Accessing advanced BIOS menu

Preparation

First using a needle or a toothpick click a button on the right side of the laptop (indicated by a bent arrow), this will start the machine up in BIOS selection menu where you choose the BIOS setup option.

Then, in the BIOS menu disable option to check laptop charge level while it is shut down. If not disabled it will interfere with key combination that has to be pressed while laptop is shut down. This can be turned back after the advanced BIOS menu is enabled.

After that "Exit saving changes" and shutdown.

Keys

I thought it was a joke at first but it really is true that a special combination of keys has to be pressed depending on the laptop model (while it is shut down).

For my laptop it is as follows:

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F4 4 r f v
F5 5 t g b
F6 6 y h n

References

• Lenovo product page: https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/ideapad-s-series-netbooks/s340-15api/81nc
• https://www.reddit.com/r/Fedora/comments/r2m6my/comment/hm9dddn/?utm_source=share&utm_medium=web2x&context=3

Template

File: /etc/systemd/system/APP.service

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[Unit]
Description=Run APP application

[Service]
Type=simple
ExecStart=/usr/bin/LANG APP_DIR/APP APP_ARGS
Restart=on-failure
User=root
WorkingDirectory=APP_DIR

[Install]
WantedBy=multi-user.target

Also, the application might need to reference a PID file, let systemD know abut it via PIDFile.

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PIDFile=/tmp/APP.pid

Example

File: /etc/systemd/system/julia_dash_app.service

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[Unit]
Description=Run Julia Dash application

[Service]
Type=simple
ExecStart=/usr/bin/julia /root/julia_dash_app/main.jl
Restart=on-failure
User=root
WorkingDirectory=/root/julia_dash_app

[Install]
WantedBy=multi-user.target

Potential benefits

Running tests

• test BEFORE (src_test) and AFTER (pkg_postinst) installation
• test if and how services break if they are not reloaded
• test buildsystem configuration
• sandbox enforces strict and consistent build rules
• benchmarking with different compilation flags and libraries versions/releases

Configuration matrix

We can test across Cartesian product of different configuration settings, like:

• USE flags
• MAKEOPTS
• CFLAGS, CXXFLAGS, CPPFLAGS, LDFAGS, RUSTFLAGS, etc.
• arches (cross-compilation or run in qemu)
• static linking
• supported releases & versions of libraries (eg. glibc & musl)

Also, we could create diffs of installed files across different merges.

Reproducibility

• mini overlay with ::gentoo or any other (eg. company's own) as master
• record VCS (eg. git) hash of the dependent overlays

Binaries

• grab dependencies from binhosts
• distribute built binaries (maybe upload to a company's own artifacts server)
• make AppImages

Getting there

How do we run this?

Do we want to write a proper tool, which we probably do or do we just run Portage + shells scripts?

Do we want to run under root, user, in eprefix, maybe all in docker?

Configuration files

The .portci directory contains the configuration.

Bug 799626

Link: bugs.gentoo.org/799626

Instead of using Ansible, Python, Yaml or Scheme we might use something similar to this for simple configuration, or if gets merged to upstream Portage the better.

Worth mentioning is the idea from Michał Górny who proposes to configure portage with toml files, like the example given in the bug report.

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[package.unmask]
~virtual/libcrypt-2

[package.use.mask]
sys-libs/libxcrypt -system -split-usr

[package.use.force]
sys-libs/glibc -crypt

Also, package.x + Toml == a match made in heaven, it looks very nice!

Switching from a git repository hosting

For nearly 2 years I have been synchronizing settings between my Gentoo machines via a git repository that is installed system-wide via portage itself.

This actually gets a little tiresome and slow as the package that installs the configuration has to be re-installed each time we want to update the settings.

So I thought it could be cool if I can just push files around between my machines with one command. Now: we can use rsync or scp but /etc/portage is owned by root so we either have to change the permissions to a user we use to ssh or a group that user is in.

Portage users

First change portage permissions of /etc/portage, now all users in the portage group will be able to modify the configuration

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chown -R root:portage /etc/portage
chmod -R g+w /etc/portage

Synchronizing

We can do a rsync from different machine with:

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rsync -r /etc/portage REMOTEHOST:/etc --exclude=".git" --exclude="make.profile" --copy-unsafe-links

Reminder that this can also be done as a cron job!

Portage snapshots with git

Probably the best thing I got out of genlica is that I engineered a script to automatically do a git commit of the changes to the portage configuration.

Emerge git

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emerge --noreplace --verbose dev-vcs/git

Copy the file that does the snapshots

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mkdir -p /etc/portage/postsync.d
curl -o /etc/portage/postsync.d/99-degitmerge.sh "https://gitlab.com/xgqt/genlica/-/raw/master/portage/postsync.d/99-degitmerge.sh"

Make gallery-dl work like youtube-dl

A configuration file to download everything into current directory, like yotube-dl does.

File: ~/.config/gallery-dl/config.json

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{
  "directory": [],
  "base-directory": "./"
}