liburing / IORING_OP_PROVIDE_BUFFERS - wrong buffer assigned to read op
I am playing with liburing and io_uring, the former is built from the master branch and for the latter i am using the kernel 5.8.0-rc3.I am facing the issue I am going to explain on previous version of...
View ArticleConfiguration of I2C bus over a switch in Linux
I have the following simplified schematic for my system. GPIO4+-----------------------------+ | GPIO3 | | +------------------------+ | | | GPIO2 | | | | +-------------------+ | | | | | GPIO1 | | | | |...
View Articlein Linux kernel, which function used process to get all inputs received from...
I want to monitor all incoming data received from networks but i want to use virtual memory introspection from Hypervisor level to put Breakpoints in common function used by network stack to intercept...
View ArticleEnlarge Linux Kernel Log Buffer more that 2M
I am in the process of collecting some sort of Linux Kernel activities. I have placed multiple printk statements with in the kernel source code and would like to monitor those during regular kernel...
View Articlewhat is the purpose of inet_ehash_insert() function
is inet_ehash_insert() responsable for adding the connection request to the syn queue of a socket in the TCP three-way-handshake in linux kernel. if no, which function does that ?PS: kernel 4.15
View ArticleReason why CFS scheduler using red black tree?
CFS scheduler picks next process based on minimum virtual time and to get this value efficiently its using Red-Black tree(rbtree), using rbtree we will get minimum O(h) here h is height of rbtree. But,...
View ArticleWhat is the theoretical maximum number of open TCP connections that a modern...
Assuming infinite performance from hardware, can a Linux box support >65536 open TCP connections?I understand that the number of ephemeral ports (<65536) limits the number of connections from one...
View ArticleUnreachable Instruction while compiling kernel on Virtual Machine
I've been trying to compile, build and install the latest stable version of the Linux kernel, 5.7.7.I first downloaded and unzipped the tar. Next, I ran cp /boot/config-$(uname -r) .config, followed by...
View ArticleHow to pull in the correct linux headers based on platform architecture?
I have a kernel module I'm building where I modified some protocols which changes socket.h, and I patched my running kernel with these changes. Then I test these sockets with a user-space program which...
View ArticleCompressing all files inside linux kernel rpm package
My current linux system has kernel-3.10.0-693.21.1.el7.x86_64 installed and now am trying to upgrade it to kernel-5.5.7 which is the latest stable release.Post compiling the tarball for kernel-5.7.7...
View ArticleWhy are the lightweight linux distros so light? [closed]
Linux distros like slax and puppy os have size around 200mbs and still come with a usable os that has a desktop environment and other softwares.But the barebones Arch Linux has a size of about 700...
View ArticleHow can I prevent SIGWINCH ignored from occurring?
I made a flask application and published it with gunicorn3 but one of my functions is not working properly. I also call one scripted screen and SIGWINCH ignored it. Gives the error gunicorn3. I called...
View ArticleHow to boot Linux kernel on Cortex m7 [closed]
I want to configure and boot the Linux kernel on a Cortex m7 microcontroller. In this case I'm using stm32H743 development board with on board DRAM. please guide me how to boot Linux on this board.I'm...
View ArticleIs there an easier way to share file descriptors between unrelated processes...
Does Linux provide a better way to send an fd from one process to another, for sharing, than using a sendmsg() syscall to send it (a message with type set to SCM_RIGHTS) over a UNIX Domain socket? I...
View ArticleHow can I prevent interrupts stepping out from my code while debugging?
I'm currently debugging the linux kernel and it's properly set up with kgdb.I set a breakpoint to a function I am trying to debug, and the break occurs once I run my program which needs this kernel...
View ArticleReusing Linux NUMA Subsystem for Customized UMA Memory Allocation
I have to isolate part of my DRAM (e.g., a rank) and allocate data,selectively, only from that portion. It seems that the NUMA subsystemwill be a suitable option. Am I right? Could somebody tell me...
View ArticleHow to get current process in Linux-4.9 (and above) through registers in X86_64?
Since Linux 4.9 in X86, kernel changed the kernel stack by putting thread_info into task_struct and put current process into per_cpu section.So it is NOT possible to get the current process in kernel...
View Articleafter compiling kernel which files are needed for kernel modules
I am compiling the Linux kernel for an embedded arm computer. I am using a CI system to run this compile for me. The size of the linux folder is 1.1G before compiling. After compiling it is 2.9G. I...
View ArticleHow to know which core that send the inter-processor interrupt?
I am working on ARM64. I add an inter-processor interrupt (IPI) handler in void handle_IPI(int ipinr, struct pt_regs *regs) in linux/arch/arm64/kernel/smp.c.When I get an IPI, I want to know which core...
View Articlehow to make i2c-core as module
Hello I have beagleboneblack board and have kernel source code I want to make my i2c work as a module so for that, I have done some changes in .config file## I2C support#CONFIG_I2C=mand cross compile...
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