Skip to content

Tag: linux-kernel

How to include device tree overlay into Raspberry Pi CM4

I would like to include UART3 and UART5 overlay to enable them, using Yocto. They are already delivered with the whole package ( I added to my main image recipe lines: I have also added .bbappend to enable them in /boot/config.txt (file /meta-mylayer/recipes-bsp/bootfiles/rpi-config_%.bbappend): And I receive an error: I suppose that those overlays are not compiled, how can I include

How does the bitwise AND help in the if statements in the Linux Kernel?

Background on what the code is trying to achieve: “Various parameters of the new process (e.g., euid, egid, argument list, environment, filename, etc.) that are subsequently passed to other functions are, for the sake of simplicity, combined into a structure of type linux_binprm. prepare_binprm is used to supply a number of parent process values (above all, the effective UID and

Changing process priorities

Building off of this, I would like to change process priorities based on RAM usage. I’m perfectly aware that this isn’t always the best way to change priorities, but this is just for a project. I’m trying to use renice and execvp to set process priorities. The problem is that I want to launch renice with additional parameters to change

Is there a different memory allocation path other than the buddy allocator in linux?

I’m understanding memory allocation in Linux and doing some changes in buddy allocator (__alloc_pages_nodemask) for my experiments. I create a new flag in struct page->flags (by adding a new flag in enum pageflags in page-flags.h. I set this bit permanently in __alloc_pages_nodemask (to not to be cleared once set and survive all further allocation and freeing. I modify PAGE_FLAGS_CHECK_AT_PREP to