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 5.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
- Rules on how to access information in sysfs
- Using the initial RAM disk (initrd)
- Control Group v2
- 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)
- ext4 General Information
- Power Management
- Thunderbolt
- Linux Security Module Usage
- Memory Management
- Perf Events and tool security
- ACPI Support
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
- Linux kernel licensing rules
- HOWTO do Linux kernel development
- Contributor Covenant Code of Conduct
- Linux Kernel Contributor Covenant Code of Conduct Interpretation
- A guide to the Kernel Development Process
- Submitting patches: the essential guide to getting your code into the kernel
- Programming Language
- 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
- 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
- Intel(R) Trace Hub (TH)
- System Trace Module
- MIPI SyS-T over STP
- 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
- CPU and Device Power Management
- The Common Clk Framework
- Bus-Independent Device Accesses
- Device connections
- Buffer Sharing and Synchronization
- Device links
- Component Helper for Aggregate Drivers
- Message-based devices
- Sound Devices
- Frame Buffer Library
- Voltage and current regulator API
- Industrial I/O
- Input Subsystem
- Linux USB API
- Firewire (IEEE 1394) driver Interface Guide
- The Linux PCI driver implementer’s API guide
- Serial Peripheral Interface (SPI)
- I2C and SMBus Subsystem
- I3C subsystem
- 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)
- 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
- General Purpose Input/Output (GPIO)
- Miscellaneous Devices
- DMAEngine documentation
- Linux kernel SLIMbus support
- SoundWire Documentation
- FPGA Subsystem
- ACPI Support
- Generic Counter Interface
- Core API Documentation
- Linux Media Subsystem Documentation
- Linux Networking Documentation
- netdev FAQ
- AF_XDP
- batman-adv
- SocketCAN - Controller Area Network
- The UCAN Protocol
- Vendor Device Drivers
- Distributed Switch Architecture
- Devlink info versions
- IEEE 802.15.4 Developer’s Guide
- Linux Networking and Network Devices APIs
- Z8530 Programming Guide
- MSG_ZEROCOPY
- FAILOVER
- NET_FAILOVER
- PHY Abstraction Layer
- phylink
- IP-Aliasing
- Ethernet Bridging
- SNMP counter
- Checksum Offloads
- Segmentation Offloads
- Scaling in the Linux Networking Stack
- Kernel TLS
- Kernel TLS offload
- The Linux Input Documentation
- Linux Hardware Monitoring
- Linux GPU Driver Developer’s Guide
- Security Documentation
- Linux Sound Subsystem Documentation
- Linux Kernel Crypto API
- Filesystems in the Linux kernel
- Linux Memory Management Documentation
- BPF Documentation
- Assorted Miscellaneous Devices Documentation
Architecture-specific documentation¶
These books provide programming details about architecture-specific implementation.
- x86-specific Documentation
- 1. The Linux/x86 Boot Protocol
- 2. x86 Topology
- 3. Kernel level exception handling
- 4. Kernel Stacks
- 5. Kernel Entries
- 6. Early Printk
- 7. ORC unwinder
- 8. Zero Page
- 9. The TLB
- 10. MTRR (Memory Type Range Register) control
- 11. PAT (Page Attribute Table)
- 12. Memory Protection Keys
- 13. Intel(R) Memory Protection Extensions (MPX)
- 14. AMD Memory Encryption
- 15. Page Table Isolation (PTI)
- 16. Microarchitectural Data Sampling (MDS) mitigation
- 17. The Linux Microcode Loader
- 18. User Interface for Resource Control feature
- 19. USB Legacy support
- 20. i386 Support
- 21. x86_64 Support
- SuperH Interfaces Guide
- x86-specific Documentation
- 1. The Linux/x86 Boot Protocol
- 2. x86 Topology
- 3. Kernel level exception handling
- 4. Kernel Stacks
- 5. Kernel Entries
- 6. Early Printk
- 7. ORC unwinder
- 8. Zero Page
- 9. The TLB
- 10. MTRR (Memory Type Range Register) control
- 11. PAT (Page Attribute Table)
- 12. Memory Protection Keys
- 13. Intel(R) Memory Protection Extensions (MPX)
- 14. AMD Memory Encryption
- 15. Page Table Isolation (PTI)
- 16. Microarchitectural Data Sampling (MDS) mitigation
- 17. The Linux Microcode Loader
- 18. User Interface for Resource Control feature
- 19. USB Legacy support
- 20. i386 Support
- 21. x86_64 Support
Filesystem Documentation¶
The documentation in this section are provided by specific filesystem subprojects.