4 Jailhouse is a partitioning Hypervisor based on Linux. It is able to run
5 bare-metal applications or (adapted) operating systems besides Linux. For this
6 purpose it configures CPU and device virtualization features of the hardware
7 platform in a way that none of these domains, called "cells" here, can
8 interfere with each other in an unacceptable way.
10 Jailhouse is optimized for simplicity rather than feature richness. Unlike
11 full-featured Linux-based hypervisors like KVM or Xen, Jailhouse does not
12 support overcommitment of resources like CPUs, RAM or devices. It performs no
13 scheduling and only virtualizes those resources in software, that are essential
14 for a platform and cannot be partitioned in hardware.
16 Once Jailhouse is activated, it runs bare-metal, i.e. it takes full control
17 over the hardware and needs no external support. However, in contrast to other
18 bare-metal hypervisors, it is loaded and configured by a normal Linux system.
19 Its management interface is based on Linux infrastructure. So you boot Linux
20 first, then you enable Jailhouse and finally you split off parts of the
21 system's resources and assign them to additional cells.
24 WARNING: This is work in progress! Don't expect things to be complete in any
25 dimension. Use at your own risk. And keep the reset button in reach.
33 - https://github.com/siemens/jailhouse
37 - https://github.com/siemens/jailhouse.git
38 - git@github.com:siemens/jailhouse.git
42 - jailhouse-dev@googlegroups.com
45 - jailhouse-dev+subscribe@googlegroups.com
46 - https://groups.google.com/forum/#!forum/jailhouse-dev/join
49 - http://news.gmane.org/gmane.linux.jailhouse
51 Continuous integration:
53 - https://travis-ci.org/siemens/jailhouse
56 - ![](https://travis-ci.org/siemens/jailhouse.svg?branch=master) on master
57 - ![](https://travis-ci.org/siemens/jailhouse.svg?branch=next) on next
61 - https://scan.coverity.com/projects/4114
64 - ![](https://scan.coverity.com/projects/4114/badge.svg) on coverity_scan
66 See the [contribution documentation](CONTRIBUTING.md) for details
67 on how to write Jailhouse patches and propose them for upstream integration.
70 Requirements (preliminary)
71 --------------------------
77 - support for 64-bit and VMX, more precisely
78 - EPT (extended page tables)
79 - unrestricted guest mode
82 - Intel IOMMU (VT-d) with interrupt remapping support
83 (except when running inside QEMU)
87 - support for 64-bit and SVM (AMD-V), and also
88 - NPT (nested page tables); required
89 - Decode Assists; recommended
91 - AMD IOMMU (AMD-Vi) is unsupported now but will be required in future
93 - at least 2 logical CPUs
95 - x86-64 Linux kernel (tested against >= 3.14)
97 - VT-d IOMMU usage (DMAR) has to be disabled in the Linux kernel, e.g. via
98 the command line parameter:
102 - To exploit the faster x2APIC, interrupt remapping needs to be on in the
103 kernel (check for CONFIG_IRQ_REMAP)
109 - ARMv7 with virtualization extensions
111 - Appropriate boot loader support (typically U-Boot)
112 - Linux is started in HYP mode
113 - PSCI support for CPU offlining
115 - at least 2 logical CPUs
119 - Banana Pi (see also [below](#setup-on-banana-pi-arm-board))
121 - ARM Versatile Express with Cortex-A15 or A7 cores
122 (includes ARM Fast Model)
128 Simply run make, optionally specifying the target kernel directory:
130 make [KDIR=/path/to/kernel/objects]
132 Except for the hypervisor image `jailhouse*.bin` that has to be available in the
133 firmware search path (invoke `make firmware_install` for this), you can run
134 Jailhouse from the build directory. Alternatively, install everything on the
135 target machine by calling `make install` from the top-level directory.
141 Jailhouse requires one configuration file for the complete system and one for
142 each additional cell beside Linux. The configuration is currently being
143 defined manually by filling C structures. To study the structure, use
144 configs/qemu-vm.c for a system configuration and configs/apic-demo.c for a cell
145 configuration as reference. The build system will pick up every .c file from
146 the configs/ directory and generate a corresponding .cell file. .cell files can
147 then be passed to the jailhouse command line tool for enabling the hypervisor
148 and creating new cells.
151 Demonstration in QEMU/KVM
152 -------------------------
154 The included system configuration qemu-vm.c can be used to run Jailhouse in
155 QEMU/KVM virtual machine on x86 hosts (Intel and AMD are supported). Currently
156 it requires Linux 3.18 or newer on the host side (Intel is fine with 3.17).
157 QEMU is required in a recent version (2.1) as well if you want to use the
158 configuration file included in the source tree.
160 You also need a Linux guest image with a recent kernel (tested with >= 3.9) and
161 the ability to build a module for this kernel. Further steps depend on the type
162 of CPU you have on your system.
164 For Intel CPUs: Make sure the kvm-intel module was loaded with nested=1 to
165 enable nested VMX support. Start the virtual machine as follows:
167 qemu-system-x86_64 -machine q35 -m 1G -enable-kvm -smp 4 \
168 -cpu kvm64,-kvm_pv_eoi,-kvm_steal_time,-kvm_asyncpf,-kvmclock,+vmx,+x2apic \
169 -drive file=LinuxInstallation.img,id=disk,if=none \
170 -device ide-hd,drive=disk -serial stdio -serial vc \
171 -device intel-hda,addr=1b.0 -device hda-duplex
173 For AMD CPUs: Make sure the kvm-amd module was loaded with nested=1 to enable
174 nested SVM support. Start the virtual machine as follows:
176 qemu-system-x86_64 -machine q35 -m 1G -enable-kvm -smp 4 \
177 -cpu host,-kvm_pv_eoi,-kvm_steal_time,-kvm_asyncpf,-kvmclock,+svm,+x2apic \
178 -drive file=LinuxInstallation.img,id=disk,if=none \
179 -device ide-hd,drive=disk -serial stdio -serial vc \
180 -device intel-hda,addr=1b.0 -device hda-duplex
182 Inside the VM, make sure that jailhouse-*.bin, generated by the build process,
183 are available for firmware loading (typically /lib/firmware), see above for
186 The hypervisor requires a contiguous piece of RAM for itself and each
187 additional cell. This currently has to be pre-allocated during boot-up. So you
190 memmap=66M$0x3b000000
192 as parameter to the command line of the virtual machine's kernel. Reboot the
193 guest and load jailhouse.ko. Then enable Jailhouse like this:
195 jailhouse enable /path/to/qemu-vm.cell
197 Next you can create a cell with a demonstration application as follows:
199 jailhouse cell create /path/to/apic-demo.cell
200 jailhouse cell load apic-demo /path/to/apic-demo.bin -a 0xf0000
201 jailhouse cell start apic-demo
203 apic-demo.bin is left by the built process in the inmates/demos/x86 directory.
204 This application will program the APIC timer interrupt to fire at 10 Hz,
205 measuring the jitter against the PM timer and displaying the result on the
206 console. Given that this demonstration runs in a virtual machine, obviously
207 no decent latencies should be expected.
209 After creation, cells are addressed via the command line tool by providing
210 their names or their runtime-assigned IDs. You can obtain information about
211 active cells this way:
215 Cell destruction is performed by specifying the configuration file of the
216 desired cell. This command will destroy the apic-demo:
218 jailhouse cell destroy apic-demo
220 Note that the first destruction or shutdown request on the apic-demo cell will
221 fail. The reason is that this cell contains logic to demonstrate an ordered
222 shutdown as well as the ability of a cell to reject shutdown requests.
224 The apic-demo cell has another special property for demonstration purposes: As
225 long as it is running, no cell reconfigurations can be performed - the
226 apic-demo locks the hypervisor in this regard. In order to destroy another cell
227 or create an additional one, shut down the apic-demo first.
229 jailhouse cell shutdown apic-demo # call again if error is returned
231 To demonstrate the execution of a second, non-Linux cell, issue the following
234 jailhouse cell create /path/to/pci-demo.cell
235 jailhouse cell load pci-demo /path/to/pci-demo.bin -a 0xf0000
236 jailhouse cell start pci-demo
238 The pci-demo will use the second serial port provided by QEMU. You will find
239 its output in a virtual console of the QEMU window. The purpose of this demo is
240 to show basic PCI device configuration and MSI handling.
242 While cell configurations are locked, it is still possible, though, to reload
243 the content of existing cell (provided they accept their shutdown first). To
244 reload and restart the tiny-demo, issue the following commands:
246 jailhouse cell start apic-demo
247 jailhouse cell load pci-demo /path/to/pci-demo.bin -a 0xf0000
248 jailhouse cell start pci-demo
250 Finally, Jailhouse is can be stopped completely again:
252 jailhouse disable # call again on error due to running apic-demo
254 All non-Linux cells running at that point will be destroyed, and resources
255 will be returned to Linux.
258 Setup on Banana Pi ARM board
259 ----------------------------
261 The Banana Pi is a cheap Raspberry-Pi-like ARM board with an Allwinner A20 SoC
262 (dual-core Cortex-A7). It runs mainline Linux kernels and U-Boot and is
263 comparably well hackable. Further information can be found on
264 http://linux-sunxi.org.
266 For Jailhouse, a U-Boot (pre-)release more recent than v2015.04-rc1 is
267 required. Tested and know to work is git revision bd2a4888b1.
269 The Linux kernel version should be at least 3.19-rcX. The configuration used
270 for continuous integration builds can serve as reference, see
271 `ci/kernel-config-banana-pi`. The kernel has to be booted with the following
272 additional parameters, e.g. by adjusting the U-Boot environment accordingly:
274 mem=958M vmalloc=512M
276 The recommended cross-toolchain is available from Linaro, see
277 http://www.linaro.org/downloads.
279 Before building Jailhouse, copy the configuration header file
280 `ci/jailhouse-config-banana-pi.h` to `hypervisor/include/jailhouse/config.h`.
283 make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- \
284 KDIR=/path/to/arm-kernel/objects
286 Binaries can be installed directly to the target root file system if it is
289 make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- \
290 KDIR=/path/to/arm-kernel/objects DESTDIR=/mount-point install
292 Cell configurations and demo inmates will not be installed this way and have to
293 be transferred manually as needed. Make sure you have `configs/bananapi.cell`
294 and, as desired, the inmates configs (`configs/bananapi-*.cell`) and binaries
295 (`inmates/demos/arm/*.bin`) available on the target.
297 Jailhouse and inmates are started on ARM just like on x86. The only difference
298 is that inmates have to be loaded at offset 0. Just leave out the `-a`
299 parameter when invoking `jailhouse cell load`.