This document tries to describe the process of building Chromium OS and finally starting it as a virtual machine.
The main configuration of the laptop I am using:
- CPU: 4 cores, 2.7GHz
- Memory: 8G
- Network status: Watch Youtube stay at about 20Mbits/s.
My computer doesn't have much free space, this is my first big problem, I have to use an external hard drive. During the entire build process, the disk usage is close to 120G, so the hard drive partition you use to build Chromium OS should have 120G space.
And I think 8G memory is merely enough, it is better to have more memory, more memory can speed up the build process.
Although there is no special requirement for the hard disk in the official documentation, I think it is better to use an SSD - an SSD with more than 120G of free space. The external hard drive I have to use is not SSD, and the IO speed is about At 130 ~ 140 M / s, though the compilation process consumes CPU mainly, there will be a large number of temporary small files read and written during the compilation process, so SSD will have an advantage.
With my 4-core CPU, 8G memory and external HDD, it took 6 hours in the build_packages step, which is 4 times the 90 minutes in the official documentation, sad story.
There is also a humble suggestion, you'd better carry out the whole process in tmux or other similar tools to prevent closing the terminal window accidentally and interrupting an active command. If some commands run for a long time and there is no output, you can check if the related process is still active by using top, nethogs and other commands.
The first thing to say is that I am using zsh, so some environment changes are to modify $HOME/.zshrc. If you are using another shell such as bash, then you should change $HOME/.bashrc .
sudo apt-get install git-core gitk git-gui curl lvm2 thin-provisioning-tools \
Python-pkg-resources python-virtualenv python-oauth2client
In the $HOME/tools directory
git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
You can, of course, choose any other path you like. It is important to add the correct depot_tools path to the PATH environment variable by adding this line to the $HOME/.zshrc file:
export PATH=$PATH:$HOME/tools/depot_tools
After source $HOME/.zshrc reloads the $HOME/.zshrc file, the changes to the environment variables take effect.
Add the following to the /etc/sudoers.d/relax_requirements file.
Defaults !tty_tickets
Defaults timestamp_timeout=400
The effect of this is: Execute a sudo command in a terminal, after entering the password, execute a sudo command in the newly opened terminal, you would not need to enter the password again, until 400 minutes later.
The official documentation says a 180 minutes timeout, but in fact, the build process in my laptop is far more than 180 minutes, so I suggest setting this time longer if you have a normal computer.
- Execute
uname -mto verify that the system CPU architecture isX86_64. - Execute
umaskto confirm that the default permissions are ok. The result should be022or002to ensure that the files and directories are readable externally.
You probably already have this step already done.
git config --global user.email "you@example.com"
git config --global user.name "Your Name"
Since I am using an external hard drive, I created the chromiumos directory in the partition of the external hard drive and made a soft link to it in the HOME directory.
mkdir -p /media/noodles/Tatooine/playground/chromiumos
ln -s /media/noodles/Tatooine/playground/chromiumos ${HOME}/chromiumos
Before pulling the source code, you need to follow [http://www.chromium.org/chromium-os/developer-guide/gerrit-guide] (http://www.chromium.org/chromium-os/developer-guide/ Gerrit-guide) set Gerrit authentication, you will get a script from that web page, append it to .zshrc, then source .zshrc. Then execute
git ls-remote https://chromium.googlesource.com/a/chromiumos/manifest.git
If there is no authentication process, the git related content is directly output, indicating that the setting is successful. The source code can be obtained smoothly later.
Next, cd ${HOME}/chromiumos, entering the chromiumos directory.
repo init -u https://chromium.googlesource.com/chromiumos/manifest.git --repo-url https://chromium.googlesource.com/external/repo.git
In the end, there will be a small question for you
Enable color display in this user account (y/N)?
I chose Y.
Then execute
repo sync -j4
It gets the source code, -j4 means 4 concurrent tasks to synchronize, and synchronize 4 warehouses at the same time. The average speed was about 38Mbits/s, it started at 08:05 and ended at 10:20, which was more time consuming than I expected.
There is nothing you can do in the two hours of synchronizing the source code. If you want to build Chromium OS to use Google's API, provide login, translation and other features, then during this period, you can go
http://www.chromium.org/developers/how-tos/api-keys take a look at the page and follow the instructions. You will get an API KEY, client ID and client Secret, save them in the $HOME/.googleapikeys file.
google_api_key = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
google_default_client_id = "yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy"
google_default_client_secret = "zzzzzzzzzzzzzzzzzzzzzzzz"
After the code synchronization is complete. You should still be in the ${HOME}/chromiumos directory now. Execute
cros_sdk
This command pulls a chroot environment from Google and then enters the chroot environment. It takes me about ten minutes to complete and enter the chroot environment. Unless otherwise stated, the commands following are performed in this chroot environment.
First, specify which platform you want to build for, execute export BOARD=amd64-generic, and use the BOARD environment variable as a parameter when you actually perform the real build configuration and compilation process.
Then execute ./setup_board --board=${BOARD} to prepare for the compilation. This step will download some content, which takes from a few minutes to twenty minutes.
Chromium OS will provide a shared account called chronos, which can be used to log in to the system from the command line. Before executing ./build_packages --board=${BOARD} to compile, you may want to set a password for this shared account, execute ./set_shared_user_password.sh to set. If you build a image of test mode, the password set here will be ignored, and the password for test mode is test0000.
Then execute ./build_packages --board=${BOARD} to start compiling all the packages. I think that this step takes 80% ~ 90% of the time spent on the whole process. The only comfort is that you can see the progress. In the output of this process, you can see something like this:
Pending 481/648, Building 4/286, [Time 15:36:15 | Elapsed 127m16.6s | Load 10.86 11.22 10.68]
In this example, 481 in Pending 481/648 is the number of packages to be compiled, and 4' in Building 4/286is the number of packages being compiled. You can see how long this step has taken byElapsed 127m16.6s`.
Organize the complete step commands from preparation to build packages:
export BOARD=amd64-generic
./setup_board --board=${BOARD}
./set_shared_user_password.sh ## optional
./build_packages --board=${BOARD}
The BOARD I set at first is x86-generic, and I encountered an error in the build_packages step, specifically when I reached this step:
INFO : Checking package dependencies are correct: virtual/target-os virtual/target-os-dev virtual/target-os-factory virtual/target-os-factory-shim virtual/target-os-test chromeos-base/autotest-all
The following error occurred:
!!! The ebuild selected to satisfy "chromeos-base/chromeos-chrome" for /build/x86-generic/ has unmet requirements.
- chromeos-base / chromeos-chrome-71.0.3544.0_rc-r1 :: chromiumos USE = "accessibility autotest build_tests buildcheck cfi chrome_debug chrome_remoting cups debug_fission evdev_gestures fonts gold highdpi libcxx nacl opengles runhooks smbprovider thinlto v4l2_codec vaapi xkbcommon -afdo_use -app_shell -asan ( -authpolicy) -build_native_assistant -chrome_debug_tests -chrome_internal -chrome_media -clang -clang_tidy -component_build -goma -hardfp -internal_gles_conform -jumbo -lld -mojo (-oobe_config -opengl -v4lplugin -verbose -vtable_verify "OZONE_PLATFORM =" default_gbm gbm -neon) - Caca -cast -default_caca -default_cast -default_egltest -default_test -egltest -test" OZONE_PLATFORM_DEFAULT="gbm -caca -cast -egltest -test"
The following REQUIRED_USE flag constraints are unsatisfied:
Libcxx? ( clang ) thinlto? ( clang )
The above constraints are a subset of the following complete expression:
asan? (clang) at-most-one-of (gold lld) cfi? (thinlto) clang_tidy? (clang) libcxx? (clang) thinlto? (clang any-of (gold lld)) afdo_use? (clang) exactly- One-of (Ozone_platform_default_gbm ozone_platform_default_cast ozone_platform_default_test ozone_platform_default_egltest ozone_platform_default_caca )
(dependency required by "chromeos-base/autotest-chrome-0.0.1-r7313::chromiumos" [ebuild])
(dependency required by "chromeos-base/autotest-all-0.0.1-r46::chromiumos[-chromeless_tests,-chromeless_tty]" [ebuild])
(dependency required by "chromeos-base/autotest-all" [argument])
ERROR : emerge detected broken ebuilds. See error message above.
After trying to execute eclean -d packages, re-execute ./build_packages --board=${BOARD} , it still output the same error.
Then I continued to try, go back to the previous step, execute ./setup_board --board=${BOARD} --force to force the rebuild of board root, then re-execute the build_packages command, the problem remains.
Finally, I had to compile with amd64-generic as the parameter.
More information: https://groups.google.com/a/chromium.org/forum/#!topic/chromium-os-discuss/0wJ0v9XBIu8
./build_image --board=${BOARD} --noenable_rootfs_verification test
The
--noenable_rootfs_verificationturns off verified boot allowing you to freely modify the root file system. The system is less secure using this flag, however, for rapid development you may want to set this flag. If you would like a more secure, locked-down version of Chromium OS, then simply remove the--noenable_rootfs_verificationflag.
There is a progress display similar to when the build_package command is executed.
Pending 56/86, Building 4/57, [Time 19:48:34 | Elapsed 0m34.6s | Load 4.5 5.67 7.74]
Final time consuming
INFO : Elapsed time (build_image): 22m9s
This section at the end clearly describes how to use this image file.
INFO : Test image created as chromiumos_test_image.bin
INFO : To copy the image to a USB key, use:
INFO : cros flash usb:// ../build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_test_image.bin
INFO : To convert it to a VM image, use:
INFO : ./image_to_vm.sh --from=../build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1 --board=amd64-generic --test
Execute the command according to the last output of the previous step
./image_to_vm.sh --from=../build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1 --board=amd64-generic --test
During the conversion process, I checked the hard drive space, the current disk usage 116G.
After the conversion is completed, there is such a piece of content output:
Created image at /mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1
You can start the image with:
Cros_vm --start --image-path /mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_qemu_image.bin
Follow the instructions in the previous step, execute cros_vm --start --image-path /mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_qemu_image.bin, there's an error:
IOError: [Errno 13] Permission denied: '/tmp/cros_vm_9222/kvm.monitor.serial'
At first I thought it was a problem with the chroot environment (because the time to compile the package and build the image far exceeded the sudo timeout set by me for 180 minutes), so I tried to execute cros_sdk --unmount out of the chroot environment, then execute cros_sdk again, enter the chroot environment, execute cros_vm, result of the same permissions issue.
Then I modified the /tmp/cros_vm_9222 directory in the chroot environment to 777 (very very practice), but the cros_vm still reported the same error and the directory permissions changed to 775. It indicated that cros_vm will modify the permissions of this directory during execution.
/tmp/cros_vm_9222 Directory permissions are 775, according to cros_vm error stack information, in the /mnt/host/source/chromite directory, I grep 775 found /mnt/host/source/chromite/lib/osutils.py file, modified the default parameters of the following two functions, changed mode=0o775 to mode=0o777.
Def SafeMakedirsNonRoot(path, mode=0o777, user=None)
Def SafeMakedirs(path, mode=0o777, sudo=False, user='root')
OK, I can continue now, but the permissions of 777 are really ugly, so I recovered /mnt/host/source/chromite/lib/osutils.py and use sudo to execute cros_vm.
sudo /mnt/host/source/chromite/bin/cros_vm --start --image-path /mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_qemu_image.bin
After the problem of the previous step was solved, it still failed to start up and there were new errors.
21:09:41: INFO: RunCommand: sudo -- /mnt/host/source/chroot/usr/bin/qemu-system-x86_64 -m 8G -smp 8 -vga virtio -daemonize -usbdevice tablet -pidfile /tmp/ Cros_vm_9222/kvm.pid -chardev 'pipe,id=control_pipe,path=/tmp/cros_vm_9222/kvm.monitor' -serial file:/tmp/cros_vm_9222/kvm.monitor.serial -mon 'chardev=control_pipe' -cpu SandyBridge, -invpcid,-tsc-deadline,check -device 'virtio-net,netdev=eth0' -netdev 'user,id=eth0,net=10.0.2.0/27,hostfwd=tcp:127.0.0.1:9222-:22' -drive 'file=/mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_qemu_image.bin,index=0,media=disk,cache=unsafe,format=raw' -enable-kvm
Qemu-system-x86_64: cannot set up guest memory 'pc.ram': Cannot allocate memory
Looking at this content, it should be specifying too much memory, and the system cannot allocate. According to the stack information of the error, I found the relevant directory, grep this keyword 8G, modify the line in /mnt/host/source/chromite/scripts/cros_vm.py, change 8G to 4G.
parser.add_argument('--qemu-m', type=str, default='4G',
Help='Memory argument that will be passed to qemu.')
It's OK and the virtual machine is up.
21:12:56: INFO: RunCommand: sudo -- /mnt/host/source/chroot/usr/bin/qemu-system-x86_64 -m 4G -smp 8 -vga virtio -daemonize -usbdevice tablet -pidfile /tmp/ Cros_vm_9222/kvm.pid -chardev 'pipe,id=control_pipe,path=/tmp/cros_vm_9222/kvm.monitor' -serial file:/tmp/cros_vm_9222/kvm.monitor.serial -mon 'chardev=control_pipe' -cpu SandyBridge, -invpcid,-tsc-deadline,check -device 'virtio-net,netdev=eth0' -netdev 'user,id=eth0,net=10.0.2.0/27,hostfwd=tcp:127.0.0.1:9222-:22' -drive 'file=/mnt/host/source/src/build/images/amd64-generic/R71-11065.0.2018_09_15_1932-a1/chromiumos_qemu_image.bin,index=0,media=disk,cache=unsafe,format=raw' -enable-kvm
VNC server running on '127.0.0.1;5900'
As you can see from the above information, the virtual machine's ssh 22 port is mapped to the local 127.0.0.1:9222 port.
ssh root@localhost -p 9222
Enter the system with the password test0000. You can also use the chronos account mentioned above to enter the system.
localhost ~ # uname -r
4.4.155-15233-g439d815e28b7
Localhost ~ # cat /etc/lsb-release
CHROMEOS_RELEASE_BOARD=amd64-generic
CHROMEOS_DEVSERVER=http://Noodles-ThinkPad-T470:8080
GOOGLE_RELEASE=11065.0.2018_09_15_1932
CHROMEOS_RELEASE_BUILD_NUMBER=11065
CHROMEOS_RELEASE_BRANCH_NUMBER=0
CHROMEOS_RELEASE_CHROME_MILESTONE=71
CHROMEOS_RELEASE_PATCH_NUMBER=2018_09_15_1932
CHROMEOS_RELEASE_TRACK=testimage-channel
CHROMEOS_RELEASE_DESCRIPTION=11065.0.2018_09_15_1932 (Test Build - noodles) developer-build amd64-generic
CHROMEOS_RELEASE_NAME=Chromium OS
CHROMEOS_RELEASE_BUILD_TYPE=Test Build - noodles
CHROMEOS_RELEASE_VERSION=11065.0.2018_09_15_1932
CHROMEOS_AUSERVER=http://Noodles-ThinkPad-T470:8080/update
Using the VNC client connect to 127.0.0.1:5900, the connection was successful, but no content was displayed, just a black window.