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
52 Requirements (preliminary)
53 --------------------------
59 - support for 64-bit and VMX, more precisely
60 - EPT (extended page tables)
61 - unrestricted guest mode
64 - Intel IOMMU (VT-d) with interrupt remapping support
65 (except when running inside QEMU)
69 - support for 64-bit and SVM (AMD-V), and also
70 - NPT (nested page tables); required
71 - Decode Assists; recommended
73 - AMD IOMMU (AMD-Vi) is unsupported now but will be required in future
75 - at least 2 logical CPUs
77 - x86-64 Linux kernel (tested against >= 3.14)
78 - VT-d IOMMU usage (DMAR) has to be disabled in the Linux kernel, e.g. via
79 the command line parameter:
83 - To exploit the faster x2APIC, interrupt remapping needs to be on in the
84 kernel (check for CONFIG_IRQ_REMAP)
90 Simply run make, optionally specifying the target kernel directory:
92 make [KDIR=/path/to/kernel/objects]
94 Except for the hypervisor image `jailhouse*.bin` that has to be available in the
95 firmware search path (invoke `make firmware_install` for this), you can run
96 Jailhouse from the build directory. Alternatively, install everything on the
97 target machine by calling `make install` from the top-level directory.
103 Jailhouse requires one configuration file for the complete system and one for
104 each additional cell beside Linux. The configuration is currently being
105 defined manually by filling C structures. To study the structure, use
106 configs/qemu-vm.c for a system configuration and configs/apic-demo.c for a cell
107 configuration as reference. The build system will pick up every .c file from
108 the configs/ directory and generate a corresponding .cell file. .cell files can
109 then be passed to the jailhouse command line tool for enabling the hypervisor
110 and creating new cells.
113 Demonstration in QEMU/KVM
114 -------------------------
116 The included system configuration qemu-vm.c can be used to run Jailhouse in
117 QEMU/KVM virtual machine on x86 hosts (Intel and AMD are supported). Currently
118 it requires Linux 3.18 or newer on the host side (Intel is fine with 3.17).
119 QEMU is required in a recent version (2.1) as well if you want to use the
120 configuration file included in the source tree.
122 You also need a Linux guest image with a recent kernel (tested with >= 3.9) and
123 the ability to build a module for this kernel. Further steps depend on the type
124 of CPU you have on your system.
126 For Intel CPUs: Make sure the kvm-intel module was loaded with nested=1 to
127 enable nested VMX support. Start the virtual machine as follows:
129 qemu-system-x86_64 -machine q35 -m 1G -enable-kvm -smp 4 \
130 -cpu kvm64,-kvm_pv_eoi,-kvm_steal_time,-kvm_asyncpf,-kvmclock,+vmx,+x2apic \
131 -drive file=LinuxInstallation.img,id=disk,if=none \
132 -device ide-hd,drive=disk -serial stdio -serial vc \
133 -device intel-hda,addr=1b.0 -device hda-duplex
135 For AMD CPUs: Make sure the kvm-amd module was loaded with nested=1 to enable
136 nested SVM support. Start the virtual machine as follows:
138 qemu-system-x86_64 -machine q35 -m 1G -enable-kvm -smp 4 \
139 -cpu host,-kvm_pv_eoi,-kvm_steal_time,-kvm_asyncpf,-kvmclock,+svm,+x2apic \
140 -drive file=LinuxInstallation.img,id=disk,if=none \
141 -device ide-hd,drive=disk -serial stdio -serial vc \
142 -device intel-hda,addr=1b.0 -device hda-duplex
144 Inside the VM, make sure that jailhouse-*.bin, generated by the build process,
145 are available for firmware loading (typically /lib/firmware), see above for
148 The hypervisor requires a contiguous piece of RAM for itself and each
149 additional cell. This currently has to be pre-allocated during boot-up. So you
152 memmap=66M$0x3b000000
154 as parameter to the command line of the virtual machine's kernel. Reboot the
155 guest and load jailhouse.ko. Then enable Jailhouse like this:
157 jailhouse enable /path/to/qemu-vm.cell
159 Next you can create a cell with a demonstration application as follows:
161 jailhouse cell create /path/to/apic-demo.cell
162 jailhouse cell load apic-demo /path/to/apic-demo.bin -a 0xf0000
163 jailhouse cell start apic-demo
165 apic-demo.bin is left by the built process in the inmates/demos/x86 directory.
166 This application will program the APIC timer interrupt to fire at 10 Hz,
167 measuring the jitter against the PM timer and displaying the result on the
168 console. Given that this demonstration runs in a virtual machine, obviously
169 no decent latencies should be expected.
171 After creation, cells are addressed via the command line tool by providing
172 their names or their runtime-assigned IDs. You can obtain information about
173 active cells this way:
177 Cell destruction is performed by specifying the configuration file of the
178 desired cell. This command will destroy the apic-demo:
180 jailhouse cell destroy apic-demo
182 Note that the first destruction or shutdown request on the apic-demo cell will
183 fail. The reason is that this cell contains logic to demonstrate an ordered
184 shutdown as well as the ability of a cell to reject shutdown requests.
186 The apic-demo cell has another special property for demonstration purposes: As
187 long as it is running, no cell reconfigurations can be performed - the
188 apic-demo locks the hypervisor in this regard. In order to destroy another cell
189 or create an additional one, shut down the apic-demo first.
191 jailhouse cell shutdown apic-demo # call again if error is returned
193 To demonstrate the execution of a second, non-Linux cell, issue the following
196 jailhouse cell create /path/to/pci-demo.cell
197 jailhouse cell load pci-demo /path/to/pci-demo.bin -a 0xf0000
198 jailhouse cell start pci-demo
200 The pci-demo will use the second serial port provided by QEMU. You will find
201 its output in a virtual console of the QEMU window. The purpose of this demo is
202 to show basic PCI device configuration and MSI handling.
204 While cell configurations are locked, it is still possible, though, to reload
205 the content of existing cell (provided they accept their shutdown first). To
206 reload and restart the tiny-demo, issue the following commands:
208 jailhouse cell start apic-demo
209 jailhouse cell load pci-demo /path/to/pci-demo.bin -a 0xf0000
210 jailhouse cell start pci-demo
212 Finally, Jailhouse is can be stopped completely again:
214 jailhouse disable # call again on error due to running apic-demo
216 All non-Linux cells running at that point will be destroyed, and resources
217 will be returned to Linux.
220 Setup on Banana Pi ARM board
221 ----------------------------
223 The Banana Pi is a cheap Raspberry-Pi-like ARM board with an Allwinner A20 SoC
224 (dual-core Cortex-A7). It runs mainline Linux kernels and U-Boot and is
225 comparably well hackable. Further information can be found on
226 http://linux-sunxi.org.
228 For Jailhouse, U-Boot currently requires a few additional patches that can be
229 retrieved from https://github.com/siemens/u-boot/commits/sunxi.
231 The Linux kernel version should be at least 3.19-rcX. The configuration used
232 for continuous integration builds can serve as reference, see
233 `ci/kernel-config-banana-pi`. The kernel has to be booted with the following
234 additional parameters, e.g. by adjusting the U-Boot environment accordingly:
236 mem=958M vmalloc=512M
238 The recommended cross-toolchain is available from Linaro, see
239 http://www.linaro.org/downloads.
241 Before building Jailhouse, copy the configuration header file
242 `ci/jailhouse-config-banana-pi.h` to `hypervisor/include/jailhouse/config.h`.
245 make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- \
246 KDIR=/path/to/arm-kernel/objects
248 Binaries can be installed directly to the target root file system if it is
251 make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- \
252 KDIR=/path/to/arm-kernel/objects DESTDIR=/mount-point install
254 Cell configurations and demo inmates will not be installed this way and have to
255 be transferred manually as needed. Make sure you have `configs/bananapi.cell`
256 and, as desired, the inmates configs (`configs/bananapi-*.cell`) and binaries
257 (`inmates/demos/arm/*.bin`) available on the target.
259 Jailhouse and inmates are started on ARM just like on x86. The only difference
260 is that inmates have to be loaded at offset 0. Just leave out the `-a`
261 parameter when invoking `jailhouse cell load`.