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327 votes
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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 ...
Peter Green's user avatar
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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 ...
Rebroad's user avatar
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25 votes
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How compile a loadable kernel module without recompiling kernel

First of all, make sure you use the proper kernel headers. I assume that your kernel headers and source code are more updated than the kernel you're running. Try to do an apt-get update && ...
Aloha's user avatar
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23 votes
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conflicting dtoverlays

As it turns out several overlays can be loaded by adding multiple dtoverlay variables: In this case: dtoverlay=4dpi-3x dtoverlay=w1-gpio
user1217949's user avatar
16 votes
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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 ...
Olivier's user avatar
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14 votes
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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 ...
joan's user avatar
  • 70.9k
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 ...
Dougie's user avatar
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13 votes
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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 ...
EThome's user avatar
  • 146
12 votes
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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 ...
Milliways's user avatar
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11 votes
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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 ...
goldilocks's user avatar
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10 votes
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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 ...
SiKing's user avatar
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8 votes
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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 ...
goldilocks's user avatar
  • 58.7k
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 &...
Cole P's user avatar
  • 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=...
pim's user avatar
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7 votes
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Raspberry Pi cannot create temp file for here-document: No space left on device

Run the command sudo raspi-config and select the Expand Filesystem option. Then you should be good to go.
Patrick Cook's user avatar
  • 6,365
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 ...
NobodyNada's user avatar
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 ...
wadge's user avatar
  • 171
6 votes

Low Energy Consumption Kernel

The kernel already consumes negligible power. The software loaded on the pi would be the ones munching the most power because of processor time (Apache, databases, networking, etc.) Here are some ...
Aloha's user avatar
  • 7,126
6 votes
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Linux headers generic package not found

I also came across this problem and solved it by following the instructions for a similar question on this forum. However I did need to make some changes. Specifically, I had to run the following ...
Sandro Gauci's user avatar
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 ...
88weighed's user avatar
  • 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 -...
ki9's user avatar
  • 295
5 votes
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Essential parts for booting the Raspberry Pi 2

What do I need to sucessfully boot my Raspberry Pi 2 until the init system is loaded? I think I need only the files on the boot partition, because /sbin/init is a symlink to e.g. systemd. /sbin/init ...
goldilocks's user avatar
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5 votes
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Recover pi 2 from wrong kernel build?

All the boot files are on a FAT32 sector, which is readable and writeable by all common operating systems. You can place the SD card in an SD card reader, delete the bad kernel, and rename the good ...
joan's user avatar
  • 70.9k
5 votes

Cross-compile x86-64 code on Raspberry Pi 2

It is possible to compile x86_64 code on the Raspberry Pi, and i have just built a cross-compile toolchain on my Pi 2 (with more than 27 hrs of compilation and some hours of bug fixing). You can ...
Kong Chun Ho's user avatar
5 votes
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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 ...
larsks's user avatar
  • 656
4 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.
Dip's user avatar
  • 101
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
MeisterD's user avatar
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.
Josh Peterson's user avatar
4 votes

How to make a distribution bootable on raspberry pi / package migration from 32-bit x86 Debian install?

As I mentioned in chat, this project isn't possible as is. As with an engine in a vehicle, computer processors can very dramatically. A boat, plane, train, and car all have an engine, designed to ...
Jacobm001's user avatar
  • 11.9k
4 votes
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Raspberry Pi-2 with mainline Linux kernel

While the Raspberry Pi 2 support is present in 4.5, you're also looking for a .config that will work. The changes for multi_v7_defconfig weren't ready for 4.5, so they're currently in linux-next. ...
Emma Anholt's user avatar

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