kernel-module 相关问题

内核模块是一个运行时可加载的目标文件，它被加载到操作系统内核中以向正在运行的内核添加功能。示例包括设备驱动程序和其他内核项。

在内核模块中分配物理连续页我正在尝试使用alloc_pages_exact函数在DRAM中分配物理连续的页面。当我尝试分配10MB的页面时，返回的地址总是0。但是当我尝试分配...

static int __init hello_entry(void){ unsigned long i = 0; unsigned long j = 0; unsigned long counter; int fault = 0; char default_value = 0xff; unsigned long size_of_memory_to_test_bytes = 10 * 1024 * 1024;//10MB chunk unsigned long page_size = 8 * 1024;//8kB page size. From data sheet for elpida 4GB ddr3 ram unsigned long number_of_pages = size_of_memory_to_test_bytes / page_size; unsigned long number_of_hammer_access = 200000; printk("Number Of Bytes to allocate: %ld\n", number_of_pages * page_size); char* pages = (char *)alloc_pages_exact(number_of_pages * page_size, GFP_KERNEL); while(pages == 0);//The Program must wait till enough pages have been allocated! printk("Starting Address: %x", pages); char *hammerRow0, *hammerRow1, *victimRow; char hammerRow0_data, victimRow_data, hammerRow1_data, read_midvalue; printk(KERN_ALERT "Memory Test Entry!\n"); printk(KERN_ALERT "Page Size: %ld\n", page_size); printk(KERN_ALERT "Cache Line Size: %d\n", cache_line_size()); //The design consists of two hammer rows which will be repeatedly accessed one after another //There will be a victim row in between the two hammer rows, kind of like a victim row sandwiched between two hammer rows //This will server two purposes: //1. Greater probability of inducing bitflip in the victim row due to repeated access of two adjacent rows. //2. Clearing out the row buffer of DRAM chip so that it is guaranteed that the wordline will be accessed to access the data printk(KERN_INFO "Rowhammer Test Starts\n"); for(counter = 0; counter < number_of_pages - 2; counter++){ //Doing the rowhammer test on every page of dram hammerRow0 = pages + counter; victimRow = hammerRow0 + page_size; hammerRow1 = victimRow + page_size; //Storing initial data into rows to check them later for errors for(i = 0; i < page_size / sizeof(char); i++){ //Setting all bits of dram 1 to maximize the possibility of charge leak hammerRow0[i] = default_value; victimRow[i] = default_value; hammerRow1[i] = default_value; } //Starting Hammer Test //printk(KERN_INFO "Rowhammer Test Starts\n"); fault = 0; for(j = 0; j < number_of_hammer_access; j++){ //hammerRow0 access //This is an x86 specific funnction that executes CLFLUSH. Mre info on CLFLUSh: https://c9x.me/x86/html/file_module_x86_id_30.html clflush_cache_range(hammerRow0, sizeof(char)); read_midvalue = hammerRow0[0]; //Reading the first value present in the page //hammerRow1 access clflush_cache_range(hammerRow1, sizeof(int)); read_midvalue = hammerRow1[0]; //Reading the first value present in the page } //Checking the victim row for errors for(i = 0; i < page_size / sizeof(int); i++){ victimRow_data = victimRow[i]; if(victimRow_data != default_value){ printk(KERN_ALERT "victimRow Fault (After Hammering) at index %d: Present Value: %x \t Expected Value: %x:\tRow numer %d\n", i, victimRow_data, 0xff, counter); fault = 1; } } if(fault == 1){ printk(KERN_ALERT "Rowhammer Test Failed\n"); return 0; } else { //printk(KERN_ALERT "Rowhammer Test Passed for Row %d\n", counter); } } printk(KERN_ALERT "Rowhammer Test Passed\n"); return 0; } static void __exit hello_exit(void){ printk(KERN_INFO "Memory Test Exit!\n"); } module_init(hello_entry); module_exit(hello_exit); //Licensing Info MODULE_LICENSE("GPL"); MODULE_AUTHOR("jonvonton"); MODULE_DESCRIPTION("Rowhammer Testing");

c linux memory-management linux-kernel kernel-module

回答 1 投票 0

如何自动加载/卸载Linux设备驱动程序？

linux linux-kernel linux-device-driver kernel-module

回答 1 投票 0

在内核中进行io_uring提交我需要一个快速的异步频道将数据从我的内核模块传输到用户空间应用程序。我尝试了io_uring。就我而言，在内核中处理其提交的方式是黑匣子，...

使用特定的chardev来确保他创建的模块会收到提交。那是简单的部分。困难的部分是那里存在的

kernel-module io-uring

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使用保留记忆并了解memremap（）函数

我尝试在保留的内存区域实现自己的Linux驱动程序。我在此描述中遵循：https：//xilinx-wiki.atlassian.net/wiki/wiki/spaces/a/pages/18841683/linux+reserved+reserved+memory 内存

linux-kernel embedded-linux kernel-module memory-mapping