Re: [PATCH REBASE] Add option to disable kernel compression

[Andrew Morton <akpm@linux-foundation.org>]

On Tue,  8 Oct 2013 14:33:32 +0200 Christian Ruppert <christian.ruppert@abilis.com> wrote:

> Until now, kernel compression can only be disabled by deselecting
> HAVE_<compression> in the architecture Kconfig.

Scratching my head a bit.  There's no way of deselecting these things. 
I *think* you mean "by editing arch/xxx/Kconfig and removing all the
"select HAVE_KERNEL_<compression>" lines"?

> However, some
> users/platforms within the same architecture might want to use
> compression while others might want to disable it.

Why would anyone want to run an uncompressed kernel, btw?  Boot time?

> This patch is a solution to the dilemma.
> 
> ...
>
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -118,7 +118,6 @@ config HAVE_KERNEL_LZ4
>  choice
>  	prompt "Kernel compression mode"
>  	default KERNEL_GZIP
> -	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4
>  	help
>  	  The linux kernel is a kind of self-extracting executable.
>  	  Several compression algorithms are available, which differ
> @@ -137,6 +136,13 @@ choice
>  
>  	  If in doubt, select 'gzip'
>  
> +config KERNEL_UNCOMPRESSED
> +	bool "No compression"
> +	help
> +	  No compression at all. The kernel is huge but the compression and
> +	  decompression times are zero.
> +	  This is usually not what you want.
> +
>  config KERNEL_GZIP
>  	bool "Gzip"
>  	depends on HAVE_KERNEL_GZIP

It's odd to create CONFIG_KERNEL_UNCOMPRESSED and not use it for
anything, but I guess Kconfig's `choice' forces this.