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Diffstat (limited to 'Documentation/kbuild/kbuild.rst')
| -rw-r--r-- | Documentation/kbuild/kbuild.rst | 58 |
1 files changed, 55 insertions, 3 deletions
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst index 08f575e6236c..82826b0332df 100644 --- a/Documentation/kbuild/kbuild.rst +++ b/Documentation/kbuild/kbuild.rst @@ -22,6 +22,11 @@ modules.builtin.modinfo This file contains modinfo from all modules that are built into the kernel. Unlike modinfo of a separate module, all fields are prefixed with module name. +modules.builtin.ranges +---------------------- +This file contains address offset ranges (per ELF section) for all modules +that are built into the kernel. Together with System.map, it can be used +to associate module names with symbols. Environment variables ===================== @@ -86,6 +91,17 @@ HOSTRUSTFLAGS ------------- Additional flags to be passed to $(HOSTRUSTC) when building host programs. +PROCMACROLDFLAGS +---------------- +Flags to be passed when linking Rust proc macros. Since proc macros are loaded +by rustc at build time, they must be linked in a way that is compatible with +the rustc toolchain being used. + +For instance, it can be useful when rustc uses a different C library than +the one the user wants to use for host programs. + +If unset, it defaults to the flags passed when linking host programs. + HOSTLDFLAGS ----------- Additional flags to be passed when linking host programs. @@ -129,10 +145,21 @@ KBUILD_OUTPUT ------------- Specify the output directory when building the kernel. +This variable can also be used to point to the kernel output directory when +building external modules against a pre-built kernel in a separate build +directory. Please note that this does NOT specify the output directory for the +external modules themselves. (Use KBUILD_EXTMOD_OUTPUT for that purpose.) + The output directory can also be specified using "O=...". Setting "O=..." takes precedence over KBUILD_OUTPUT. +KBUILD_EXTMOD_OUTPUT +-------------------- +Specify the output directory for external modules. + +Setting "MO=..." takes precedence over KBUILD_EXTMOD_OUTPUT. + KBUILD_EXTRA_WARN ----------------- Specify the extra build checks. The same value can be assigned by passing @@ -150,6 +177,12 @@ the UTS_MACHINE variable, and on some architectures also the kernel config. The value of KBUILD_DEBARCH is assumed (not checked) to be a valid Debian architecture. +KDOCFLAGS +--------- +Specify extra (warning/error) flags for kernel-doc checks during the build, +see scripts/kernel-doc for which flags are supported. Note that this doesn't +(currently) apply to documentation builds. + ARCH ---- Set ARCH to the architecture to be built. @@ -160,7 +193,7 @@ directory name found in the arch/ directory. But some architectures such as x86 and sparc have aliases. - x86: i386 for 32 bit, x86_64 for 64 bit -- sh: sh for 32 bit, sh64 for 64 bit +- parisc: parisc64 for 64 bit - sparc: sparc32 for 32 bit, sparc64 for 64 bit CROSS_COMPILE @@ -237,6 +270,12 @@ The output directory is often set using "O=..." on the commandline. The value can be overridden in which case the default value is ignored. +INSTALL_DTBS_PATH +----------------- +INSTALL_DTBS_PATH specifies where to install device tree blobs for +relocations required by build roots. This is not defined in the +makefile but the argument can be passed to make if needed. + KBUILD_ABS_SRCTREE -------------------------------------------------- Kbuild uses a relative path to point to the tree when possible. For instance, @@ -278,12 +317,25 @@ To get all available archs you can also specify all. E.g.:: $ make ALLSOURCE_ARCHS=all tags +IGNORE_DIRS +----------- +For tags/TAGS/cscope targets, you can choose which directories won't +be included in the databases, separated by blank space. E.g.:: + + $ make IGNORE_DIRS="drivers/gpu/drm/radeon tools" cscope + KBUILD_BUILD_TIMESTAMP ---------------------- Setting this to a date string overrides the timestamp used in the UTS_VERSION definition (uname -v in the running kernel). The value has to -be a string that can be passed to date -d. The default value -is the output of the date command at one point during build. +be a string that can be passed to date -d. E.g.:: + + $ KBUILD_BUILD_TIMESTAMP="Mon Oct 13 00:00:00 UTC 2025" make + +The default value is the output of the date command at one point during +build. If provided, this timestamp will also be used for mtime fields +within any initramfs archive. Initramfs mtimes are 32-bit, so dates before +the 1970 Unix epoch, or after 2106-02-07 06:28:15 UTC will fail. KBUILD_BUILD_USER, KBUILD_BUILD_HOST ------------------------------------ |