Linux kernel filp_open fails with NOENT
I currently work on a kernel module where I deal with user-space files. I know it is considered a bad practice and all, but I still need.The module places an hook using netfilter to catch every...
View ArticleKernel access and stopping process before start
I want to catch processes in python before they started. I tried to catch them via listening processtree but it need too much cpu. How can i catch processes before they start. I'm trying to catch...
View Articlekernel 4.4.192 spinlock already unlocked
during normal usage, system locked up, and the following messages appeared on the screen. where you can see from the log, the spinlock owner and CPU are -1. After this BUG the system restarts by...
View Articlewhy this built-in kernel module's init function won't be called on startup?
I'm using Linux on an MMU-less ARM platform, so, normal ELF files won't work and I should use FDPIC_ELF executable. but my kernel couldn't execute fdpic executables (error -8 (ENOEXEC)).so, I decided...
View ArticleHow can I disable producing paged (non-linear) skb's in Linux kernel?
Suppose I write some LKM with networking (netfilter) activity and I need to do some tampering with skb including skb_pull(). So I have to take care about is skb linear or not before pulling.If I...
View ArticleUnpack/repack dtb.img file
Hello,I have a question for unpack/repack existing dtb.img file in Linux for Android kernel Exynos 9820 platform.I've tried some stuff like mkbootimg, dtbtool without success - or I don't know how or...
View ArticleCan't update to WSL 2 [closed]
I am continuously receiving this error while I am trying to switch from WSL 1 to WSl 2.How shall I get updated?Conversion in progress, this may take a few minutes...For information on key differences...
View ArticleNetwork Output Buffering
How can I hold the packets generated from a server until an external signal is delievered. On receiving the signal the host hosting the server should release the packets?I think it can be done with...
View ArticleBluetooth still appears on boot list after "disabling" on defconfig on a...
I edit my defconfig on /build/tmp/work/imx6qciu-poky-linux-gnueabi/linux/3.10.53-r0/git/arch/arm/configs with a patch to set...
View Articlemmap more than one buffer in kernel is crashing please help (using...
I'm developing a Linux kernel module that allocates more than one buffer per char device and then the user-space application maps those buffers to the user-space. My character device class has around...
View ArticleVim Parrot Os not installing
Hello guys I've been trying to install vim on my parrot Os but each and every time I encounter the same error. I've tried upgrading, updating and still i encounter the very same problem here is the...
View ArticleHow to setup a periodic timer callback in a Linux kernel module
I am working on a Linux kernel module that registers a callback for interrupts that come from a custom-made board and puts the received data in a queue behind a char device interface to be processed by...
View ArticleChange linux kernel timer
I have to run a latency sensitive application and I have been asked to change the timer resolution to 1000 Hz or more. I searched on the net a bit and found pages about CONFIG_HZ etc.However, there are...
View ArticleWhat is the difference between vmalloc and kmalloc?
I've googled around and found most people advocating the use of kmalloc, as you're guaranteed to get contiguous physical blocks of memory. However, it also seems as though kmalloc can fail if a...
View Articlehow to compile a C program as FDPIC_ELF without using Shared Libs
my platform:Host: | OS: Ubuntu 20 LTS | Kernel: Microsoft WSL2 Linux Kernel | Cross compile Toolchain: arm-linux-gnueabi-gcc |__Target: | Board: Waveshare CoreH7XXI | SOC: stm32h743 (Single Core Cortex...
View Articleadd-symbol-file returns -s invalid argument when trying to add module's...
I'm debugging vmlinux with gdb vmlinux /proc/kcore, and I want to add a symbol file, I installed a module and then check the location of .bss, .data and .init in /sys/module/simple_module/sections....
View ArticleData corruption when memcpy from DMA
EDIT:A bit more info have been added to the Debugging section.==========================================================================I'm having issues with data corruption in an Ethernet driver (for...
View ArticlePostgres under Docker getting OOM kill from host
I have VM with 8GB of memory (Terraformed), on which there are 2 Docker containers:a minimal metrics exporter, of 32MBa Bitnami Postgres12 container with my database.The data has been fully loaded,...
View ArticleLinux kernel per-cpu variable area's starting address and size
At a high-level I understand that when you create a per-CPU variable, each processor on the system gets its own copy of that variable. Some implementation details are here. I still have few things...
View ArticleNetwork-packets buffering in kernel qdiscs module
I want to buffer output packets originating from a container's network interface.This netlink library file named sch_plug.c https://code.woboq.org/linux/linux/net/sched/sch_plug.c.html looks like it...
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