Build and workflow
Which build workflow should I use, Yocto or standalone?
Use the Yocto workflow when you need a production-ready device image, want Yocto to manage the toolchain and sysroot, or are modifying kernel configuration fragments. Use the standalone workflow for rapid kernel iteration when you only need to rebuild and redeploy the kernel without rebuilding the full root file system. For a side-by-side comparison, see Get Started - Choose your workflow.How do I build only the kernel without rebuilding the full image?
Use the standalone workflow. It compiles the kernel independently of Yocto using a Docker-based cross-toolchain (kmake-image). The result is a UKI image that can be placed directly on the ESP partition. For setup and build steps, see Build the kernel standalone.
What kernel version does Qualcomm Linux use?
Qualcomm Linux tracks a Long-Term Support (LTS) kernel. The current version is v6.18.x. For the full version and compatibility table, see Supported versions and compatibility.Device tree and hardware
How do I find the correct DTB for my board?
DTB names follow the<SoC>-<board>-<variant>.dtb pattern. The KERNEL_DEVICETREE variable in the machine configuration file (meta-qcom/conf/machine/) shows which DTBs are built by default. For per-SoC DTB lists and device tree layout details, see Device tree architecture.
Logging and debugging
How do I increase or capture kernel log output?
Usedmesg for in-memory ring buffer access, or capture logs over the serial console. Log verbosity is controlled by the console log level. For serial console setup and log level configuration, see Kernel logging.
How do I connect a kernel debugger (KGDB)?
KGDB requires a serial connection between the target and the host running GDB. The kernel must be built withCONFIG_KGDB and CONFIG_KGDB_SERIAL_CONSOLE enabled. For the full setup procedure, see Kernel debugger (KGDB).
Kernel modules and subsystems
How do I add an out-of-tree kernel module?
Out-of-tree modules are built with the Yoctomodule class. A recipe inherits module, points to the driver source, and sets KERNEL_MODULE_AUTOLOAD to load the module on boot. For a complete recipe example, see Out-of-tree kernel modules.
How do I switch to the Real-Time kernel?
The RT kernel is a separate build configuration that enablesPREEMPT_RT. For build instructions, the switch procedure, and known limitations, see RT kernel fundamentals.