Migrating to the common kernel-image package -------------------------------------------- Files for architecture should be placed into arch/. Minimally, this directory should contain a control.in, config.default and at least one flavour configuration file config.. It can optionally contain config, Makefile.inc and multiple flavour configuration files. For arches with subarches the subdirectory arch// with the same file structure must be created for each subarch. Support for arch/subarch-specific patches ----------------------------------------- Patches specific to a particular architecture or subarchitecture and not included into the debian patch set should be placed in the debian/patches-arch subdirectory. Patch must be named .diff or .diff. If such patch is present, it will be automatically applied during the unpacking of the build tree for a particular (sub)architecture. Patches present in the debian/patches-arch will also be included in the kernel-patch-debian package, suitable for building kernels with make-kpkg. Config files ------------ Configuration files are constructed dynamically by concatenating a number of config files as described below. Any of the files, except the .default and lowest-level . files, may be missing. For architecture without subarches: Configuration file for kernel-image: arch/config arch//config arch//config. Configuration file for kernel-headers: arch//config.default For architecture with subarches: arch/config arch//config arch///config arch///config. Configuration file for kernel-headers: arch///config.default Control file ------------ The master control file debian/control must be generated before the package is uploaded. debian/rules contains the debian/control target, which generates the control file by concatenating the common templates for it and substituting the variables: @version@ Upstream kernel version, for example 2.6.11. @major@ The major version, for example 2.6 @arch@ The Debian arch name, such as powerpc or i386. @subarch@ The subarch - only used by powerpc right now. @flavour@ The build flavour, such as 686 or k7-smp. @smpflavour@ Same as flavour, but turns k7-smp into "multiprocessor k7". @shortsmpflavour@ Same as smpflavour, but turns k7-smp into "SMP k7". @ltver@ linux-tree version, a single digit. @srcver@ Source version, extracted from the changelog. This is normally @version@-@ltver@. @lt_depends@ The Depends field for the linux-tree package. @lt_provides@ The Provides field for the linux-tree package. @abiname@ Current abiname, a single digit. @allheaders@ Given the arch, a list of all the linux-headers packages for the arch - used for kernel-headers-x.y.z-n-arch. For each kernel image build the control.source.in template from templates directory is concatenated with the control.in file from the arch/ or arch// directory, and the following variables are substituted: @version@, @ltver@, @major@, @abiname@. A arch/subarch-specific control.in file should contain only entries for binary linux-image-$(version)-$(abiname)-$(flavour) and flavour-specific linux-headers-$(version)-$(abiname)-$(flavour) packages. linux-headers-$(version)-$(abiname) package entry is included automatically. After variable substitution the resulting files are formatted to ensure that the only blank lines are the ones separating the entries (i.e. before the next Package: line). Makefile.inc ------------ Each architecture subdirectory in arch may contain a Makefile.inc file, which is included by debian/rules after definining all the variables. It may be used to override the standard variables on per-architecture basis and other evil things. So far the valid uses of this file include the setting of the following variables: headers_dirs This variable is substituted into the headers-install script, controlling which asm-* directories are included into the kernel-headers package. By default it is set to karch (see above). See header-install.in file for detail. Typical usage: headers_dirs := sparc | sparc64 headers_extra This variable is substituted into the headers-install script, and may be used to specify extra files, which a particular architecture would like to include in the kernel-headers package. Files should be specified with a full path relative to the top-level kernel directory, unquoted and separated by spaces. Note that you normally do not need to specify the files arch/$(karch)/kernel/asm-offsets.s, they are going to be included automatically. headers_subarch The subarch to pass to the --subarch option for the make-kpkg call to build the kernel-headers. Typical usage: headers_subarch := sparc64 build_subarch Setting this variable to non-empty value will cause an option --subarch $(build_subarch) added to 'build' and 'kernel-image' make-kpkg calls. If a substring @flavour@ is present in the definition of this variable, it will be expanded to the current flavour during build time. In general, if you wish to add subarch support for your architecture, you should contact kernel-package maintainer to ensure that the flavour name correctly maps onto a kernel subarch name. Typical usage: build_subarch := pmac or build_subarch := @flavour@ build_makeflags This variable may contain the make flags settings for the make-kpkg invocation in the 'build' target. Currently it is only used by amd64, where it should be set to something like build_makeflags := 'CC=amd64-linux-gcc V=1' The value of the variable must be properly quoted. initrd_modules This variable may contain a space-separated list of modules which should be hard-linked into the /lib/modules//initrd directory, so that they will be included by mkinitrd. Full pathname relative to the /lib/modules/ directory should be give, no quoting is necessary. Typical usage: initrd_modules := kernel/drivers/video/vesafb.ko kernel/security/capability.ko image_postproc A command to be run after the kernel image is built. As far as I know, it only required on sparc for stripping of the kernel which is too big to be booted otherwise. Typical use is too ugly to be presented here. image_prefix_flavours image_prefix These variables allow to prepend the 'make-kpkg kernel_image' call with an arbitrary prefix for selected flavours. Some architectures have a 32- and 64-bit versions. If kernels are built on the 64-bit hardware, then building a 32-bit kernel usually requires using a wrapper which sets the correct execution domain (such as sparc32 or linux32). If the variable image_prefix_flavours is non-empty and contains a space-separated list if flavours, then make-kpkg invocation to create a kernel_image target will be prepended with contents of the image_prefix variable. Typical usage: image_prefix_flavours := sparc32 sparc32-smp image_prefix := sparc32 default_config This variable controls which kernel config file will be used as a "default" config file, used when building the kernel-headers package. It does not really matter which file is used, see the message at http://lists.debian.org/debian-kernel/2004/08/msg01460.html The following algorithm will be used to determine the default kernel config file: * If the default_config variable is defined, use config.$(default_config). * If it is not defined and config.default exists, use that. * If neither default_config is defined not config.default exists, pick the first flavour from the flavour list and use its config. Typical usage: default_config := 386 extra_postinstall_command This variable, if defined, is executed at the end of the post-install script, which is used by kernel-package to add or modify the files going into the kernel image package. It can use these variables (but see templates/post-install.in for details) : $(subarch), $(flavour), $(version) and $(abiname). Since Makefile.inc is a Makefile, the leading $ need to be escaped as double $$.