From patchwork Thu Nov 25 08:23:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 12638659 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99BF0C433F5 for ; Thu, 25 Nov 2021 08:27:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3E23A6B0082; Thu, 25 Nov 2021 03:24:21 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 391B56B0083; Thu, 25 Nov 2021 03:24:21 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 259756B0085; Thu, 25 Nov 2021 03:24:21 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0215.hostedemail.com [216.40.44.215]) by kanga.kvack.org (Postfix) with ESMTP id 183FA6B0082 for ; Thu, 25 Nov 2021 03:24:21 -0500 (EST) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id CBEE2812E61A for ; Thu, 25 Nov 2021 08:24:10 +0000 (UTC) X-FDA: 78846765060.31.30845AF Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by imf03.hostedemail.com (Postfix) with ESMTP id 0A7AB30000BE for ; Thu, 25 Nov 2021 08:24:06 +0000 (UTC) Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4J09rW6S39z9sT2; Thu, 25 Nov 2021 09:23:55 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id XMRS3j_NWamp; Thu, 25 Nov 2021 09:23:55 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4J09rM65d2z9sSx; Thu, 25 Nov 2021 09:23:47 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id C10B98B77B; Thu, 25 Nov 2021 09:23:47 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id AVbd-du857Au; Thu, 25 Nov 2021 09:23:47 +0100 (CET) Received: from PO20335.IDSI0.si.c-s.fr (unknown [192.168.203.227]) by messagerie.si.c-s.fr (Postfix) with ESMTP id EA9D18B77D; Thu, 25 Nov 2021 09:23:46 +0100 (CET) Received: from PO20335.IDSI0.si.c-s.fr (localhost [127.0.0.1]) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.16.1) with ESMTPS id 1AP8NdTl086380 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Thu, 25 Nov 2021 09:23:39 +0100 Received: (from chleroy@localhost) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.17.1/Submit) id 1AP8NdJv086379; Thu, 25 Nov 2021 09:23:39 +0100 X-Authentication-Warning: PO20335.IDSI0.si.c-s.fr: chleroy set sender to christophe.leroy@csgroup.eu using -f From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , alex@ghiti.fr Cc: Christophe Leroy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org Subject: [PATCH v2 9/9] powerpc: Simplify and move arch_randomize_brk() Date: Thu, 25 Nov 2021 09:23:31 +0100 Message-Id: <4c5a2b18774552c2226573f7069ffeee71ad77cb.1637828367.git.christophe.leroy@csgroup.eu> X-Mailer: git-send-email 2.33.1 In-Reply-To: References: MIME-Version: 1.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1637828609; l=3773; s=20211009; h=from:subject:message-id; bh=uDMNxxQ2lNaP63d0uIkwxjHDa3IfpqMt7N58uCcNJIM=; b=Tn0UK+dlcWXuMeocBLofKxqdqjcqqlONZwe8JqKJQQdMw2fNGRYyBDArfjOd0qDjjxzE/MdEcNal mGjmrut4D9s2VJQyx/hSgIpb1ekBl7TeIwmTiwgx5PnBeFi685v2 X-Developer-Key: i=christophe.leroy@csgroup.eu; a=ed25519; pk=HIzTzUj91asvincQGOFx6+ZF5AoUuP9GdOtQChs7Mm0= X-Stat-Signature: my1wc83u5okpopzo8roe4q3b7w3ryxtd X-Rspamd-Queue-Id: 0A7AB30000BE X-Rspamd-Server: rspam07 Authentication-Results: imf03.hostedemail.com; dkim=none; spf=pass (imf03.hostedemail.com: domain of christophe.leroy@csgroup.eu designates 93.17.235.10 as permitted sender) smtp.mailfrom=christophe.leroy@csgroup.eu; dmarc=none X-HE-Tag: 1637828646-641029 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: arch_randomize_brk() is only needed for hash on book3s/64, for other platforms the one provided by the default mmap layout is good enough. Move it to hash_utils.c and use randomize_page() like the generic one. And properly opt out the radix case instead of making an assumption on mmu_highuser_ssize. Also change to a 32M range like most other architectures instead of 8M. Signed-off-by: Christophe Leroy Reported-by: kernel test robot Reported-by: kernel test robot --- v2: New --- arch/powerpc/kernel/process.c | 40 --------------------------- arch/powerpc/mm/book3s64/hash_utils.c | 18 ++++++++++++ include/linux/sizes.h | 2 ++ 3 files changed, 20 insertions(+), 40 deletions(-) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 406d7ee9e322..f1f2f17543d6 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2274,43 +2274,3 @@ unsigned long arch_align_stack(unsigned long sp) sp -= get_random_int() & ~PAGE_MASK; return sp & ~0xf; } - -static inline unsigned long brk_rnd(void) -{ - unsigned long rnd = 0; - - /* 8MB for 32bit, 1GB for 64bit */ - if (is_32bit_task()) - rnd = (get_random_long() % (1UL<<(23-PAGE_SHIFT))); - else - rnd = (get_random_long() % (1UL<<(30-PAGE_SHIFT))); - - return rnd << PAGE_SHIFT; -} - -unsigned long arch_randomize_brk(struct mm_struct *mm) -{ - unsigned long base = mm->brk; - unsigned long ret; - -#ifdef CONFIG_PPC_BOOK3S_64 - /* - * If we are using 1TB segments and we are allowed to randomise - * the heap, we can put it above 1TB so it is backed by a 1TB - * segment. Otherwise the heap will be in the bottom 1TB - * which always uses 256MB segments and this may result in a - * performance penalty. We don't need to worry about radix. For - * radix, mmu_highuser_ssize remains unchanged from 256MB. - */ - if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T)) - base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T); -#endif - - ret = PAGE_ALIGN(base + brk_rnd()); - - if (ret < mm->brk) - return mm->brk; - - return ret; -} - diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 1d09d4aeddbf..3521fad6a479 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -2072,3 +2073,20 @@ void __init print_system_hash_info(void) if (htab_hash_mask) pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask); } + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + /* + * If we are using 1TB segments and we are allowed to randomise + * the heap, we can put it above 1TB so it is backed by a 1TB + * segment. Otherwise the heap will be in the bottom 1TB + * which always uses 256MB segments and this may result in a + * performance penalty. + */ + if (is_32bit_task()) + return randomize_page(mm->brk, SZ_32M); + else if (!radix_enabled() && mmu_highuser_ssize == MMU_SEGSIZE_1T) + return randomize_page(max_t(unsigned long, mm->brk, SZ_1T), SZ_1G); + else + return randomize_page(mm->brk, SZ_1G); +} diff --git a/include/linux/sizes.h b/include/linux/sizes.h index 1ac79bcee2bb..84aa448d8bb3 100644 --- a/include/linux/sizes.h +++ b/include/linux/sizes.h @@ -47,6 +47,8 @@ #define SZ_8G _AC(0x200000000, ULL) #define SZ_16G _AC(0x400000000, ULL) #define SZ_32G _AC(0x800000000, ULL) + +#define SZ_1T _AC(0x10000000000, ULL) #define SZ_64T _AC(0x400000000000, ULL) #endif /* __LINUX_SIZES_H__ */