Kernel Questions

I'm working with a few kernel modules (4.19.97) and i allocate struct my_sock like the following. struct my_target {

This can be a silly question as i do not know much about this topic at all... it seems that user applications can talk directly to gpu to render

So, i was trying to install a hello world kernel shown the book "linux device drivers" by corbet, jonathan. this is the code for

I'm trying to complete an assignment for an operating systems course,

I want to print 12byte from specific memory address in kernel. following is my hard coding. void *unique_id = 0x5c000234;

I am learning how to write some code in the linux kernel, and i would like to start practicing writing code in the kernel, but my question is what

pword exported_ordinalstable = (pword)((ulong64)kernel_module_base + p_export_dir->addressofnameordinals); pdword

I'm writing a can logger program. the way i log the data is similar to the way the candump-tool is doing it when invoking

The "os161" operating system contains the following code. specifically, where the syscalls are defined: ...

I am trying to understand the definition of a linux macro s64_min used in the following else condition i.e. draw

I'm a newbie in linux driver field.now, i has just done with writing linux driver and i'm testing the accuracy of the function of this driver. the

I'm trying to keep track of the number of writes per physical page in the file "proc/pid/pagemap".but the file is binary, and the size

I've skimmed through the linux kernel module programming guide, but

I have a simple kernel module which creates a sysfs node under /sys/class and adds a test attribute to the class. the test attribute has a store

I was always attracted to the world of kernel hacking and embedded systems. has anyone got good tutorials (+easily available hardware) on

I am trying to make kernel (android, kernel 4.9.59) communicate with userspace applications. i found a solution using netlink sockets:

I am currently learning more about ctypes and its functions and what i'm trying to do is to create a script to

We need to connect a lvds screen to an apq8096 platform so a mipi-dsi/lvds bridge has been chosen to convert mipi bus to lvds. the bridge used is

I'm porting android to a display device, and have nearly completed this. the device use the freescale/nxp i.mx6 dual lite soc. the android version

Following is my device tree: can anybody correct this code, i'm new to c and driver development, how to access members of a nested struct

In linux 5.4.21 source code include/linux/irqflags.h, #define raw_local_save_flags(flags) \ do {

I am compiling android kernel 3.18. i am getting this error drivers/built-in.o: in function `enable_extldo':

When an executable is running on linux, it generates processes, threads, i/o ... etc, and uses libraries from languages like c/c++, sometimes

I'm currently working on a lkm to intercept some syscalls for printing statistics about them system-wide. i've come across different ways

I'm trying to use sage in anaconda 3 but it looks that the libraries are not imported. i firstly created a new environment 'ipykernel_py2'

I am writing a sample program where my main() will create a thread and then it will start a timer. when the timer expires, the thread should get

In most languages, c included the stack is used for function calls. that's why you get a "stack overflow" error if you are not careful in

I am trying to debug a rootkit in a virtual environment. from reversing i know that it uses super simple cpu timing checks, that look something

I've been trying to figure out how the __list_add function works in the linux kernel implementation of a linked list. here are

The below manual on system() says it blocks sigint and sigquit signal for any binary program run through system() call.

I was trying my hands on addr2line to convert a "pc" register value from a kernel oops

I am trying to write a c sniffer for linux, and understand the actions happening in the kernel while sniffing. i am having troubles finding

I never found the definition for scull_follow in the book, so i'm trying to understand it based off a github

I modified the linux kernel code so it drops the first tcp connection request if the syn backlog contains more than 9 connection requests as shown

I am playing with liburing and io_uring, the former is built from the master branch and for the latter i am using the kernel 5.8.0-rc3. i

I'm trying to understand how to use the linux kernel spinlocks. from reading the header, i think i have to first declare one and initialize it

I am passing a string to the ioctl function using a pointer to a userspace struct with the parameters. my struct contains a pointer to the string,

I am trying to create a logging middleware for when my commands run. the logger is working when a user makes an http request but i can't figure

I have been making a kernel-level dll injector for about two weeks. i have fought through a ton of bugs and learned a lot from them, but i am

I have a custom bootloader booting into a custom kernel. i'm writing in c now the assembly is out of the way. so far, local

I am new to opencl and learn it from

I tried to redo the code of the kernel module found in this topic

I'm trying to create an os kernel in educational purposes. using

Imagine the following use-case: static atomic_t ref_counter = atomic_init(0); void

I'm trying to build linux kernel module: kbuild_extra_symbols := ../../module.symvers kbuild_extra_symbols :=

I read stevens' example on passing descriptors between processes. to summarize, his main program forks a child which exec another program, which

I have a binary from which i need to intercept a certain syscall--in this case unlinkat--and make it do nothing. i have the following

I'm curious how a single nptl thread exits, from implementation perspective. what i understand about glibc-2.30's implementation

In the following link i have the following

Hello i am trying to compile my first kernel module but i am receiving an error message. the hello.c program for my module is shown below:

Hi im am customizing linux kernel with version 2.22.19 and it do not support device tree. so i must use board init code to describe the

When reading linux kernel source code, i find one thing makes me confused. in task_struct, it says like this

What i want: to add a network namespace option to execsnoop bcc tool to trace only the logs with specified

As per the documentation(https://lwn.net/articles/17744/), which says

Here is my graphic card: 03:00.0 vga compatible controller: advanced micro devices, inc. [amd/ati] caicos [radeon hd

I am trying to ensure proper synchronization over a piece of memory shared between a user thread and another thread running in kernel mode on

I have created a set of shortcut macros for linux kernel

I trying to understand the internals of the linux kernel by reading

I get invalid access to packet from the ebpf verifier even though i'm performing a check before accessing a byte from a packet. the

I have a makefile that compiles two linux kernel modules (mod1.c and mod2.c). obj-m = mod1.o mod2.o

I have a linux kernel module that checks for the presence of a specific usb device and performs a printk upon a match. this code works fine and

I am reading robert love's

I'm trying to understand how to instruct the cpu to instruct a pci device to map its memory to the physical address of the cpu. i've read

I want to use crypto api and i found linux kernel documentation about it.

I have a driver which is, for some unknown reasons causing a bugcheck 0x0000003b. so i decided to set up a hyper-v vm and use kernel

I'm writing a linux device drive and i'm confused as to why i'm getting this warning. error: initialization from incompatible

The problem is to prohibit access to some files (files from my "blacklist"). it implies that nobody besides me (my own kernel module) can either

I have a question about linux workqueue. i found example kernel module using workqueue and tested it. here is the code. #include

Is there a way to check whether a given pid matches any process in kernel space? i am building a system call that changes the weight of

I am writing a simple driver, which could register an interrupt and handle it. i am using the request_irq function but it returns

There are some cases when it is needed to see the full log of linux kernel panic. but it often can't be done through the regular terminal in

I am totally beginning in linux kernel development. i am trying to learn about processes and scheduling (i know what i want to do is not "useful"

I compiled linux kernel 5.6 in user mode with my custom initrd, created with following method: mkdir initrd cd initrd mkdir bin

Why do we need to define two types of barriers with the same implementation?

I'm writing ioctls handler for kernel module and i want to copy data from user space. when i'm compiling code with disabled optimizations

I've been building a rtdm uart driver by using the linux version as an example. the uart base address is supposed to be 0x80070000,

I want to understand this error. printing uid of a process, code: printk(kern_info "user id = %d\n", (task)->cred->uid);

I whish to compile two kernel modules (out of tree) that share a common library : module1.c uses functions from library.c and module2.c also uses

Can anyone explain what this macro evaluates to: #define memcpy(dest,src,n) ({ \ void * _res = dest; \ __asm__ ("cld;rep;movsb" \

I'm currently writing a custom kernel. i've remarked that none of my declared global variables gets initialized to the correct values. here's an

Here's the code from rt_imx_uart.c : static ssize_t rt_imx_uart_write(struct rtdm_fd *fd, const void *buf,

I am trying to understand the call flow of the ioctl call in linux kernel and i have a question - when we call ioctl from userspace, which

As hinted from my title, i am interested if it would be possible to allocate a c array, and make it behave like a stack by pointing esp register

I want to have a fixed size integer of 64 bits in linux kernel. my questions: if i use unsigned long, then it

I am learning linux wifi drivers, and was exploring the code in cfg80211 subsytem for a scan request. i can't understand why

As i was studying the code of the mxs-auart.c driver i noticed the following declaration: enum mxs_auart_type {

In the /proc directory a custom module should create two directories lkm and mem to get a hierarchy like /proc/lkm/mem.

I've wrote a simple code to test the function time() from time.h: // time-test.c #include

I'm writing my own kernel (using multiboot2) and have followed this

I'm trying to understand and use the kernel

From linux's proc.txt: memtotal: total usable ram (i.e. physical ram minus a few reserved but how to get the

How can i tell the compiler not to optimize and not to add any other instructions in between, and force the cpu to execute them back to back?

I'm trying to send a struct from user-space to my module in kernel space using netlink, my struct in the user-space is: struct

I'm trying to build a small demonstration kernel module for linux which finds a specific process and reads a value from that process' memory.

I am reading through linux v3.19's implementation of pid namespaces and in pid_namespace.h there are functions defined that are

Is there a way to get to know what kernel functions are called during a certain event. for example, if i press any key on keyboard, i want

I write a kernel module that uses kernel threads and semaphores. i call up(...) function for semaphore from interrupt handler

To allocate memory i do like that: uint64_t _addr = 0x00; kern_return_t err = mach_vm_allocate(mach_task_self(), &_addr,

They are similar functions, but what is the exact difference between them? the linux documentation states: note: use

Title may be a bit confusing, as i am having trouble describing it. i am sure this is already asked but i have no idea how to properly