Questions tagged [kernel]

The kernel is the central component of the operating system and manages hardware, process scheduling, file systems, virtual memory paging, inter-process and network communication, etc.

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16
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4answers
14k views

Kernel .config necessary options

I'm interested in compiling a custom kernel for the pi. I have the source from the github archive, which includes a make target for a default configuration: make ARCH=arm bcmrpi_defconfig But (as ...
65
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1answer
65k views

How does Raspberry Pi boot?

I have a raspberry mini computer and I am wondering how that thing does whole the boot process. I can compile my own kernel and init ramdisk with my own scripts and build my own minimal linux system ...
1
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1answer
1k views

Linux based cross compiler [duplicate]

I need an ARMv6 cross compiler for my B and B+ pis, primarily for building the kernel since this requires many hours on the pi itself and sometimes requires trial and error to get right. I would also ...
15
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2answers
18k views

Enable monitoring mode for RTL8188CUS via USB on Raspbian

I am trying to enable monitoring mode for a USB wifi dongle with the RTL8188CUS chipset on a raspberry pi model b+ (or any raspberry pi for that matter). $ lsusb Bus 001 Device 005: ID 0bda:8176 ...
21
votes
3answers
33k views

How compile a loadable kernel module without recompiling kernel

I have read quite a bit about how to compile a kernel module on (and for) the Raspberry Pi, but I'm still not quite able to figure out why it's not working. I have been able to build the module, but ...
9
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2answers
3k views

Control GPIO pins from C

Most of the libraries, in multiple languages, interact with the GPIO pins via /sys/class/gpio/export, /sys/class/gpio/import, /sys/class/gpio/gpio10/value, etc. However the linux kernel docs clearly ...
1
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2answers
2k views

LIRC Tutorial For Rpi2B+ Buster Too Old Problem

I'm trying to set up lirc on a Pi2 B+ running the latest Raspbian buster and latest kernel / firmware set by rpi-update. I've started from this HOW-TO. All I get from sudo modprobe lirc_rpi is: ...
19
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5answers
28k views

Emulating raspbian with QEMU

I'm trying to emulate raspbian on QEMU and there're plenty of guides available on internet. However, every guide points to download qemu-linux kernel from link https://xecdesign.com/downloads/linux-...
5
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3answers
27k views

Kernel panic, unable to mount root fs on unknown-block after restart

My Raspberry Pi has been hosting a small site from home for a few days, and everything was working fine. It's completely headless, so I use SSH for everything. This morning however when I woke up, I ...
3
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3answers
3k views

DHT11 module compilation error

I try to compile the source code of DHT11 module given in [https://www.endian.se/content/?p=127] . I have followed the step of KERNEL compilation in [[http://bchavez.bitarmory.com/archive/2013/01/16/...
129
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2answers
88k views

What is rpikernelhack?

When doing an apt-get upgrade on my RPi 3, many lines of output show up like this: Adding 'diversion of /boot/bcm2708-rpi-b-plus.dtb to /usr/share/rpikernelhack/bcm2708-rpi-b-plus.dtb by ...
14
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2answers
18k views

building kernel image (.img) including ramdisk

I have built my Linux kernel (3.0.1) for my Raspberry Pi with these following steps: 1. Downloading kernel source 2. tar xvf source.tar.bz2 3. downloading arm cross compilation tool. 4. tar xvf arm-...
13
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5answers
39k views

How to change the default governor?

I want to change the default governor on my pi from ondemand to performance. Is there a way of doing this?
19
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2answers
46k views

What kernel parameters are available for fixing USB problems

There's a lot of problems with USB stack on Rapsberry Pi and developers are working hard to fix as many of them as possible. They introduce some kernel modules options (like dwc_otg.fiq_fix_enable) ...
14
votes
4answers
21k views

Where is the kernel source for Raspbian's default 3.1.9+ kernel?

The default kernel version of Raspbian is 3.1.9+. When I try to compile an extra kernel module I have lots of error messages since the kernel header files are missing. I've checked the Raspbian ...
7
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2answers
4k views

Arm timer in kernel module with precision less than microsecond

Good evening, i'm asking your help, to understand how to use a timer in kernel module to achieve periodic task with period less than a microsecond. I was searching on the web and i've found that ...
2
votes
1answer
4k views

Install Custom Kernel

I have a custom linux kernel I need to use. I have the source tree and seem to have cross-compiled it correctly. I don't need help with that, but I don't know how to now install and use the kernel. ...
6
votes
1answer
6k views

kernel panic not syncing: VFS unknown-block 179,6 after cloning SD

I have set up my Raspbian and need to clone the SD Card to about 20 other Raspberry Pis now. I used the following command (on OS X) to clone the SD Card: sudo dd if=/dev/rdisk3 of=~/Desktop/pi.img ...
6
votes
1answer
2k views

Raspbian kernel module segmentation fault

My Raspberry Pi currently runs 3.6.11+ #538 (obtained from uname -a), which may be the source of my issues. I'm starting to write a kernel module using the following "Hello World" code: #include <...
3
votes
1answer
7k views

How to get kernel source corresponding with the kernel installed by rpi-update

After an upgrade using rpi-update the kernel could be upgraded. The script download the kernel from an other gihub repository rpi-firmware. Till now, in order to get the kernel source, I download ...
3
votes
0answers
3k views

TFT Kernel module not loading on startup

I'm not able to load a driver for a TFT display permanently on a Raspberry with Raspbian OS like specified here: fbtft_device name=sainsmart18 verbose=0 in /etc/modules. Whenever I restart the ...
2
votes
2answers
13k views

Colored screen when booting raspbian from noobs

i have a raspberry pi model b with noobs and raspbian installed on the sd card. ive used it for quite a while but today when i boot the pi it just shows me a colored screen and i cant do anything. i ...
1
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2answers
7k views

Kernel panic-not syncing: VFS: unable to mount root fs on unknown- block(179,6) running Raspbian NOT on top of NOOBS

I tried many fixes, but most of them are for NOOBS Raspbian installations, not for a clan Raspbian installation. I got the following Kernel Panic error: Kernel panic-not syncing: VFS: unable to ...
0
votes
1answer
300 views

raspi-config is not working after installing Xenomai on Raspberry Pi 3

I followed the instructions given here to install Xenomai on a Raspberry Pi 3. After installing the kernel (now the RPi uses the kernel-xenomai.img during boot) I couldn't access my network, neither ...
18
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2answers
41k views

How do I upgrade Raspbian?

I have my Raspberry Pi setup how I want, but I have an older version than what is currently available (2012-10-28-wheezy-raspbian.zip). How do I upgrade the kernel, firmware, etc.? I have upgraded ...
17
votes
1answer
4k views

What is the difference between Raspbian kernels in official image?

In the official Raspbian "wheezy" image (2012-07-15), there are three Kernel images: kernel.img (6MB) kernel_cutdown.img (4MB) kernel_emergency.img (16MB) I'm curious what are the technical ...
6
votes
4answers
15k views

Linux headers generic package not found

I need to compile this driver, however I'm missing my kernel headers. I've tried installing them the normal way: sudo apt-get install linux-headers-generic Package 'linux-headers-generic' has no ...
17
votes
5answers
19k views

Cannot Emulate Raspberry Pi using Qemu: Kernel Panic

I am trying to follow various guides on the Internet in order to emulate Raspberry Pi on my Fedora 22 machine. I have found this question: Emulating raspbian with QEMU and used it to find kernel-qemu ...
7
votes
4answers
9k views

Pi 3 Raspbian “stretch” (testing) disables wifi

I have a raspberry pi 3 (which has internal WiFi), running raspbian. I decided to run it as "testing", by changing the apt list. Now, I can't use WiFi. Whenever I use wpa_supplicant, it complains ...
4
votes
3answers
3k views

How to build My own OS for the raspberry or configure an existing one

I'm using Raspbian with raspberry pi 2 ... But i want to customize it and remove some features that i don't really need , to take advantages on the performance and also to understand the procedure of ...
8
votes
3answers
7k views

How to use the perf utility on raspbian?

I'd like to use the perf tool on my 2016-02-09 Raspbian Jessie operating system. For that, I have installed the linux-tools package (which contains perf). The kernel version in use on that image is 4....
8
votes
2answers
3k views

How can I troubleshoot kernel panics?

My Raspberry Pi 3 has been working stably for a year now as a headless server. In the last month, it's started crashing frequently (every two days). I can attach a monitor and see that there has been ...
3
votes
2answers
10k views

How to get a specific kernel version for Raspberry Pi Linux?

I'm trying to find the source for version 3.12.20, but the current 3.12.y version on GitHub is 3.12.24. I understand I can just update my current version, but shouldn't downloading the source for my ...
6
votes
3answers
3k views

Wireguard “Unknown device type” “Protocol not supported”

I recently installed Raspberry Pi OS on my Pi 3b. After some basic configuration and running raspi-config, I installed wireguard using apt and the debian backport repos, according to a tutorial. I ...
4
votes
1answer
1k views

Periodic task in kernel module

I currently developing a gpio based kernel module for a custom protocol. As per requirements of protocol, I have to send data, clock and enable signal to output device throgh gpio. This data is 16-bit....
3
votes
1answer
2k views

How to tell if I am running the latest version of the Raspbian kernel?

I just finished building the Raspbian kernel according to the instructions in Raspberry Pi Kernel Compilation Guide. Prior to this I was running the latest build from raspberrypi.org, 3.6.11+ #358. I ...
2
votes
1answer
781 views

Can't mount volume encrypted with aes-xts-plain64 after upgrading to Jessie

I have an encrypted disk attached via USB. After upgrading to Jessie, I'm not able to mount it any more, getting error Check that kernel supports aes-xts-plain64 cipher (check syslog for more info) ...
2
votes
1answer
3k views

Raspberry Pi freezes during boot

I can't get past the attached picture. Nothing happens anymore. The red light is always on. I don't have anything plugged in the USB. It just stays there, and the cursors continues blinking. Also, at ...
2
votes
1answer
3k views

Does Raspbian's `/proc/config.gz` contain the running kernel's settings?

For regular Debian the kernel configuration is stored in /boot/confg-<version>. I looked for Raspbian's equivalent but did not find it there. However, as also mentioned and thanks to this and ...
1
vote
1answer
2k views

Installing ESP8266 SDIO driver; “make” command gives “Kernel build tree not found” error

I'm attempting to add a kernel module on a Raspbian Debian installation for an SDIO-based wifi module driver( found here: https://hackaday.io/post/28712) The stable image comes with kernel 4.1, so ...
0
votes
4answers
4k views

Linux modules mismatch version

I have a very unusual condition, perhaps a partial update or unknown condition. #>uname -a Linux sip02 4.14.30-v7+ #1102 SMP Mon Mar 26 16:45:49 BST 2018 armv7l GNU/Linux #>uname -r 4.14.30-v7+...
4
votes
3answers
3k views

Multiplexing 4-digit 7-segment display is flickering

I connected a 4-digit 7-segment display to the GPIO-port. It uses 8 ports for the LEDs and 4 ports for multiplexing via PNP-transistors. It is running so far with a loop written in C program: while(1)...
4
votes
2answers
1k views

Raspbian - Real Time Kernel does not boot

I am trying to make a Raspbian kernel to support real time. To do that I cloned the latest kernel from raspbian github repository and applied the Real Time patch for 3.10.25-rt23 (https://www.kernel....
4
votes
3answers
11k views

Raspberry Pi 1 Model B+ end of life?

TL;DR My Raspberry Pi (Model B+) can't run the newest Raspbian (Stretch), suspected is that the kernel doesn't work. Anything with a kernel version above 4.1.19 will fail to load. Does this mean that ...
3
votes
1answer
551 views

Is the Raspberry Pi 4 vulnerable to the Spectre exploits?

Now the new Raspberry 4 has moved to ARM A72 cores, it's vulnerable to the spectre issues according to ARM. Processor Variant 1 Variant 2 Variant 3 Variant 3a Variant 4 Cortex-A72 Yes Yes**...
3
votes
2answers
2k views

Run a script when wifi is connected to a particular wifi network?

My Raspberry pi is connected to my home wifi network. This wifi network have a captive portal and hence each time I need to sign in the captive portal to use the internet. Now I am trying to automate ...
3
votes
1answer
6k views

PANIC: VFS: Unable to mount root fs on unknown-block(179,2)

I unplugged my RPi (RPi#1) and moved it to another power outlet, and plugged it back in. RPi#1 is the brains of my distributed setup, containing the database and biggest SD card. All of the data my ...
2
votes
3answers
10k views

Compile linux device driver in Raspbian

I have some problems with compiling & building a simple gpio driver that I wrote( after THIS documentation). I have a Raspberry Pi Model B+ ( not sure if it's relevant to the question) with a ...
2
votes
1answer
462 views

spi stopped working after upgrade

I recently ran apt-get dist-upgrade on my Raspberry Pi B. Afterwards the spi-devices /dev/spi* were gone. This is the changelog of the upgrade: Package changes: +device-tree-compiler 1.4.1-1+rpi1 +...
2
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4answers
1k views

Which kernel source is required to compile for Raspberry Pi?

I am trying to compile and build a kernel image for Raspberry Pi. I build my customized cross compiler tool-chain for Raspberry Pi using Buildroot. Successfully I got all tools which I needed. I ...