Re: [RFC PATCH 0/6] ISAR SDK root filesystem

[Henning Schild <henning.schild@siemens.com>]

Am Wed, 13 Jun 2018 15:58:23 +0200
schrieb "Maxim Yu. Osipov" <mosipov@ilbers.de>:

> Hello everybody,
> 
> This series provides preliminary support of ISAR SDK root file system.
> 
> Motivation
> 
> Building applications for targets in ISAR takes a lot of time as they
> are built under QEMU. SDK providing crossbuild environment will help
> to solve this problem.
> 
> Approach
> 
> Create SDK root file system for host with installed cross-toolchain
> for target architecture and ability to install already prebuilt
> target binary artifacts. Developer chroots to sdk rootfs and develops
> applications for target platform.
> 
> Solution
> 
> User manually triggers creation of SDK root filesystem for his target
> platform by launching the task `do_isar_sdk` for target image, f.e.
> `bitbake -c do_isar_sdk
> multiconfig:${MACHINE}-${DISTRO}:isar-image-base`.
> 
> The resulting SDK rootfs is located under
> `tmp/work/${DITSRO}-${DISTRO_ARCH}/sdkchroot/rootfs`. SDK rootfs
> directory `/isar-apt` contains the copy of isar-apt repo with locally
> prebuilt target debian packages. One may chroot to SDK and install
> required target packages with the help of `apt-get install
> <package_name>:<DISTRO_ARCH>` command.
> 
> Limitation
> 
> Only Debian Stretch for SDK root filesystem is supported as only
> Stretch provides crossbuild environment by default. (Debian Jessie
> requires some additional preconfiguration steps see
> https://wiki.debian.org/CrossToolchains#Installation for details).

Are we ready for buster? Not many people care about the past, but let
us make sure this will work in the future.

> Example
> 
>  - Trigger creation of SDK root filesystem
> 
> 
> bitbake -c do_isar_sdk multiconfig:qemuarm-stretch:isar-image-base
> 
> 
>  - Mount the following directories in chroot by passing resulting
> rootfs as an argument to the script `mount_chroot.sh`:
> 
>
> $ cat mount_chroot.sh
> #!/bin/bash
> sudo mount /tmp     $1/tmp                 -o bind
> sudo mount proc     $1/proc    -t proc     -o nosuid,noexec,nodev
> sudo mount sysfs    $1/sys     -t sysfs    -o nosuid,noexec,nodev
> sudo mount devtmpfs $1/dev     -t devtmpfs -o mode=0755,nosuid
> sudo mount devpts   $1/dev/pts -t devpts   -o gid=5,mode=620
> sudo mount tmpfs    $1/dev/shm -t tmpfs    -o rw,seclabel,nosuid,nodev
> 
> $ ./mount_chroot.sh ./build/tmp/work/debian-stretch-armhf/sdkchroot/rootfs

Imagine this being copied over to a totally different Linux-distro or
into a docker container.

The "sudos" should not be in the script. So people can choose to not
use sudo at all or call the script with sudo.

Maybe adding a Dockerfile would be a good idea to understand more such
implications.

Henning
 
>  - chroot to isar SDK rootfs:
> 
> $ sudo chroot ./build/tmp/work/debian-stretch-armhf/sdkchroot/rootfs
> 
> 
>  - Check that cross toolchains are installed
> 
> 
> :~# dpkg -l | grep crossbuild-essential-armhf
> ii  crossbuild-essential-armhf           12.3
> all          Informational list of cross-build-essential packages
> 
> 
>  - Install needed prebuilt target packages.
> 
> 
> :~# apt-get install libhello-dev:armhf
> 
> 
>  - Check the contents of the installed target package
> 
> 
> :~# dpkg -L libhello-dev
> /.
> /usr
> /usr/include
> /usr/include/hello.h
> /usr/lib
> /usr/lib/arm-linux-gnueabihf
> /usr/lib/arm-linux-gnueabihf/libhello.a
> /usr/lib/arm-linux-gnueabihf/libhello.la
> /usr/share
> /usr/share/doc
> /usr/share/doc/libhello-dev
> /usr/share/doc/libhello-dev/changelog.gz
> /usr/share/doc/libhello-dev/copyright
> ~#
> 
> 
> Note:
> This code was not sync'ed with patchset 'Initial cross-compilation
> support' sent today by Alex. 
> 
> 
> Your comments/suggestions are welcome,
> 
> Kind regards,
> Maxim.
> 
> 
> Alexander Smirnov (1):
>   isar-debootstrap: split into host and target recipes
> 
> Maxim Yu. Osipov (5):
>   isar-bootstrap-helper: Add option --copyrepo to
>     setup_root_file_system()
>   sdkchroot: Added recipe-devel to create SDK root filesystem
>   meta/class/image: Add do_isar task to trigger SDK rootfs creation.
>   scripts: Add helper scripts to mount/umount chroot directory.
>   doc: Add description of ISAR SDK root filesystem creation
> 
>  doc/user_manual.md                                 | 90
> ++++++++++++++++++++++
> meta-isar/recipes-core/images/isar-image-base.bb   |  2 +-
> meta/classes/image.bbclass                         | 10 ++-
> meta/classes/isar-bootstrap-helper.bbclass         | 24
> +++++- .../isar-bootstrap/isar-bootstrap-host.bb          | 31
> ++++++++ .../isar-bootstrap/isar-bootstrap-target.bb        | 32
> ++++++++ .../{isar-bootstrap.bb => isar-bootstrap.inc}      | 24
> ------ meta/recipes-devtools/buildchroot/buildchroot.bb   |  4
> +- .../sdkchroot/files/configscript.sh                | 14 ++++
> meta/recipes-devtools/sdkchroot/sdkchroot.bb       | 59
> ++++++++++++++ scripts/mount_chroot.sh                            |
> 7 ++ scripts/umount_chroot.sh                           |  7 ++ 12
> files changed, 273 insertions(+), 31 deletions(-) create mode 100644
> meta/recipes-core/isar-bootstrap/isar-bootstrap-host.bb create mode
> 100644 meta/recipes-core/isar-bootstrap/isar-bootstrap-target.bb
> rename meta/recipes-core/isar-bootstrap/{isar-bootstrap.bb =>
> isar-bootstrap.inc} (89%) create mode 100644
> meta/recipes-devtools/sdkchroot/files/configscript.sh create mode
> 100644 meta/recipes-devtools/sdkchroot/sdkchroot.bb create mode
> 100755 scripts/mount_chroot.sh create mode 100755
> scripts/umount_chroot.sh
>