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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham 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 922CAC1975A for ; Thu, 12 Mar 2020 15:59:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63408206B7 for ; Thu, 12 Mar 2020 15:59:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="paSD109o" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727714AbgCLP73 (ORCPT ); Thu, 12 Mar 2020 11:59:29 -0400 Received: from mail-ua1-f74.google.com ([209.85.222.74]:48671 "EHLO mail-ua1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727240AbgCLP72 (ORCPT ); Thu, 12 Mar 2020 11:59:28 -0400 Received: by mail-ua1-f74.google.com with SMTP id m2so1027153ual.15 for ; Thu, 12 Mar 2020 08:59:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=OuMVG+rAcmfDAvofKjPIQX+VmSUPtt76BOeSoyVp0P0=; b=paSD109ofywT5exuwClXg1CpSkd67fvla0fLoNnI4B3XWrXO1LZuDc5ckHUaHkQbgW l47wGBvbLvyQrQ6YYYCIxFUyJlInvlCh+aUQlzbO1UW5IFkgkfal8cQ4Qw9n9u4Gnxoh eoF++guRlwiHbzd40JXsZOIhaUsXUnhBek/ux7DqflkZ3AxlGfHIwXhZlhOS+M7KFX6q Dfqvl1cqacnRW59uNGU6Du41IKysk6tl+6pLqEfFOztMPn+/3KmWHlPdVbaVY7jClPbh CDlSvMVEOr/1jfjPMh09yr9uHZfo+g0bmrWNasbg56KJiGAECyck83ntiZGShDqfF7OF 5pcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=OuMVG+rAcmfDAvofKjPIQX+VmSUPtt76BOeSoyVp0P0=; b=abo9a1XACOIE9YGa7WjvMHlEC2uo5HoYYj4DRTwkZCza2idTIUHQs3BfsIqWrjbv5E ki1lBWUkl/sO4703LUVzLv8vSAiORd65Qxtl50t6emuWkVpkVYmUFCFDV5iVA53tvPh2 VbsUPUhLxNYrkIKJocgRnmJ7tDlKMhKZ6lEUWgChhrvntq0ob5lblbHwodH6BgvxVy6Y itXs34c5KT5cMauZYA4RH8RMWyRXyxkDNwmF7HIA3UmPrO4X7r4HZbBy7275BY7PZ96I p+z6bKkHyPvJNejgGyelV5wne85YaVaMRz/ntTA8facMXj/gyC/fgPJ6UfvU+XOsUH8A j3zA== X-Gm-Message-State: ANhLgQ2qXuOr5shz0ewvx/qMPF5nF0HJ8/7tc+FOCPTpja29aH0JrsQ9 1flR+6FzudEXQ07hqfnhYSYzkFoDnRA= X-Google-Smtp-Source: ADFU+vuX7lmrwStgO00QF2whBWVzujCp6g4AqJSb1iqI9dt6fK6BzDUAqsvOBASiE2eLCEGcMWhMcNAeQrU= X-Received: by 2002:a1f:2c08:: with SMTP id s8mr5746912vks.53.1584028767311; Thu, 12 Mar 2020 08:59:27 -0700 (PDT) Date: Thu, 12 Mar 2020 16:59:20 +0100 Message-Id: <20200312155920.50067-1-glider@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.25.1.481.gfbce0eb801-goog Subject: [PATCH] arm64: define __alloc_zeroed_user_highpage From: glider@google.com To: catalin.marinas@arm.com, will.deacon@arm.com, mark.rutland@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, keescook@chromium.org, akpm@linux-foundation.org, Alexander Potapenko Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When running the kernel with init_on_alloc=1, calling the default implementation of __alloc_zeroed_user_highpage() from include/linux/highmem.h leads to double-initialization of the allocated page (first by the page allocator, then by clear_user_page(). Calling alloc_page_vma() with __GFP_ZERO, similarly to e.g. x86, seems to be enough to ensure the user page is zeroed only once. Signed-off-by: Alexander Potapenko --- arch/arm64/include/asm/page.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h index d39ddb258a049..75d6cd23a6790 100644 --- a/arch/arm64/include/asm/page.h +++ b/arch/arm64/include/asm/page.h @@ -21,6 +21,10 @@ extern void __cpu_copy_user_page(void *to, const void *from, extern void copy_page(void *to, const void *from); extern void clear_page(void *to); +#define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \ + alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr) +#define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE + #define clear_user_page(addr,vaddr,pg) __cpu_clear_user_page(addr, vaddr) #define copy_user_page(to,from,vaddr,pg) __cpu_copy_user_page(to, from, vaddr) -- 2.25.1.481.gfbce0eb801-goog