linux kernel poster

The previous chapter describes how to compile the Linux kernel. After an image is obtained, it can be burned to the Development Board for running. However, this will also cause some problems: for example, if you want to add or modify some Linux kernel configurations and components, you must re-compile the

Refer to this How to Remove the old (or new) kernelshttp://ubuntuhandbook.org/index.php/2015/08/install-latest-kernel-script/1. In Ubuntu with a graphical interface:1.1 Installing synaptic Package Manager in Ubuntu Software Center1.2 Deleting packages using Synaptic Package Manager: Click the Reload button in the want to remove the new kernel. Select Status-installed on the left pane to make se

How to remove the old kernel after Linux kernel upgradeFirst we need to look at which kernel is currently in use: Uname-r This command will tell you the kernel version currently in use Next, if you are compiling the kernel you

Linux Kernel 'arch/x86/kernel/cpu/mcheck/mce. c' Local Denial of Service Vulnerability (CVE-2018-7995)Linux Kernel 'arch/x86/kernel/cpu/mcheck/mce. c' Local Denial of Service Vulnerability (CVE-2018-7995) Release date:Updated on:

Basic synchronization mechanism of the kernel:Key features of the preemption kernel: a process running in the kernel state that may be replaced by another process during kernel functions execution.Kernel preemption: Linux 2.6 Allows users to configure the kernel to be very e

/proc/kallsyms records the names and addresses of all the exported symbols in the kernel We need to compile 2 kernel modules, and then one of the kernel modules to call functions in another kernel module The HELLO.C code is as follows #include From this we can see that we have called 2 functions Add_integar and Sub

"copyright notice: respect for the original, reproduced please retain the source: blog.csdn.net/shallnet. The article is for academic communication only and should not be used for commercial purposes " the memory image of a process consists of the following parts: code snippet, data segment, BSS segmentand Stack segments. And the area of the memory map,memory-mapped function mmap (), which is responsible for mapping the contents of the file to the virtual memory space of the process, through rea

Differences between Linux 0.12 kernel and modern kernel in memory management Linux 0.12 kernel memory management is relatively simple and crude. The kernel only uses one page Directory and can only map 4 GB linear space. Therefore

The long and dark Prehistoric Age finally came to setup. In the setup Assembly function, Linux completes the transformation from prehistoric civilization to modern civilization by setting the PE bit of the Cr0 register (switching from the real mode to the protection mode. During the setup period, Linux has learned that the available memory resources in the world are far more than 1 MB. At this time, Linux's

Kernel synchronizationSynchronous introductionThe concept of synchronizationCritical section: Also known as a critical segment, is the code snippet that accesses and operates shared data.Competition conditions: 2 or more than 2 threads are executed simultaneously in the critical section, which constitutes a competitive condition.The so-called synchronization, in fact, prevent the formation of competitive conditions in the critical area.If the critical

In factCodeI have been analyzing it for a long time. I have long wanted to write something for myself. From today on, I will continue my blog! I have been dealing with Linux over the past few years, and I think I really fall in love with Linux. So write something about Linux! Linux has many things. As far as the

The Linux Kernel provides the copy_from_user ()/copy_to_user () function to copy the kernel state and user State data. However, these two functions cause blocking and cannot be used in hard or soft interruptions. These two special copy functions are generally used in functions similar to system calls. In the following code, the

when the Linux kernel is programmed, kernel code execution can only directly access the data in memory, and the file system on the hard disk must be indirectly read and written by the kernel. General kernel operation file read and write in three ways: 1. Through the/proc/fi

since you are dealing with kernel modules, it is natural to understand the dependencies between the modules provided by the kernel. Basically, the kernel module is placed at/lib/modules/$ (uname-r)/kernel, which is divided into several directories:Arch: Options related to the hardware platform, such as the CPU level.Cr

Unlike user-space applications, the kernel cannot invoke standard C libraries or any other libraries that are not part of the kernel. The main reason is the speed and size limits.The standard C library is too big for the kernel.Many of the commonly used LIBC functions have been implemented in the kernel. The library files in the

used locks to protect your data ), these non-atomic bitwise functions may execute faster than the atomic bitwise functions. 2. spin lock The most common lock in Linux kernel is spin lock ). A spin lock can only be held by one executable thread. If an execution thread tries to obtain a contention (held) spin lock, the thread will keep repeating-Rotating-waiting for the lock to be available again. S

complete_init (void) { int result; Result=register_chrdev (Complete_major,"complete", complete_fops); if (result return result; if (complete_major==0) Complete_major=result; return 0; } void Complete_cleanup (void) { Unregister_chrdev (Complete_major,"complete"); } Module_init (Complete_init); Module_exit (Complete_cleanup); Test steps:1, Mknod/dev/complete creates a complete node, and on Linux the driver needs to