From patchwork Mon Nov 29 14:19:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 12644783 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 9EF2BC433F5 for ; Mon, 29 Nov 2021 14:24:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C8F136B0081; Mon, 29 Nov 2021 09:21:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C3F276B0082; Mon, 29 Nov 2021 09:21:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B06066B0083; Mon, 29 Nov 2021 09:21:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0001.hostedemail.com [216.40.44.1]) by kanga.kvack.org (Postfix) with ESMTP id A27AB6B0081 for ; Mon, 29 Nov 2021 09:21:32 -0500 (EST) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 6DB3384D10 for ; Mon, 29 Nov 2021 14:21:22 +0000 (UTC) X-FDA: 78862180362.07.1BBB72B Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by imf28.hostedemail.com (Postfix) with ESMTP id 1CFC4900062E for ; Mon, 29 Nov 2021 14:19:59 +0000 (UTC) Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4J2nYF1bMZz9sSk; Mon, 29 Nov 2021 15:19:45 +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 tMFiFXXY5YB5; Mon, 29 Nov 2021 15:19:45 +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 4J2nY40f7dz9sT0; Mon, 29 Nov 2021 15:19:36 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 041308B7B8; Mon, 29 Nov 2021 15:19:36 +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 UV2pae6Rn5Ai; Mon, 29 Nov 2021 15:19:35 +0100 (CET) Received: from PO20335.IDSI0.si.c-s.fr (unknown [172.25.230.108]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 99A478B7AE; Mon, 29 Nov 2021 15:19:35 +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 1ATEJSE5959572 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Mon, 29 Nov 2021 15:19:28 +0100 Received: (from chleroy@localhost) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.17.1/Submit) id 1ATEJSYd959571; Mon, 29 Nov 2021 15:19:28 +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 v3 06/10] mm: Allow arch specific arch_randomize_brk() with CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT Date: Mon, 29 Nov 2021 15:19:20 +0100 Message-Id: <6e242e505c2f5e528a6217b3462fcb8465da4c2e.1638195388.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=1638195562; l=1197; s=20211009; h=from:subject:message-id; bh=ieZDasKgJMLzWvasijn2/EaRxhxrIxH0kApK0npELEI=; b=3eK4/LkHASlZxwojwvJ1UN52PWpkOtHvR3vlHdoDCYaqY6d/VpBawjWNRsOkCxwAkUd49Sj3A/ts 5A0HHlcmBKX5yWXuO97w8QhE07W7ze09M2no9XLRX3Tc1GcSNUlK X-Developer-Key: i=christophe.leroy@csgroup.eu; a=ed25519; pk=HIzTzUj91asvincQGOFx6+ZF5AoUuP9GdOtQChs7Mm0= X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 1CFC4900062E X-Stat-Signature: 4q4cxkp35yan4w5oje8b7rkprsppgomc Authentication-Results: imf28.hostedemail.com; dkim=none; spf=pass (imf28.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: 1638195599-626013 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: Commit e7142bf5d231 ("arm64, mm: make randomization selected by generic topdown mmap layout") introduced a default version of arch_randomize_brk() provided when CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT is selected. powerpc could select CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT but needs to provide its own arch_randomize_brk(). In order to allow that, define generic version of arch_randomize_brk() as a __weak symbol. Cc: Alexandre Ghiti Signed-off-by: Christophe Leroy --- v2: Make the generic version of it a __weak symbol instead of a messy play with CONFIG_ items. --- mm/util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/util.c b/mm/util.c index 741ba32a43ac..46d1a2dd7a32 100644 --- a/mm/util.c +++ b/mm/util.c @@ -344,7 +344,7 @@ unsigned long randomize_stack_top(unsigned long stack_top) } #ifdef CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT -unsigned long arch_randomize_brk(struct mm_struct *mm) +unsigned long __weak arch_randomize_brk(struct mm_struct *mm) { /* Is the current task 32bit ? */ if (!IS_ENABLED(CONFIG_64BIT) || is_compat_task())