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Jan Beulich
dbded5568e
On NUMA systems, where we try to use node local memory for the basic control structures of the buddy allocator, this special case needs to take into consideration a possible address width limit placed on the Xen heap. In turn this (but also other, more abstract considerations) requires that xenheap_max_mfn() not be called more than once (at most we might permit it to be called a second time with a larger value than was passed the first time), and be called only before calling end_boot_allocator(). While inspecting all the involved code, a couple of off-by-one issues were found (and are being corrected here at once): - arch_init_memory() cleared one too many page table slots - the highmem_start based invocation of xenheap_max_mfn() passed too big a value - xenheap_max_mfn() calculated the wrong bit count in edge cases Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> xen/arm64: do not (incorrectly) limit size of xenheap The commit88e3ed6164"x86/NUMA: make init_node_heap() respect Xen heap limit" breaks boot on the arm64 board X-Gene. The xenheap bits variable is used to know the last RAM MFN always mapped in Xen virtual memory. If the value is 0, it means that all the memory is always mapped in Xen virtual memory. On X-gene the RAM bank resides above 128GB and last xenheap MFN is 0x4400000. With the new way to calculate the number of bits, xenheap_bits will be equal to 38 bits. This will result to hide all the RAM and the impossibility to allocate xenheap memory. Given that aarch64 have always all the memory mapped in Xen virtual memory, it's not necessary to call xenheap_max_mfn which set the number of bits. Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Julien Grall <julien.grall@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> master commit:88e3ed6164master date: 2015-09-01 14:02:57 +0200 master commit:0a7167d9b2master date: 2015-09-04 14:58:07 +0100
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http://www.xen.org/
What is Xen?
============
Xen is a Virtual Machine Monitor (VMM) originally developed by the
Systems Research Group of the University of Cambridge Computer
Laboratory, as part of the UK-EPSRC funded XenoServers project. Xen
is freely-distributable Open Source software, released under the GNU
GPL. Since its initial public release, Xen has grown a large
development community, spearheaded by xen.org (http://www.xen.org).
The 4.4 release offers a number of improvements, including solid
support for libvirt running on libxl, a new scalable event channel
interface, improved flexibility for driver domains, an experimental
"PVH" virtualization mode, improved kexec support, and improved
support for SPICE clients. Additionally, the ARM platform has had a
number of improvements. The most important of these is that the
hypervisor ABIs for both arm32 and arm64 have been declared stable.
Additionally, many new ARM platforms have been added, and changes have
been made that will make adding new platforms easier. And as always,
there are a number of performance, stability, and security
improvements under-the hood.
This file contains some quick-start instructions to install Xen on
your system. For more information see http:/www.xen.org/ and
http://wiki.xen.org/
Quick-Start Guide
=================
First, there are a number of prerequisites for building a Xen source
release. Make sure you have all the following installed, either by
visiting the project webpage or installing a pre-built package
provided by your OS distributor:
* GCC v4.1 or later
* GNU Make
* GNU Binutils
* Development install of zlib (e.g., zlib-dev)
* Development install of Python v2.3 or later (e.g., python-dev)
* Development install of curses (e.g., libncurses-dev)
* Development install of openssl (e.g., openssl-dev)
* Development install of x11 (e.g. xorg-x11-dev)
* Development install of uuid (e.g. uuid-dev)
* Development install of yajl (e.g. libyajl-dev)
* Development install of libaio (e.g. libaio-dev) version 0.3.107 or
greater.
* Development install of GLib v2.0 (e.g. libglib2.0-dev)
* Development install of Pixman (e.g. libpixman-1-dev)
* pkg-config
* bridge-utils package (/sbin/brctl)
* iproute package (/sbin/ip)
* udev
* GNU bison and GNU flex
* GNU gettext
* 16-bit x86 assembler, loader and compiler (dev86 rpm or bin86 & bcc debs)
* ACPI ASL compiler (iasl)
In addition to the above there are a number of optional build
prerequisites. Omitting these will cause the related features to be
disabled at compile time:
* Development install of Ocaml (e.g. ocaml-nox and
ocaml-findlib). Required to build ocaml components which
includes the alternative ocaml xenstored.
* cmake (if building vtpm stub domains)
* markdown
* figlet (for generating the traditional Xen start of day banner)
Second, you need to acquire a suitable kernel for use in domain 0. If
possible you should use a kernel provided by your OS distributor. If
no suitable kernel is available from your OS distributor then refer to
http://wiki.xen.org/wiki/XenDom0Kernels for suggestions for
suitable kernels to use.
If you are looking to compile a Dom0 kernel from source, please refer to
http://wiki.xen.org/wiki/XenParavirtOps.
[NB. Unless noted otherwise, all the following steps should be
performed with root privileges.]
1. Download and untar the source tarball file. This will be a
file named xen-unstable-src.tgz, or xen-$version-src.tgz.
You can also pull the current version from the mercurial
repository at http://xenbits.xen.org/
# tar xzf xen-unstable-src.tgz
Assuming you are using the unstable tree, this will
untar into xen-unstable. The rest of the instructions
use the unstable tree as an example, substitute the
version for unstable.
2. cd to xen-unstable (or whatever you sensibly rename it to).
3. For the very first build, or if you want to destroy build trees,
perform the following steps:
# ./configure
# make world
# make install
If you want, you can run ./configure --help to see the list of
options available options when building and installing Xen.
This will create and install onto the local machine. It will build
the xen binary (xen.gz), the tools and the documentation.
You can override the destination for make install by setting DESTDIR
to some value.
4. To rebuild an existing tree without modifying the config:
# make dist
This will build and install xen, tools, and docs into the local dist/
directory.
You can override the destination for make install by setting DISTDIR
to some value.
make install and make dist differ in that make install does the
right things for your local machine (installing the appropriate
version of udev scripts, for example), but make dist includes all
versions of those scripts, so that you can copy the dist directory
to another machine and install from that distribution.
Python Runtime Libraries
========================
Xend (the Xen daemon) has the following runtime dependencies:
* Python 2.3 or later.
In some distros, the XML-aspects to the standard library
(xml.dom.minidom etc) are broken out into a separate python-xml package.
This is also required.
In more recent versions of Debian and Ubuntu the XML-aspects are included
in the base python package however (python-xml has been removed
from Debian in squeeze and from Ubuntu in intrepid).
URL: http://www.python.org/
Debian: python
* For optional SSL support, pyOpenSSL:
URL: http://pyopenssl.sourceforge.net/
Debian: python-pyopenssl
* For optional PAM support, PyPAM:
URL: http://www.pangalactic.org/PyPAM/
Debian: python-pam
* For optional XenAPI support in XM, lxml:
URL: http://lxml.de/
Debian: python-lxml
YUM: python-lxml
Intel(R) Trusted Execution Technology Support
=============================================
Intel's technology for safer computing, Intel(R) Trusted Execution Technology
(Intel(R) TXT), defines platform-level enhancements that provide the building
blocks for creating trusted platforms. For more information, see
http://www.intel.com/technology/security/.
Intel(R) TXT support is provided by the Trusted Boot (tboot) module in
conjunction with minimal logic in the Xen hypervisor.
Tboot is an open source, pre- kernel/VMM module that uses Intel(R) TXT to
perform a measured and verified launch of an OS kernel/VMM.
The Trusted Boot module is available from
http://sourceforge.net/projects/tboot. This project hosts the code in a
mercurial repo at http://tboot.sourceforge.net/hg/tboot.hg and contains
tarballs of the source. Instructions in the tboot README describe how
to modify grub.conf to use tboot to launch Xen.
There are optional targets as part of Xen's top-level makefile that will
download and build tboot: install-tboot, build-tboot, dist-tboot, clean-tboot.
These will download the latest tar file from the SourceForge site using wget,
then build/install/dist according to Xen's settings.