The Linux Kernel documentation¶
This is the top level of the kernel’s documentation tree. Kernel documentation, like the kernel itself, is very much a work in progress; that is especially true as we work to integrate our many scattered documents into a coherent whole. Please note that improvements to the documentation are welcome; join the linux-doc list at vger.kernel.org if you want to help out.
Licensing documentation¶
The following describes the license of the Linux kernel source code (GPLv2), how to properly mark the license of individual files in the source tree, as well as links to the full license text.
User-oriented documentation¶
The following manuals are written for users of the kernel — those who are trying to get it to work optimally on a given system.
- The Linux kernel user’s and administrator’s guide
- Linux kernel release 4.x <http://kernel.org/>
- The kernel’s command-line parameters
- Linux allocated devices (4.x+ version)
- Hardware vulnerabilities
- Reporting bugs
- Security bugs
- Bug hunting
- Bisecting a bug
- Tainted kernels
- Ramoops oops/panic logger
- Dynamic debug
- Explaining the dreaded “No init found.” boot hang message
- Documentation for Kdump - The kexec-based Crash Dumping Solution
- Rules on how to access information in sysfs
- Using the initial RAM disk (initrd)
- Control Group v2
- Device Mapper
- Linux Serial Console
- Linux Braille Console
- Parport
- RAID arrays
- Kernel module signing facility
- Linux Magic System Request Key Hacks
- Unicode support
- Software cursor for VGA
- Kernel Support for miscellaneous (your favourite) Binary Formats v1.1
- Mono(tm) Binary Kernel Support for Linux
- Java(tm) Binary Kernel Support for Linux v1.03
- Reliability, Availability and Serviceability
- A block layer cache (bcache)
- Power Management
- USB4 and Thunderbolt
- Linux Security Module Usage
- Memory Management
Application-developer documentation¶
The user-space API manual gathers together documents describing aspects of the kernel interface as seen by application developers.
Introduction to kernel development¶
These manuals contain overall information about how to develop the kernel. The kernel community is quite large, with thousands of developers contributing over the course of a year. As with any large community, knowing how things are done will make the process of getting your changes merged much easier.
- Working with the kernel development community
- HOWTO do Linux kernel development
- Code of Conflict
- A guide to the Kernel Development Process
- Submitting patches: the essential guide to getting your code into the kernel
- Linux kernel coding style
- Kernel Maintainer PGP guide
- Email clients info for Linux
- Linux Kernel Enforcement Statement
- Kernel Driver Statement
- Minimal requirements to compile the Kernel
- Submitting Drivers For The Linux Kernel
- The Linux Kernel Driver Interface
- Linux kernel management style
- Everything you ever wanted to know about Linux -stable releases
- Linux Kernel patch submission checklist
- Index of Documentation for People Interested in Writing and/or Understanding the Linux Kernel
- Deprecated Interfaces, Language Features, Attributes, and Conventions
- Applying Patches To The Linux Kernel
- Adding a New System Call
- Linux magic numbers
- Why the “volatile” type class should not be used
- clang-format
- Development tools for the kernel
- Kernel Testing Guide
- Coccinelle
- Sparse
- kcov: code coverage for fuzzing
- Using gcov with the Linux kernel
- The Kernel Address Sanitizer (KASAN)
- The Undefined Behavior Sanitizer - UBSAN
- Kernel Memory Leak Detector
- Debugging kernel and modules via gdb
- Using kgdb, kdb and the kernel debugger internals
- Linux Kernel Selftests
- KUnit - Linux Kernel Unit Testing
- How to write kernel documentation
- Kernel Hacking Guides
- Linux Tracing Technologies
- Function Tracer Design
- Notes on Analysing Behaviour Using Events and Tracepoints
- ftrace - Function Tracer
- Using ftrace to hook to functions
- Kprobe-based Event Tracing
- Uprobe-tracer: Uprobe-based Event Tracing
- Using the Linux Kernel Tracepoints
- Event Tracing
- Subsystem Trace Points: kmem
- Subsystem Trace Points: power
- NMI Trace Events
- MSR Trace Events
- In-kernel memory-mapped I/O tracing
- Event Histograms
- Hardware Latency Detector
- OSNOISE Tracer
- Timerlat tracer
- Intel(R) Trace Hub (TH)
- System Trace Module
- Kernel Maintainer Handbook
Kernel API documentation¶
These books get into the details of how specific kernel subsystems work from the point of view of a kernel developer. Much of the information here is taken directly from the kernel source, with supplemental material added as needed (or at least as we managed to add it — probably not all that is needed).
- The Linux driver implementer’s API guide
- Driver Basics
- Device drivers infrastructure
- Device Power Management
- The Common Clk Framework
- Bus-Independent Device Accesses
- Buffer Sharing and Synchronization
- Device links
- Component Helper for Aggregate Drivers
- Message-based devices
- Sound Devices
- Managing Ownership of the Framebuffer Aperture
- Frame Buffer Library
- Voltage and current regulator API
- Industrial I/O
- Input Subsystem
- Linux USB API
- The Linux PCI driver implementer’s API guide
- Serial Peripheral Interface (SPI)
- I2C and SMBus Subsystem
- IPMB Driver for a Satellite MC
- The Linux IPMI Driver
- High Speed Synchronous Serial Interface (HSI)
- Error Detection And Correction (EDAC) Devices
- SCSI Interfaces Guide
- libATA Developer’s Guide
- target and iSCSI Interfaces Guide
- MTD NAND Driver Programming Interface
- Parallel Port Devices
- 16x50 UART Driver
- Pulse-Width Modulation (PWM)
- Intel(R) Management Engine Interface (Intel(R) MEI)
- W1: Dallas’ 1-wire bus
- RapidIO Subsystem Guide
- Writing s390 channel device drivers
- VME Device Drivers
- Linux 802.11 Driver Developer’s Guide
- The Userspace I/O HOWTO
- Linux Firmware API
- PINCTRL (PIN CONTROL) subsystem
- PLDM Firmware Flash Update Library
- Overview of the
pldmfw
library - General Purpose Input/Output (GPIO)
- Miscellaneous Devices
- DMAEngine documentation
- Linux kernel SLIMbus support
- SoundWire Documentation
- FPGA Subsystem
- Auxiliary Bus
- Support for Serial devices
- Core API Documentation
- InfiniBand
- Linux Media Subsystem Documentation
- Linux Networking Documentation
- AF_XDP
- Bare UDP Tunnelling Module Documentation
- batman-adv
- SocketCAN - Controller Area Network
- The UCAN Protocol
- DPAA2 Documentation
- Linux* Base Driver for the Intel(R) PRO/100 Family of Adapters
- Linux* Base Driver for Intel(R) Ethernet Network Connection
- Linux kernel driver for Compute Engine Virtual Ethernet (gve):
- Netlink interface for ethtool
- Linux Networking and Network Devices APIs
- Z8530 Programming Guide
- MSG_ZEROCOPY
- PHY Abstraction Layer
- phylink
- Ethernet Bridging
- Kernel TLS
- Kernel TLS offload
- Linux Socket Filtering aka Berkeley Packet Filter (BPF)
- MPTCP Sysfs variables
- SMC Sysctl
- Interface statistics
- Ethernet switch device driver model (switchdev)
- TC queue based filtering
- Linux Kernel TIPC
- Virtual eXtensible Local Area Networking documentation
- The Linux Input Documentation
- Linux GPU Driver Developer’s Guide
- Security Documentation
- Linux Sound Subsystem Documentation
- Linux Kernel Crypto API
- Linux Filesystems API
- Linux Memory Management Documentation
- BPF Documentation
- Linux PCI Bus Subsystem
- 1. How To Write Linux PCI Drivers
- 2. The PCI Express Port Bus Driver Guide HOWTO
- 3. PCI Express I/O Virtualization Howto
- 4. The MSI Driver Guide HOWTO
- 5. ACPI considerations for PCI host bridges
- 6. PCI Error Recovery
- 7. The PCI Express Advanced Error Reporting Driver Guide HOWTO
- 8. PCI Endpoint Framework
- 9. Boot Interrupts
Architecture-agnostic documentation¶
Architecture-specific documentation¶
These books provide programming details about architecture-specific implementation.
- SuperH Interfaces Guide
- x86 architecture specifics
- Intel Trust Domain Extensions (TDX)
- Microarchitectural Data Sampling (MDS) mitigation
- User Interface for Resource Control feature
- TSX Async Abort (TAA) mitigation
- Bus lock detection and handling
- Software Guard eXtensions (SGX)
- Shared Virtual Addressing (SVA) with ENQCMD
- x86-specific ELF Auxiliary Vectors
- Using XSTATE features in user space applications
- Hardware-Feedback Interface for scheduling on Intel Hardware
- In-Field Scan