Difference between packages linux-headers-foo and linux-headers-foo-generic?

jhwilliams · 10-19-2009, 02:10 AM

Hi there,

Firstly, I don't really understand why Ubuntu uses the phrase "generic" on kernel packages. I'd always thought that -generic was a pseudonym or meta-pakcage for the base package. I just ran a diff on /usr/src/linux-headers-2.6.31-14 vs the -generic, and they're not the same. (Actually, I was expecting one to symlink the other.)

Code:

jameson@salmon:/usr/src$diff linux-headers-2.6.31-14 linux-headers-2.6.31-14-generic/
Common subdirectories: linux-headers-2.6.31-14/arch and linux-headers-2.6.31-14-generic/arch
Only in linux-headers-2.6.31-14-generic/: .config
Common subdirectories: linux-headers-2.6.31-14/include and linux-headers-2.6.31-14-generic/include
Common subdirectories: linux-headers-2.6.31-14/kernel and linux-headers-2.6.31-14-generic/kernel
Only in linux-headers-2.6.31-14-generic/: .missing-syscalls.d
Only in linux-headers-2.6.31-14-generic/: Module.symvers
Common subdirectories: linux-headers-2.6.31-14/scripts and linux-headers-2.6.31-14-generic/scripts
Only in linux-headers-2.6.31-14-generic/: source
Only in linux-headers-2.6.31-14-generic/: .tmp_versions
jameson@salmon:/usr/src$diff -r linux-headers-2.6.31-14 linux-headers-2.6.31-14-generic/
Only in linux-headers-2.6.31-14-generic/arch/x86/kernel: asm-offsets.s
Only in linux-headers-2.6.31-14-generic/arch/x86/kernel: .asm-offsets.s.cmd
Only in linux-headers-2.6.31-14-generic/: .config
Only in linux-headers-2.6.31-14-generic/include: asm
Only in linux-headers-2.6.31-14-generic/include: asm-x86
Only in linux-headers-2.6.31-14-generic/include: config
Only in linux-headers-2.6.31-14-generic/include/linux: autoconf.h
Only in linux-headers-2.6.31-14-generic/include/linux: bounds.h
Only in linux-headers-2.6.31-14-generic/include/linux: utsrelease.h
Only in linux-headers-2.6.31-14-generic/include/linux: version.h
Only in linux-headers-2.6.31-14-generic/kernel: bounds.s
Only in linux-headers-2.6.31-14-generic/kernel: .bounds.s.cmd
Only in linux-headers-2.6.31-14-generic/: .missing-syscalls.d
Only in linux-headers-2.6.31-14-generic/: Module.symvers
Only in linux-headers-2.6.31-14-generic/scripts/basic: docproc
Only in linux-headers-2.6.31-14-generic/scripts/basic: .docproc.cmd
Only in linux-headers-2.6.31-14-generic/scripts/basic: fixdep
Only in linux-headers-2.6.31-14-generic/scripts/basic: .fixdep.cmd
Only in linux-headers-2.6.31-14/scripts/basic: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts/basic: hash
Only in linux-headers-2.6.31-14-generic/scripts/basic: .hash.cmd
Only in linux-headers-2.6.31-14-generic/scripts: conmakehash
Only in linux-headers-2.6.31-14-generic/scripts: .conmakehash.cmd
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: genksyms
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: .genksyms.cmd
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: genksyms.o
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: .genksyms.o.cmd
Only in linux-headers-2.6.31-14/scripts/genksyms: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: keywords.c
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: lex.c
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: lex.o
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: .lex.o.cmd
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: parse.c
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: parse.h
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: parse.o
Only in linux-headers-2.6.31-14-generic/scripts/genksyms: .parse.o.cmd
Only in linux-headers-2.6.31-14/scripts: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts: kallsyms
Only in linux-headers-2.6.31-14-generic/scripts: .kallsyms.cmd
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: conf
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: .conf.cmd
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: conf.o
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: .conf.o.cmd
Only in linux-headers-2.6.31-14/scripts/kconfig: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: kxgettext.o
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: .kxgettext.o.cmd
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: lex.zconf.c
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: zconf.hash.c
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: zconf.tab.c
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: zconf.tab.o
Only in linux-headers-2.6.31-14-generic/scripts/kconfig: .zconf.tab.o.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: elfconfig.h
Only in linux-headers-2.6.31-14-generic/scripts/mod: .elfconfig.h.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: empty.o
Only in linux-headers-2.6.31-14-generic/scripts/mod: .empty.o.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: file2alias.o
Only in linux-headers-2.6.31-14-generic/scripts/mod: .file2alias.o.cmd
Only in linux-headers-2.6.31-14/scripts/mod: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts/mod: mk_elfconfig
Only in linux-headers-2.6.31-14-generic/scripts/mod: .mk_elfconfig.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: modpost
Only in linux-headers-2.6.31-14-generic/scripts/mod: .modpost.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: modpost.o
Only in linux-headers-2.6.31-14-generic/scripts/mod: .modpost.o.cmd
Only in linux-headers-2.6.31-14-generic/scripts/mod: sumversion.o
Only in linux-headers-2.6.31-14-generic/scripts/mod: .sumversion.o.cmd
Only in linux-headers-2.6.31-14/scripts/selinux/mdp: .gitignore
Only in linux-headers-2.6.31-14-generic/scripts/selinux/mdp: mdp
Only in linux-headers-2.6.31-14-generic/scripts/selinux/mdp: .mdp.cmd
Only in linux-headers-2.6.31-14-generic/: source
Only in linux-headers-2.6.31-14-generic/: .tmp_versions

What is this all about? What's the difference? What is a .cmd file?

rjlee · 10-19-2009, 05:04 AM

Generic is the name of one of the kernel images supplied with Ubuntu, and is optimised for the i686, and installed by default in the LiveCD and alternate CD. (http://hafizimtiaz.blogspot.com/2008...kernel-to.html)

The difference in the headers is that the -generic is preconfigured with the specific files for the i686 architecture, particularly the asm (assembly) files. Note that the kernel-headers are used to compile programs that need to know about the kernel's public interface, not to compile the kernel itself, so the kernel-headers packages have all these things set up by default.

I believe that the kernel-headers package contains just the vanilla kernel headers, since the -generic package depends on kernel-headers (see http://packages.ubuntu.com/intrepid-...6.27-7-generic), and the -generic one adds in extra files as needed.

Compiling your own kernel package: http://tuxicity.wordpress.com/2007/0...-architecture/

I'm not sure what a .cmd file is, but looking at the files, they seem to be something to do with the kernel's make/dependency system.