Freaks City

Memory Layout and Page Table Management Hardware Device Mapping Hardware devices like UART0 (0x10000000L), VIRTIO0, CLINT, and PLIC have fixed physical addresses and interrupt numbers defined by hardware design. The kernel uses these addresses to communicate with devices, initialize registers, and handle interrupts. Kernel Loading and Execution ...

Process Concealment via Procfs Mounting In Linux environments, process metadata is exposed via the /proc pseudo-filesystem. Standard monitoring utilities like ps, top, and htop retrieve system information by reading the subdirectories within /proc that correspond to specific Process IDs (PIDs). By utilizing the mount command with the --bind fla ...

The Input/Output Memory Management Unit (IOMMU) is a hardware component that enables memory protection and address translation for Direct Memory Access (DMA) operations initiated by peripheral devices. By enforcing isolation between devices and system memory, the IOMMU enhances both security and performance. In Linux, IOMMU groups represent the ...

Modern operating system kernels rely fundamentally on interrupt-driven execution. Interrupts enable asynchronous event handling—such as hardware signals, exceptions, and system calls—without requiring constant polling or blocking waits. Interrupt Classification External Interrupts Maskable interrupts arrive via the INTR pin and can be disabled ...

SPI Core Concepts SPI (Serial Peripheral Interface) is a synchronous, full-duplex serial communication protocol originally developed by Motorola. It enables MCUs or MPUs to exchange data with peripherals such as flash memory, ADCs, network controllers, or other processors. Key attributes include high-speed operation, serial data transfer, and t ...