It appears that rngd is not needed as of linux-5.6 and later[1]
and should not be installed by default since the purpose of rngd
is to provide additional trusted sources of entropy.
We did some testing on real hardware, the result seems to support that
we no longer need rngd by default on kernel v5.6 and later.
Testing result as below:
1. observing the crng init stage.
the "random: crng init done" always available before fs being mounted.
2. generating random number without rngd.
testing command: dd if=/dev/random of=/dev/null status=progress
on Marvell CN96xx RDB board, speed almost 20.4 MB/s without block
on NXP i.mx6q board, speed almost 31.9 MB/s without block
on qemu x86-64, speed almost 2.6MB/s without block
3. using rngtest command without rngd
testing command: rngtest -c 1000 </dev/random
on Marvell CN96xx RDB board:
rngtest: input channel speed: (min=4.340; avg=135.364; max=146.719)Mibits/s
rngtest: FIPS tests speed: (min=8.197; avg=69.020; max=72.800)Mibits/s
rngtest: Program run time: 418771 microseconds
on NXP i.mx6q board:
rngtest: input channel speed: (min=96.820; avg=326.769; max=340.598)Mibits/s
rngtest: FIPS tests speed: (min=15.090; avg=37.543; max=40.324)Mibits/s
rngtest: Program run time: 570229 microseconds
on qemu x86-64:
rngtest: input channel speed: (min=37.769; avg=101.136; max=136.239)Mibits/s
rngtest: FIPS tests speed: (min=10.288; avg=30.682; max=40.155)Mibits/s
rngtest: Program run time: 836800 microseconds
4. observing sshd service.
using "systemctl disable rng-tools" disable service and reboot system.
system boot up normal, sshd service also start in normal time without
block.
Reference:
[1] 30c08efec8
(From OE-Core rev: 2ed579aa28194cf671e5d4f4c61dc38d05de4b0c)
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
(cherry picked from commit 868dfb46d96a27ec9041cb902fb769330277257d)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a pre-packaged build system and development environment which is used as a development and validation tool by the Yocto Project. It features support for building customised embedded style device images and custom containers. There are reference demo images ranging from X11/GTK+ to Weston, commandline and more. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK suitable for IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of BSP layers which extend the systems capabilities in a modular way. Many layers are available and can be found through the layer index.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation, the 'meta-yocto' layer which has configuration and hardware support components. These components are all part of the Yocto Project and OpenEmbedded ecosystems.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at https://docs.yoctoproject.org/
OpenEmbedded is the build architecture used by Poky and the Yocto project. For information about OpenEmbedded, see the OpenEmbedded website.
Contribution Guidelines
The project works using a mailing list patch submission process. Patches should be sent to the mailing list for the repository the components originate from (see below). Throughout the Yocto Project, the README files in the component in question should detail where to send patches, who the maintainers are and where bugs should be reported.
A guide to submitting patches to OpenEmbedded is available at:
https://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded
There is good documentation on how to write/format patches at:
https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines
Where to Send Patches
As Poky is an integration repository (built using a tool called combo-layer), patches against the various components should be sent to their respective upstreams:
OpenEmbedded-Core (files in meta/, meta-selftest/, meta-skeleton/, scripts/):
- Git repository: https://git.openembedded.org/openembedded-core/
- Mailing list: openembedded-core@lists.openembedded.org
BitBake (files in bitbake/):
- Git repository: https://git.openembedded.org/bitbake/
- Mailing list: bitbake-devel@lists.openembedded.org
Documentation (files in documentation/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
- Mailing list: docs@lists.yoctoproject.org
meta-yocto (files in meta-poky/, meta-yocto-bsp/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto
- Mailing list: poky@lists.yoctoproject.org
If in doubt, check the openembedded-core git repository for the content you intend to modify as most files are from there unless clearly one of the above categories. Before sending, be sure the patches apply cleanly to the current git repository branch in question.