High kernel memory usage in Kubernetes Node
I am pretty desperate searching for a solution to this. I am running a Kubernetes Cluster (v1.16.7) on AWS.Node specs are: It is an Amazon EC2 t3.medium instance with 4GB RAM and AMI:...
View Articlemakefile: "no rule to make target 'arch/x86_64/Makefile'" linux kernel 2.2.0
I'm trying to config my kernel (2.2.0) but when I use make menuconfig make says: No rule to make target 'arch/x86_64/Makefile'. It is a wrong response because there is no directory named x86_64 in...
View ArticleRE: How to obtain Linux syscall name from a syscall number?
I am trying to write a Linux kernel module to get the name of a syscall given its syscall number.For example, with the syscall number 64, I want it to return the name semget.I found a similar question...
View ArticleWhy does general-purpose register w0 change value in arm64?
I am having a kernel crash issue in ARM64 (or aarch64). My system has 4 cores.I investigated the issue and find out some points.Here is the code C (linux/drivers/cpuidle/governors/menu.c)static int...
View ArticleIncluding external assembly functions from a .asm file into a .h C header file
I have a C header file cpu_checks.h that declares an extern function, which is implemented in an assembly file cpu.asm.cpu_checks.h:#ifndef CPU_CHECKS_H#define CPU_CHECKS_H extern int...
View ArticleHow to run a EXE file through python on Linux environment
I am working on the Linux environment. I need to call the EXE file from the local path through python. I have tried the below code it didn't execute. Suggest a...
View ArticleHow to write a kernel module to lookup route table and arp cache in kernel?
I want to write a module to lookup the route table in kernel for getting the gateway ip, and use the ip to lookup arp cache for getting the gateway's mac address.
View ArticleClik here to view.
Translate virtual address to physical from multi-level pagetabels
I'm trying to convert an virtual memory address to a physical one, but can't get it to work. I'm currently doing an operating system as an assignment, and now I have to implement a printf function for...
View ArticleHow to use an own device tree and modified kernel config in Yocto?
I am working to build an own "embeeded linux" with yocto. It is based on the SAMA5D3x-MB + SAMA5D3x-CM(RONETIX) with the SAMA5D35. I have two questions:1.) changing the device treeI build an image...
View ArticleSR-IOV: packets to a VF attached in a Virtual Machine
In SR-IOV enabled NICs we can create some number of virtual functions (VF), and attach those to virtual machine. This is my very rough understanding, so I'm sure I:m missing details.Does it mean that...
View Articledo_sys_open kprobe is always returning the same filename
I wrote a module which registers kprobe on do_sys_open and i am trying to print the filename in the pre_handler#include <linux/kernel.h>#include <linux/module.h>#include...
View ArticleWriting x86_64 linux kernel module in assembler
I try write simple kernel module (v3.6) in nasm, but insmod say me:$ sudo insmod ./hello.koinsmod: ERROR: could not insert module ./hello.ko: Invalid module format$ echo $?1I compile my code with:$...
View Articleunderstanding arm64 assembly (adr_l, ldr_l, str_l, ..) in a linux kernel code
This is an assembly code from linux arm64 (arch/arm64/kernel/head.S).(kernel source 5.4.21)__primary_switched: adrp x4, init_thread_union -- line 1 add sp, x4, #THREAD_SIZE -- line 2 adr_l x5,...
View ArticleCannot find the appropriate linux header
DISCLAIMER: Maybe this type of question is not appropriate for Stackoevrflow. If that is the case, I apologize. I would also be glad to hear what is the proper case to ask :)I have the following OS...
View ArticleWhat the documentation of Linux Programmer's Manual is documenting?
I have worked with the manual page of the socket() in my Linux system and I was wondering what the functions it is documenting are belonged to.For example, the function int socket(int domain, int type,...
View ArticleAbout building a very small linux kernel with the bare minimum compiled-in...
How to configure Linux Kernel?I found two applications: lsmodconf and modprobed-db also one web page about building a very small kernel with the bare minimum compiled-in and all the rest as...
View ArticleHow can I create a Bulk USB Gadget WinUSB Device
I created an small embedded WinUSB device which offers 2 bulk endpoints. This device can communicate with Linux and with Windows10 without installing driver, or a .inf file.Now we want to use the same...
View ArticleMeasuring execution time of a function inside linux kernel
I am using Linux Security Module hooks to add some custom functionality to recv() system call. I want to measure the overhead of this functionality as compared to the pristine recv(). I have written a...
View ArticleWhy save init_task struct address to sp_el0 in arm64 boot code...
This is an assembly code from linux arm64 (arch/arm64/kernel/head.S).(kernel source 5.4.21)__primary_switched: adrp x4, init_thread_union -- line 1 add sp, x4, #THREAD_SIZE -- line 2 adr_l x5,...
View ArticleHow are memory regions on ARM Cortex A denoted as "device" or "strongly...
On the ARM Cortex-A9 that comprises part of the Zynq SoC I'm using, regions of memory are labelled as "normal", "device" or "strongly ordered". This is described in the Zynq technical reference manual,...
View Article
