail-lf1-x14a.google.com [IPv6:2a00:1450:4864:20::14a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C664DC061222 for ; Fri, 5 Feb 2021 07:47:17 -0800 (PST) Received: by mail-lf1-x14a.google.com with SMTP id c13so4129466lfm.4 for ; Fri, 05 Feb 2021 07:47:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=PREZUncIqPTZICTNMYAhqfkQODhaZIF+0hFoo18paHE=; b=konF6v6BnN243u57JzN3b95VF77A0Qj1x+GlllUtiuD8VnfG6AL7oWEx03hrBfwRj8 aYE1+nYx+DzgmpLmNYFC4bk1hHc+2drX7wYZY0+sbzyQVai8e5ZWESQ57O8F1XO3Fv6O A80n2LSxNhH5p14Cz9+YH0Sh1eL3HyDaJn+FVtAuQU8Xbu8iNidaUe7LCekS99pT+1hH Oou+pgF6FEv+zEFiwfwff+OOi0SNFMv97nl9nABkE7clP+7820Ppjz1MdS8a+Ewetltv HG/rue7AEX/E9aasLQ/JlhnWPPmj1ImsCgoBRb7fVjcCHtXw3ovNJFB74SuoOphoobHx g20Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=PREZUncIqPTZICTNMYAhqfkQODhaZIF+0hFoo18paHE=; b=XoHNSUMKErGBPZczYxTwXqav4UmbuV8jdx87w3Xsk+WATqur/rKYW/0Li3dQKAydQU +DSSfGfNEg1cbLZ6yI/2vr3X5+ggUfnnjNmqluQJXOGf1KLYk5LiHmMe+SOnVijrN49h ZLGu8Lh0BBAUftAxOsKPn0T7yYN/8BGuyY8BIj2zcn3RV4i9XZhskDALMfbl6PVXNwq9 b03ArRUc4jvkvZ46kuycMR+9aCAYFz2eNW2ZbLpauNYGe3YTdQ5e4mPax+AMpcvCSTcO JfYNaqx7UMrl3UjMr2RoNDJI8JCfhhvP4HaaoJKhkOaKOiZ4v2k800fjHAfJgZiAnVZx hL2A== X-Gm-Message-State: AOAM532g3PqJ/ER4LMV3Tqn5ylSMvzz7nLZsLCgi19U2qzXb8WEOtkzy KAMzvtQ25ra7sTOGPUh+Yu7QysmHiGnnq4F6 X-Google-Smtp-Source: ABdhPJxLyOBedtBSH56Km8M+KSKGSY+TJY33YcVxBP++XHc1sb/s8ursYOVubg9JIcGS4jhcauoOBzI04W3jHs91 Sender: "andreyknvl via sendgmr" X-Received: from andreyknvl3.muc.corp.google.com ([2a00:79e0:15:13:edb8:b79c:2e20:e531]) (user=andreyknvl job=sendgmr) by 2002:a17:906:8611:: with SMTP id o17mr4584420ejx.145.1612539582294; Fri, 05 Feb 2021 07:39:42 -0800 (PST) Date: Fri, 5 Feb 2021 16:39:11 +0100 In-Reply-To: Message-Id: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH v2 10/12] arm64: kasan: simplify and inline MTE functions From: Andrey Konovalov To: Andrew Morton , Catalin Marinas , Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver Cc: Will Deacon , Andrey Ryabinin , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This change provides a simpler implementation of mte_get_mem_tag(), mte_get_random_tag(), and mte_set_mem_tag_range(). Simplifications include removing system_supports_mte() checks as these functions are onlye called from KASAN runtime that had already checked system_supports_mte(). Besides that, size and address alignment checks are removed from mte_set_mem_tag_range(), as KASAN now does those. This change also moves these functions into the asm/mte-kasan.h header and implements mte_set_mem_tag_range() via inline assembly to avoid unnecessary functions calls. Reviewed-by: Catalin Marinas Co-developed-by: Vincenzo Frascino Signed-off-by: Vincenzo Frascino Signed-off-by: Andrey Konovalov --- arch/arm64/include/asm/cache.h | 1 - arch/arm64/include/asm/kasan.h | 1 + arch/arm64/include/asm/mte-def.h | 2 + arch/arm64/include/asm/mte-kasan.h | 65 ++++++++++++++++++++++++++---- arch/arm64/include/asm/mte.h | 2 - arch/arm64/kernel/mte.c | 46 --------------------- arch/arm64/lib/mte.S | 16 -------- 7 files changed, 60 insertions(+), 73 deletions(-) diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h index 77cbbe3625f2..a074459f8f2f 100644 --- a/arch/arm64/include/asm/cache.h +++ b/arch/arm64/include/asm/cache.h @@ -6,7 +6,6 @@ #define __ASM_CACHE_H #include -#include #define CTR_L1IP_SHIFT 14 #define CTR_L1IP_MASK 3 diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h index 0aaf9044cd6a..12d5f47f7dbe 100644 --- a/arch/arm64/include/asm/kasan.h +++ b/arch/arm64/include/asm/kasan.h @@ -6,6 +6,7 @@ #include #include +#include #include #define arch_kasan_set_tag(addr, tag) __tag_set(addr, tag) diff --git a/arch/arm64/include/asm/mte-def.h b/arch/arm64/include/asm/mte-def.h index 2d73a1612f09..cf241b0f0a42 100644 --- a/arch/arm64/include/asm/mte-def.h +++ b/arch/arm64/include/asm/mte-def.h @@ -11,4 +11,6 @@ #define MTE_TAG_SIZE 4 #define MTE_TAG_MASK GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT) +#define __MTE_PREAMBLE ARM64_ASM_PREAMBLE ".arch_extension memtag\n" + #endif /* __ASM_MTE_DEF_H */ diff --git a/arch/arm64/include/asm/mte-kasan.h b/arch/arm64/include/asm/mte-kasan.h index 8ad981069afb..13be3afc37ac 100644 --- a/arch/arm64/include/asm/mte-kasan.h +++ b/arch/arm64/include/asm/mte-kasan.h @@ -11,11 +11,14 @@ #include +#ifdef CONFIG_ARM64_MTE + /* - * The functions below are meant to be used only for the - * KASAN_HW_TAGS interface defined in asm/memory.h. + * These functions are meant to be only used from KASAN runtime through + * the arch_*() interface defined in asm/memory.h. + * These functions don't include system_supports_mte() checks, + * as KASAN only calls them when MTE is supported and enabled. */ -#ifdef CONFIG_ARM64_MTE static inline u8 mte_get_ptr_tag(void *ptr) { @@ -25,9 +28,54 @@ static inline u8 mte_get_ptr_tag(void *ptr) return tag; } -u8 mte_get_mem_tag(void *addr); -u8 mte_get_random_tag(void); -void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag); +/* Get allocation tag for the address. */ +static inline u8 mte_get_mem_tag(void *addr) +{ + asm(__MTE_PREAMBLE "ldg %0, [%0]" + : "+r" (addr)); + + return mte_get_ptr_tag(addr); +} + +/* Generate a random tag. */ +static inline u8 mte_get_random_tag(void) +{ + void *addr; + + asm(__MTE_PREAMBLE "irg %0, %0" + : "+r" (addr)); + + return mte_get_ptr_tag(addr); +} + +/* + * Assign allocation tags for a region of memory based on the pointer tag. + * Note: The address must be non-NULL and MTE_GRANULE_SIZE aligned and + * size must be non-zero and MTE_GRANULE_SIZE aligned. + */ +static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag) +{ + u64 curr, end; + + if (!size) + return; + + curr = (u64)__tag_set(addr, tag); + end = curr + size; + + do { + /* + * 'asm volatile' is required to prevent the compiler to move + * the statement outside of the loop. + */ + asm volatile(__MTE_PREAMBLE "stg %0, [%0]" + : + : "r" (curr) + : "memory"); + + curr += MTE_GRANULE_SIZE; + } while (curr != end); +} void mte_enable_kernel_sync(void); void mte_enable_kernel_async(void); @@ -47,13 +95,14 @@ static inline u8 mte_get_mem_tag(void *addr) { return 0xFF; } + static inline u8 mte_get_random_tag(void) { return 0xFF; } -static inline void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag) + +static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag) { - return addr; } static inline void mte_enable_kernel_sync(void) diff --git a/arch/arm64/include/asm/mte.h b/arch/arm64/include/asm/mte.h index 237bb2f7309d..43169b978cd3 100644 --- a/arch/arm64/include/asm/mte.h +++ b/arch/arm64/include/asm/mte.h @@ -8,8 +8,6 @@ #include #include -#define __MTE_PREAMBLE ARM64_ASM_PREAMBLE ".arch_extension memtag\n" - #ifndef __ASSEMBLY__ #include diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index 7763ac1f2917..8b27b70e1aac 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include @@ -88,51 +87,6 @@ int memcmp_pages(struct page *page1, struct page *page2) return ret; } -u8 mte_get_mem_tag(void *addr) -{ - if (!system_supports_mte()) - return 0xFF; - - asm(__MTE_PREAMBLE "ldg %0, [%0]" - : "+r" (addr)); - - return mte_get_ptr_tag(addr); -} - -u8 mte_get_random_tag(void) -{ - void *addr; - - if (!system_supports_mte()) - return 0xFF; - - asm(__MTE_PREAMBLE "irg %0, %0" - : "+r" (addr)); - - return mte_get_ptr_tag(addr); -} - -void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag) -{ - void *ptr = addr; - - if ((!system_supports_mte()) || (size == 0)) - return addr; - - /* Make sure that size is MTE granule aligned. */ - WARN_ON(size & (MTE_GRANULE_SIZE - 1)); - - /* Make sure that the address is MTE granule aligned. */ - WARN_ON((u64)addr & (MTE_GRANULE_SIZE - 1)); - - tag = 0xF0 | tag; - ptr = (void *)__tag_set(ptr, tag); - - mte_assign_mem_tag_range(ptr, size); - - return ptr; -} - void mte_init_tags(u64 max_tag) { static bool gcr_kernel_excl_initialized; diff --git a/arch/arm64/lib/mte.S b/arch/arm64/lib/mte.S index 9e1a12e10053..351537c12f36 100644 --- a/arch/arm64/lib/mte.S +++ b/arch/arm64/lib/mte.S @@ -149,19 +149,3 @@ SYM_FUNC_START(mte_restore_page_tags) ret SYM_FUNC_END(mte_restore_page_tags) - -/* - * Assign allocation tags for a region of memory based on the pointer tag - * x0 - source pointer - * x1 - size - * - * Note: The address must be non-NULL and MTE_GRANULE_SIZE aligned and - * size must be non-zero and MTE_GRANULE_SIZE aligned. - */ -SYM_FUNC_START(mte_assign_mem_tag_range) -1: stg x0, [x0] - add x0, x0, #MTE_GRANULE_SIZE - subs x1, x1, #MTE_GRANULE_SIZE - b.gt 1b - ret -SYM_FUNC_END(mte_assign_mem_tag_range) -- 2.30.0.365.g02bc693789-goog