From patchwork Tue Apr 23 16:29:29 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Changbin Du X-Patchwork-Id: 10913529 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C62B5112C for ; Tue, 23 Apr 2019 16:39:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B1C18285C9 for ; Tue, 23 Apr 2019 16:39:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A2003287B5; Tue, 23 Apr 2019 16:39:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3F218285C9 for ; Tue, 23 Apr 2019 16:39:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729122AbfDWQjd (ORCPT ); Tue, 23 Apr 2019 12:39:33 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:42503 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729340AbfDWQjI (ORCPT ); Tue, 23 Apr 2019 12:39:08 -0400 Received: by mail-pl1-f195.google.com with SMTP id x15so3443031pln.9; Tue, 23 Apr 2019 09:39:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=lKxrWq0DPWG2/ldiM614YNjWwPB+5TI6uHMpmONkiyA=; b=YFVbYWginTf8h5S0SDoTIVMpULpvCv6OKgMCGQDqwtjfHm8OF/amq8OwLtdHLRayBO BCBf0R5V6HXNxNjhfmUM5Z8W06HJKkSxtFC9rcQDXItwQ7sd1GLz5KFJNjvtjDhcCNIH /RJgCoDHVfa38Ky54CEuElWSUFLSK24t+ehRe+DHGfbWNSN1iU/aWSdUg48jiuxGOvbj PO+h0uNSBBAa78wGa8VboKo+0yvcd/nLNWy6MN9Ac9C8Rb5MdAZOsqGBZ70yJUEdDhP/ SXpMj7o4tL0x2dxs68n7Rjm7Q08Cs0yd7ZrASV1VvAeSQiWYwohAAtRwixx0GvD0zyRc HAyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=lKxrWq0DPWG2/ldiM614YNjWwPB+5TI6uHMpmONkiyA=; b=VbNvtZeiJoEu/zwP2n9DdiB0xhLVMASq3iNZBkVQjxOcWdoZGsFF8Et57ZrXqHT2ap h69SlRsWxfu3uw2+Ysg7NqgE6kTZTWmFuYYlUwAc3larLh5PSMQJnGlG46Jjg3CdMe3G W0ZLVasUQe0UhDbwwIEw6dM345j/Hv0E89V7mBE/01hDKxamKk/fiz1zknVJ+pBgk+WI NFNNsJs5Rk0YEzZFAuqDpFDdFLM7rYKsoggt79nMvuizQ0HFAdAlkDibJhMqi+gh7Ay1 i5EyOmG61RiKkG/HPmWGhEm+bpO/FshTlM6aF8kvS3XwoswVvX6P/b1fYbg1Zt+21gDn uRMw== X-Gm-Message-State: APjAAAVka7yL4Pm2eUyoRGQB+px/FE2Sm6zf4tO7BgaZlPuDYrEbifGN 6EfNFjXm5qdCMQNhNw4zGQM= X-Google-Smtp-Source: APXvYqyyiuJdfDhtn9sySZr3o/D6USw7potnUz8aWY3bi/Zm3hnxy6EcWxCQcMDnbzEmguum4Hqo4Q== X-Received: by 2002:a17:902:e490:: with SMTP id cj16mr27318962plb.156.1556037547194; Tue, 23 Apr 2019 09:39:07 -0700 (PDT) Received: from localhost.localdomain ([104.238.181.70]) by smtp.gmail.com with ESMTPSA id v1sm24364801pff.81.2019.04.23.09.39.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 23 Apr 2019 09:39:06 -0700 (PDT) From: Changbin Du To: Jonathan Corbet Cc: Bjorn Helgaas , rjw@rjwysocki.net, linux-pci@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, fenghua.yu@intel.com, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-gpio@vger.kernel.org, mchehab+samsung@kernel.org, Changbin Du Subject: [PATCH v4 60/63] Documentation: x86: convert x86_64/5level-paging.txt to reST Date: Wed, 24 Apr 2019 00:29:29 +0800 Message-Id: <20190423162932.21428-61-changbin.du@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190423162932.21428-1-changbin.du@gmail.com> References: <20190423162932.21428-1-changbin.du@gmail.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du --- .../{5level-paging.txt => 5level-paging.rst} | 16 +++++++++++----- Documentation/x86/x86_64/index.rst | 1 + 2 files changed, 12 insertions(+), 5 deletions(-) rename Documentation/x86/x86_64/{5level-paging.txt => 5level-paging.rst} (91%) diff --git a/Documentation/x86/x86_64/5level-paging.txt b/Documentation/x86/x86_64/5level-paging.rst similarity index 91% rename from Documentation/x86/x86_64/5level-paging.txt rename to Documentation/x86/x86_64/5level-paging.rst index 2432a5ef86d9..ab88a4514163 100644 --- a/Documentation/x86/x86_64/5level-paging.txt +++ b/Documentation/x86/x86_64/5level-paging.rst @@ -1,5 +1,11 @@ -== Overview == +.. SPDX-License-Identifier: GPL-2.0 +============== +5-level paging +============== + +Overview +======== Original x86-64 was limited by 4-level paing to 256 TiB of virtual address space and 64 TiB of physical address space. We are already bumping into this limit: some vendors offers servers with 64 TiB of memory today. @@ -16,16 +22,17 @@ QEMU 2.9 and later support 5-level paging. Virtual memory layout for 5-level paging is described in Documentation/x86/x86_64/mm.txt -== Enabling 5-level paging == +Enabling 5-level paging +======================= CONFIG_X86_5LEVEL=y enables the feature. Kernel with CONFIG_X86_5LEVEL=y still able to boot on 4-level hardware. In this case additional page table level -- p4d -- will be folded at runtime. -== User-space and large virtual address space == - +User-space and large virtual address space +========================================== On x86, 5-level paging enables 56-bit userspace virtual address space. Not all user space is ready to handle wide addresses. It's known that at least some JIT compilers use higher bits in pointers to encode their @@ -58,4 +65,3 @@ One important case we need to handle here is interaction with MPX. MPX (without MAWA extension) cannot handle addresses above 47-bit, so we need to make sure that MPX cannot be enabled we already have VMA above the boundary and forbid creating such VMAs once MPX is enabled. - diff --git a/Documentation/x86/x86_64/index.rst b/Documentation/x86/x86_64/index.rst index 4b65d29ef459..7b8c82151358 100644 --- a/Documentation/x86/x86_64/index.rst +++ b/Documentation/x86/x86_64/index.rst @@ -10,3 +10,4 @@ x86_64 Support boot-options uefi mm + 5level-paging