Using Fedora 23 on a MacBook Pro

For the past few months, I’ve been using Fedora as my main OS on my laptop, a 2014-ish MacBook Pro. OSX is not bad, but it does not have native support for things like Docker.

I still have my OSX partition setup in case I need something that I can’t do on Linux (like updating the firmware or enabling/disabling the startup sound).

These are some of notes I’ve collected along the way:

Writing the ISO to a USB stick

If you are installing Fedora on a MBP, you are probably running OSX initially. How do you write the ISO image into a USB stick and make it bootable?

I’ve found that Ubuntu’s guide on the topic is the easiest one to follow and works with the Fedora image too.

Here’s a quick summary:

hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/fedora.iso
diskutil unmountDisk /dev/diskN
sudo dd if=~/path/to/target.img of=/dev/diskN bs=1m
diskutil eject /dev/diskN

See below on how to boot into the live image.

Dual-booting is possible without any additional software

Some guides for installing Linux on MacBooks point you to installing UEFI software like rEFInd. I would consider this an optional step since the laptop’s firmware has an OS selection screen built-in.

For both, booting the live image and picking which OS to boot, all you have to do is hold down the alt key while the laptop is booting and pick what you want to boot. If you formatted the USB stick correctly, Fedora should be an option.

TIP: You can setup a firmware password to protect the OS selection screen (just like it would on a PC).

Going online (wireless-ly)

Like on other laptops on Linux, the wireless card needs some drivers before you can use it.

On Fedora, the MacBook card’s driver is available under the akmod-wl package. However, you will first need to enable the RPM fusion repositories (both free and non-free).

The easiest way to do this is to use a Thunderbolt Ethernet adapter or to tether your phone. Otherwise, you will porbably need to copy a couple of RPMs.

TIP: On some cases, the kernel-headers package will have a different version from the current kernel in your system. This will prevent akmod from compiling the module. You should run dnf upgrade if that happens.

After restarting, the module should be compiled and you should be able to connect to an access point.

Turning off that red light

After booting Fedora (or any other Linux distribution), you will most likely notice that there is an odd red light coming out your laptop’s headphone jack. This is normal. The headphone jack on MacBooks has a S/PDIF port built-in.

The reason why the light is on while using Linux is that, by default, Linux does not enable power saving mode on the audio card. However, its very easy to enable it:

# As root:
echo 1 > /sys/module/snd_hda_intel/parameters/power_save

Additional power saving toggles can be found using powertop.

Go to sleep

For some reason, something keeps waking up the laptop after you press the power button or close the lid. Having you laptop turn on inside your bag is not fun!

The workaround seems to disable a couple of wakeup triggers:

# As root:
echo LID0 > /proc/acpi/wakeup
echo XHC1 > /proc/acpi/wakeup

The side effect being that your laptop won’t turn on automatically when you open the lid, however, you can now safely put it in your bag.

The webcam

The only piece of hardware that you’ll find that does not work on Linux is the webcam. This is due to the fact that the drivers for it are not open source.

There is, however, an ongoing effort to build/reverse-engineer a driver for Linux.

As a systemd unit

I wrote a small unit file that will fix the red light and wake up issues at boot time:

[Unit]
Description=Improve MacBook setup

[Service]
Type=oneshot
ExecStart=/bin/bash -c "echo 1 > /sys/module/snd_hda_intel/parameters/power_save && echo LID0 > /proc/acpi/wakeup && echo XHC1 > /proc/acpi/wakeup"

[Install]
WantedBy=multi-user.target

Save this file as /etc/systemd/system/mbp.service and run systemctl daemon-reload && systemctl enable mbp to load the unit on every boot.