build is missing for compiling kernel module
this is my first time trying to create a kernel module, apparently after creating a module I need to follow these steps to compile it:echo "obj-m := Hello.c"> Makefile make -C /lib/modules/`uname...
View Articlehow to make a module install in linux
im new to linux , and im using linux clear distributionim trying to conect my DSLR to be like webcam trying make this module to install and it not working this is my output $ make Building...
View ArticleUnable to find mlan0 wireless connection
This is happening on an Owasys microcontroller running Debian 9, yesterday I managed to get Wi-Fi turned on but today it does work and connection is not listed.lsmod returns a list of devices which...
View ArticleNotify user-space about interrupt, sleep otherwise
As a beginner, I want to know what people think would be the best course of action for the following scenario. I have a driver that handles a rising-edge interrupt on a gpio pin. The driver also has a...
View ArticleWhat is a good way to capture task_struct values on every context switch?
I want to collect a list of values from the task_struct of a specific process (I know its name) on every context switch. What is a good method to achieve this?
View ArticleHow to detect memory safety errors in a linux kernel module?
For the past week, I was working on a simplistic kernel module that creates a character device driver that allows the passing of messages between user and kernel space.All good and nice, I found KEDR...
View ArticleLoading a kernel module at boot time is blocking?
I am loading a kernel module at boot time, I added it to a config file in /etc/modules-load.d/, the module is loading correctly.In my module I am using the wait_for_random_bytes() function from...
View Articleuser space address dereference in kernel [migrated]
I have allocated user space address using compat_alloc_user_space api, but sometimes de-referencing this pointer or address would cause page fault in 4.X kernel, but de-referencing in 3.x kernel works...
View ArticleLinux character device driver won't respond to head command
I am writing a LKM to create a character device driver.Linux Kernel: 4.4.0-93-generic in VirtualBox, 2GB ram and SWAP is 300KbProblem 1If I write a C program that handles the fd in dev_write, it's all...
View ArticleLinux character device driver issues
I am writing a LKM to create a character device driver.Linux Kernel: 4.4.0-93-generic in VirtualBox, 2GB ram and SWAP is 300KbProblem 1If I write a C program that handles the fd in dev_write, it's all...
View ArticleDo all threads originating from the same process sleep on...
If I have 3 pthreads: A, B, C, all originating from the same process, running in user space and one thread, thread B does a blocking read from a kernel module and is put to sleep, will threads A and C...
View ArticleKernel space memory deallocation freezes kernel
I am writing a kernel module. Reads bytes from user space and writes back. static ssize_t dev_read(struct file *filep, char *buffer, size_t len, loff_t *offset) { Node *msg; int error_count = 0; //...
View ArticleHow to restart a failed amdgpu kernel module
My video card crashes from time to time. It's quite annoying but I live with it -- usually I just restart the graphics with sudo systemctl restart lightdm.service, or if needed reboot the whole system....
View ArticleIs there a limit to the number of USB gadget can be created with configfs?
OS: Ubuntu 18.04.3 Kernel: 5.3.8Hi guys :) I'm trying to create bunch of HID gadgets by using configfs. It was successful until setting up fourth gadget, but kernel emits error message during creation...
View ArticleCompile Linux kernel module without .config
I have an embedded Linux device based on BusyBox which doesn't ship with WiFi drivers. I'd like to make WiFi work by compiling the rtl8192cu driver for it (for the wifi usb dongle I have).The device is...
View Articlerts5139/rtsx_usb borked in 3.15+
Some time in 3.15, someone moved the rts5139 driver out of staging (I cannot find a changelog of this) and it got renamed to rtsx_usb. This, unfortunately, broke support for at least the RTS5139 card...
View ArticleNvme not showing up in /dev on Ubuntu 19.04 (5.0.0-13)
I have an Ubuntu 19.04 on a machine with an nvme drive. However, the drive is not found in /dev/nvme*. cat /proc/devices shows that nvme is loaded as a character device and not a block device and lsmod...
View Articlemake command not working
/rtlwifi_new# make && make install make -C /lib/modules/4.12.0-kali2-amd64/build M=/root/rtlwifi_new modules make[1]: *** /lib/modules/4.12.0-kali2-amd64/build: No such file or directory. Stop....
View ArticleRadeon GPU not found after kernel upgraded to CentOS 7.5 - "[AMD/ATI] display...
My system has a three monitor setup:Monitor 1 connected to the onboard i915 chip Monitor 2 & 3 connected to a Radeon RX 560 GPUThis configuration worked until I upgraded CentOS to the...
View ArticleOn most linux systems, why is the KVM kernel module loaded even when you're...
Recently I started looking at KVM/Qemu as an alternative to VirtualBox and was shocked to notice that these 3 modules seem to be automatically loaded on almost every linux system I checked:[pgoetz@frog...
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