332
votes
Accepted
What is rpikernelhack?
"rpikernelhack" is a fake package name and a directory name used as part of a hack (in the sense of a dirty but expedient solution to a problem) to work around the fact that the Raspberry Pi ...
- 6,546
53
votes
What is rpikernelhack?
It's just the directory name given by the developers who have created a Raspberry Pi specific set of patches to the Linux kernel.
It is a fix by the Raspbian developers to fix a FAT file-system ...
- 665
16
votes
Accepted
Pending kernel upgrade even after reboot my RPi4
Mixing @Dougie 's comment above and this post: https://www.raspberrypi.org/forums/viewtopic.php?t=270251&p=1639417
the v8 kernel is experimental and should not be used
needrestart is confused by ...
- 431
14
votes
Accepted
Control GPIO pins from C
sysfs has been deprecated and has been replaced with libgpiod.
https://www.beyondlogic.org/an-introduction-to-chardev-gpio-and-libgpiod-on-the-raspberry-pi/
The interactions are with /dev/gpiochipx ...
- 71.5k
14
votes
Accepted
How to revert from rpi-update to stable build
"In normal circumstances there is NEVER a need to run rpi-update as it always gets you to the leading edge firmware and kernel and because that may be a testing version it could leave your RPi ...
- 61k
14
votes
kernel types in Raspbian 10 - Buster
kernel.img is 32-bit for BCM2835 (RPi1 & Zero)
kernel7.img is 32-bit for BCM2836 (RPi2) and BCM2837 (RPi3)
kernel7l.img is 32-bit for BCM2711 (RPi4)
kernel8.img is 64-bit for BCM2837 (RPi3) or ...
- 5,353
13
votes
Accepted
failed to start udev kernel device manager
It might be interesting to know which version you are running, and if you happened to update packages recently.
I encountered a similar error message on my raspberry pi2 after upgrading to raspbian ...
- 146
11
votes
Accepted
iptables: nat table does not exist
Quick guess: You've upgraded the OS and the system has been up for a very long time, or managed to upgrade it without replacing the kernel, because the 4.4.11-v7+ modules have already been removed ...
- 59.5k
10
votes
Accepted
How does the pi know which kernel to load?
All the boot magic is in /boot/config.txt.
kernel:
The alternative filename on the boot partition to use when loading the kernel; the default value is kernel.img.
from official documentation
...
- 357
8
votes
Accepted
Does Raspbian's `/proc/config.gz` contain the running kernel's settings?
Yes; /proc/config.gz, if it exists, always refers to the running kernel's configuration (but see the last few paragraph below) since procfs, like sysfs and devtmpfs, which are used to implement the ...
- 59.5k
8
votes
End kernel panic not syncing cannot allocate swiotlb buffer and cannot provide with dma bouncer buffer
I ran into this same issue with a new install of Pi OS after setting the GPU memory to 896 MB in raspi-config.
To fix it without reinstalling:
Put the SD card in another computer that can read the &...
- 81
7
votes
How compile a loadable kernel module without recompiling kernel
There is a much simpler version here, tested on jessie and stretch.
sudo apt-get install raspberrypi-kernel-headers
and then when your files are in place :
make -C /lib/modules/$(uname -r)/build M=...
- 622
7
votes
Pi 3 Raspbian "stretch" (testing) disables wifi
The package that provides the Wi-Fi firmware is called firmware-brcm80211. To downgrade this package to a version that works:
sudo apt-get install firmware-brcm80211=0.43+rpi5
To prevent this ...
- 171
7
votes
failed to start udev kernel device manager
As of systemd 235-2 this still continues with the exact same error.
For people landing here from google:
If you see that after apt dist-upgrade that either udev, journald or even timesyncd are ...
- 171
6
votes
Raspberry Pi 1 Model B+ end of life?
The rainbow square is an under-voltage warning. You might consider upgrading to a more powerful power supply (more amps, not more volts).
EDIT
To further answer your question I have tried to ...
- 905
6
votes
Wireguard "Unknown device type" "Protocol not supported"
According to a comment on r/Wireguard, this error is caused by having the wrong kernel headers:
dkms packages (wireguard-dkms this time) need kernel headers for
current kernel you have loaded (uname -...
- 295
6
votes
raspberry pi 4B no /dev/spidev0.0
By default, Raspberry Pi installations do not normally enable the SPI functions. Without SPI being enabled, the /dev/spidev0.0 inode is not created. This procedure is taken from https://pimylifeup.com/...
- 161
5
votes
Where do I find the linux headers for an image?
See answer here
https://www.raspberrypi.org/forums/viewtopic.php?f=91&t=154749
You can try sudo apt-get install raspberrypi-kernel-headers if you're running raspbian.
- 111
5
votes
Accepted
How can I troubleshoot kernel panics?
Is there a way to view the entire logs...?
Your Raspberry Pi typically has a serial console enabled (or can be configured to have a serial console) on one of the built-in UARTs, exposed on GPIO pins ...
- 665
4
votes
How to change the default governor?
I made a small programm to change it and let it be changed every boot by automatically creating an init.d script.
Link to my project
- 41
4
votes
How to use the perf utility on raspbian?
I was able to install the perf package using sudo apt-get install linux-perf-4.9. Use uname-r to find your kernel version, and apt-cache search linux-tools to find the proper package name.
- 141
4
votes
Accepted
Is it possible to run Raspberry Pi 3 with a 64-bit kernel and 32-bit user space?
Is it possible to run Raspberry Pi 3 with a 64-bit kernel and 32-bit user space?
Yes. Some pre-built images have this ready to go:
Crazyhead90's Raspbian Stretch Lite and Desktop 64-bit images (Pi 3,...
- 2,922
4
votes
Linux headers generic package not found
Run below command on the terminal to install
sudo apt install raspberrypi-kernel-headers
- 141
4
votes
Check system name and kernel version in script
Here's something which takes a different twist on /etc/os-release, which has a standardized format based around setting shell variables, meaning you can source it and use them. First have a look at ...
- 59.5k
4
votes
How to boot raspberry pi very quickly into Linux?
You can build linux from scratch on the pi (http://www.intestinate.com/pilfs/guide.html). With a custom kernel, you can boot into systemd in < 1s.
- 141
4
votes
Accepted
Installed kernel headers and $(uname -r) differ
You can restore your system to standard with
sudo apt-get update && sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel
sudo apt-get install raspberrypi-kernel-headers ...
- 61k
4
votes
My Adafruit PITFT stops working after sudo apt-get update
Per the Adafruit Help! FAQ:
Doing an apt-get upgrade or rpi-update will blow away the custom PiTFT
kernel.
You will have to reinstall the kernel.
If you had already made a working PiTFT setup, ...
- 34.8k
4
votes
How can I troubleshoot kernel panics?
Addressing Point 2
...and how do I troublshoot kernel panics?
A kernel panic is just a crash inside the kernel. A crash caused by any number of normal software or hardware faults.
Debugging the ...
- 3,003
4
votes
Accepted
What repository to add for apt to find raspberrypi-kernel?
I got it. I thought to be on the safe side by copying the whole /etc/apt directory-structure to the bootstraped raspi. But that was too much. I only have do add the archive-address for the raspberrypi....
- 42.4k
4
votes
Linux modules mismatch version
Stefan's problem could be a bit like mine.
I installed Raspbian Stretch on an SD card but then did that thing of putting the root file system on USB and changing /boot/cmdline.txt to point to it.
What ...
Only top scored, non community-wiki answers of a minimum length are eligible