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Creating New Folder in Linux [closed]
How can I add new folder in linux? I checked the permission but the Owner is mentioned as "root" and I can't change it. Don't know what to do and how?I tried to get the authorization using terminal by...
View ArticlePCI error handler in kernel driver never called, even when device is turned off
I'm writing a linux kernel device driver for a custom PCIe device. A user space application is mmapped to this device and frequently accessing its memory (read and write). The PCIe device is driven by...
View ArticleCan't see kernel symbols in 'perf report' when trying to trace a probe on...
I'm trying to see what kernel code calls a specific function on CentOS 7.7 (x86-64). I've tried this:perf probe -a vsnprintf perf record -e probe:vsnprintf -aR sleep 10 Then, when I try:perf report...
View Articlehow to map a certain kernel space to different virtual machine?
I am doing something like "shared memory", I want to map the virtual address in KVM to the same PFN so that I can share information between virtual machines. However I encounter some problems.the...
View ArticleLKM: System freeze upon using insmod
I'm new in kernel development. I'm trying to see if I can make a call to a function from the __init section. But after building the module, when I use insmod XXX.ko to insert my module, my system does...
View Articlecrypto_akcipher_set_pub_key in kernel asymmetric crypto always returns error
I'm working on a kernel module which uses asymmetric cipher of kernel crypto api, kernel version 4.8.0. I generate asymmetric key pairs by openssl, convert them into DER format (which I knew was a...
View Articlewhich function that linux kernel use to kick start the scheduler
Hi I am studying the Linux kernel source code, and am trying to understand how Linux kernel scheduler works, the question I have is: Is there a function in linux kernel for the kernel to kick start the...
View ArticleObtaining real device of VLAN-interface through the netlink
I need to obtain the real_dev (f.e. ID) of the given VLAN-inteface.I wrote some test snippet using libnl:int main(void) { struct nl_sock *sock; struct nl_cache *cache; char iface[] = "eno1.10"; //char...
View ArticleI couldn't boot the Linux kernel with my new U-Boot environment variable
Use the following command to start the kernel:setenv bootnet 'tftp 80800000 zImage;tftp 83000000 xxx.dtb' saveenv run bootnet bootz 80800000 - 83000000 But using the following command will stop at the...
View ArticleAndroid Dalvik scheduler linux kernel question
Dalvik VM can run several independent processes that are managed by the linux kernel and are executed according to priority, but kerel uses CFS (completely fair scheduler). can the scheduler be changed...
View ArticleRead from /proc/$PID/smaps is slow
We need to monitor memory usage of our high-loaded service every minute by cron.For this we are reading /proc/PID/smaps and somehow parse it.But we are encountering timing problems exactly every...
View ArticleThere's problem if remove one kernel from centos 7
have problem with install Symantec agent in amzn2 ec2 , need to remove the kernel version kernel-4.14.152-127.182.amzn2.x86_64 , there's problem if delete it
View ArticleUsing float, double arithmeetic causes warnings on arm
I have a device driver which was compiling fine using arm-linux-gnueabi- I added a few double and float operations into the code and I have been getting the following warnings at compilation:WARNING:...
View ArticleYocto device-tree interrupt on certain pin
I am working on a custom .dts file for my beaglebone cape. I've successfully created a bsp-layer and custom image, everythin is working fine. Now i want to make changes in a device-tree to assign...
View ArticleWhen VmallocUsed in /proc/meminfo will increase
I see the following fields in /proc/meminfo related to vmalloc.VmallocTotal: 34359738367 kB VmallocUsed: 0 kB VmallocChunk: 0 kB So, i wrote a basic kernel module which allocates memory using vmalloc...
View ArticleHow can I tell the compiler/CPU to execute instructions back to back in...
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?For example I'd like the kernel module to execute write (or...
View ArticleHow beaglbone black linux is booted?
I am trying to make my own image for beaglbone black and I am a bit lost in boot process. I understand the sequence: ROM bootloader -> MLO -> u-boot -> kernel. However going from theory to...
View ArticleExtending Kaldi Aspire: bad variable error while Recompiling HCLG.fst using...
I have successfully setup and run the Kaldi Aspire recipe on my WSL. Now i was working on a POC where i want to extend the ASPIRE recipe by making a new corpus, dictionary, language model and merge it...
View ArticleForwarding packets from NIC to WiFi using raw sockets in kernel space
For a project, I have 2 laptops with 2 wireless interfaces (wlan0 and wlan1) and one NIC, let's call the laptops Sender and Receiver. What I would like to do is to send the odd packets that arrive to...
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How to use the kernel hash table?
I'm trying to understand and use the kernel hash tables and I've already read this and this link, but I didn't understand none of them. My first question is: Why our struct has to have the struct...
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