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Questions tagged [kernel-module]

A kernel module is a run-time loadable object file that is loaded into operating system kernel to add functionality to a running kernel. Examples include device drivers and other kernel items.

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Compile error: Kernel module

I am a newbie at kernel programming & I wish to run this kernel module (posted below)... and i ran the makefile (posted below) for that, but I am getting the following errors: Can someone please help me understand how to overcome this: The kernel…
Rookie
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Hello world kernel module for android & unknown relocation: 27 when insmod

I am trying to create a simple kernel module. I am trying to print messages to dmesg but i keep getting insmod: init_module 'hello.ko' failed (Exec format error) in android after : dmesg: unknown relocation: 27 #include #include…
raising hope
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Convert source IP address from struct iphdr* to string equivalent using Linux netfilter

I want to convert the source & destination IP addresses from a packet captured using netfilter to char *. In my netfilter hook function, I have: sock_buff = skb; // argument 2 of hook function // ip_header is struct iphdr* ip_header = (struct iphdr…
Jake
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human readable timestamp in linux kernel

How can I write human readable timestamp in linux kernel? I think do_gettimeofday returns epoch but I don't want to try to convert it to readable time. I just want a format like Hour:Min:Sec:Msec. Thanks
stedkka
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Why is my module unable to handle kernel paging request?

This is my module to allocate one huge page by using dequeue_huge_page_vma() and alloc_buddy_huge_page(). To make them vma independent, I get available vm area from __get_vm_area_node(), and then get its virtual address. I want to allocate one 2MB…
CindyRabbit
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How to write kernel space memory (physical address) to a file using O_DIRECT?

I want to write a physical memory to a file. The memory itself will not be touched again, thus I want to use O_DIRECT to gain the best write performance. My first idea was to open /dev/mem and mmap the memory and write everything to a file, which is…
Friedrich
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Profiling Linux Kernel Modules

I am interested in profiling a module for the Linux Kernel. I tried it this way: Built the kernel with CONFIG_PROFILING=y Booted the kernel with profile=2 Reset the profiler by echo 123 > /proc/profile The module was successfully loaded by a…
Albus Dumbledore
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How to find the version of a compiled kernel module?

I am in a situation where it would be very convenient to find the version of a loaded kernel module by querying the loaded module or .ko file. Is there a standard way to do this without digging into the source code?
Jacob Marble
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Linux kernel module crash debug: general protection fault: 0000 [#1] SMP

I have a kernel module for splitting incoming rtp packets and merging rtp outgoing packets. The program crashes once in 2/3 days. If would be very convenient for me if its possible to find the exact line where the module crashes. I have given the…
Habibullah Araphat Konok
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Not able to remove a loadable kernel module

I'm writing a loadable kernel module and trying to test it. After inserting it I was trying to remove it using rmmod xxx command, but I get an error saying module xxx is in use and the module gets stuck and I can't remove it. Any idea how to remove…
Varda Elentári
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Periodic task in a Linux kernel module

Currently I am developing GPIO kernel module for friendlyarm Linux 2.6.32.2 (mini2440). I am from electronics background and new to Linux. The kernel module loaded at start-up and the related device file is located in /dev as gpiofreq. At first time…
JD1910
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How to find physical and logical core number in a kernel module?

Are there kernel functions in Linux that would return the number of the physical core and logical core (in case of Hyperthreading) on which a kernel module is running ?
vjain27
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Warning: modules_install: missing 'System.map' file. Skipping depmod

I am trying to insert a kernel module using depmod and modprobe utilities in-order to resolve any dependencies. When I build the module it throws "Warning: modules_install: missing 'System.map' file. Skipping depmod." And later when I try to…
user11875340
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Is it possible to add a system call via a LKM?

I'd like to add a new system call via an LKM, but I'm not sure how to do this. That is, I know that if I want to add a completely new system call, I can look through the sys_call_table and find a sys_ni_syscall and just replace it, but I was curious…
FreeMemory
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Bluetooth over uart using hciattach?

I am using QN9021 SoC working in controller mode (BLE Bluetooth core specification v4.0). It supports some standard HCI commands as well as some vendor specific commands. I am trying to attach it in my ubuntu laptop. The command that i have used is…
abhiarora
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