diff mbox

[v3,-next,5/5] Kconfig: Make x86 and arm kernels default to the LZ4-compressed

Message ID 1362484056-9778-6-git-send-email-kyungsik.lee@lge.com (mailing list archive)
State New, archived
Headers show

Commit Message

Kyungsik Lee March 5, 2013, 11:47 a.m. UTC
This patch makes x86 and arm kernels default to the LZ4-compressed
to test new LZ4 code in the linux-next. This is requested by
Andrew Morton.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
---
 init/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Borislav Petkov March 5, 2013, 11:58 a.m. UTC | #1
On Tue, Mar 05, 2013 at 08:47:36PM +0900, Kyungsik Lee wrote:
> This patch makes x86 and arm kernels default to the LZ4-compressed
> to test new LZ4 code in the linux-next. This is requested by
> Andrew Morton.
> 
> Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
> ---
>  init/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/init/Kconfig b/init/Kconfig
> index fc8eb1f..de3cb00 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -138,7 +138,7 @@ config HAVE_KERNEL_LZ4
>  
>  choice
>  	prompt "Kernel compression mode"
> -	default KERNEL_GZIP
> +	default KERNEL_LZ4

Do I understand it correctly that when this thing gets committed, kernel
builds on all systems missing the lz4 tool will fail and everybody
should go running to get it so that everybody can build kernels again?

WTF?
Florian Fainelli March 5, 2013, 12:04 p.m. UTC | #2
Hello,

On 03/05/2013 12:47 PM, Kyungsik Lee wrote:
> This patch makes x86 and arm kernels default to the LZ4-compressed
> to test new LZ4 code in the linux-next. This is requested by
> Andrew Morton.

I do not think making this the default is good idea, because the lz4demo 
utility that you need to actually compress the kernel (used in patch 2) 
is not installed nor available by default on most systems, while gzip 
is. Considering that such a concern was already raised in your v2 
patchset, I am surprised to see this.
--
Florian
H. Peter Anvin March 5, 2013, 4:13 p.m. UTC | #3
I'm ok with this only if the patch is clearly marked LINUS DO NOT MERGE.

Kyungsik Lee <kyungsik.lee@lge.com> wrote:

>This patch makes x86 and arm kernels default to the LZ4-compressed
>to test new LZ4 code in the linux-next. This is requested by
>Andrew Morton.
>
>Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
>---
> init/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/init/Kconfig b/init/Kconfig
>index fc8eb1f..de3cb00 100644
>--- a/init/Kconfig
>+++ b/init/Kconfig
>@@ -138,7 +138,7 @@ config HAVE_KERNEL_LZ4
> 
> choice
> 	prompt "Kernel compression mode"
>-	default KERNEL_GZIP
>+	default KERNEL_LZ4
>	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.
Andrew Morton March 5, 2013, 11:08 p.m. UTC | #4
On Tue, 05 Mar 2013 13:04:20 +0100 Florian Fainelli <florian@openwrt.org> wrote:

> Hello,
> 
> On 03/05/2013 12:47 PM, Kyungsik Lee wrote:
> > This patch makes x86 and arm kernels default to the LZ4-compressed
> > to test new LZ4 code in the linux-next. This is requested by
> > Andrew Morton.
> 
> I do not think making this the default is good idea, because the lz4demo 
> utility that you need to actually compress the kernel (used in patch 2) 
> is not installed nor available by default on most systems, while gzip 
> is.

Yes, that's a showstopper even for linux-next.  What a shame.

It means this code will walk into mainline with practically zero
third-party testing.  Oh well, the risk is minor.  If it breaks, people
can switch back to gzip easily enough.
Florian Fainelli March 6, 2013, 9:57 a.m. UTC | #5
On 03/06/2013 12:08 AM, Andrew Morton wrote:
> On Tue, 05 Mar 2013 13:04:20 +0100 Florian Fainelli <florian@openwrt.org> wrote:
>
>> Hello,
>>
>> On 03/05/2013 12:47 PM, Kyungsik Lee wrote:
>>> This patch makes x86 and arm kernels default to the LZ4-compressed
>>> to test new LZ4 code in the linux-next. This is requested by
>>> Andrew Morton.
>>
>> I do not think making this the default is good idea, because the lz4demo
>> utility that you need to actually compress the kernel (used in patch 2)
>> is not installed nor available by default on most systems, while gzip
>> is.
>
> Yes, that's a showstopper even for linux-next.  What a shame.
>
> It means this code will walk into mainline with practically zero
> third-party testing.  Oh well, the risk is minor.  If it breaks, people
> can switch back to gzip easily enough.

If we want to have more coverage, how about importing the lz4demo 
utility source code to tools/lz4/, and change scripts/Makefile.lib to 
point at it? Once the lz4 utilities have reached a broader audience and 
are available with most distributions, we could revert back to assuming 
this utility can be found in PATH.
--
Florian
Borislav Petkov March 6, 2013, 11:16 a.m. UTC | #6
On Wed, Mar 06, 2013 at 10:57:52AM +0100, Florian Fainelli wrote:
> If we want to have more coverage, how about importing the lz4demo
> utility source code to tools/lz4/

That looks like on overkill to me, besides I don't think that's the
purpose of tools/. Maybe everyone who wants to test this, should install
the tool and go wild without disturbing the default.

Thanks.
diff mbox

Patch

diff --git a/init/Kconfig b/init/Kconfig
index fc8eb1f..de3cb00 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -138,7 +138,7 @@  config HAVE_KERNEL_LZ4
 
 choice
 	prompt "Kernel compression mode"
-	default KERNEL_GZIP
+	default KERNEL_LZ4
 	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.