How to retrieve version from kernel source (the right way)?

How to retrieve version from kernel source (the right way)?

[Michael Renzmann]

Hi all.

(Please CC: me, I'm not subscribed - although I'm following the list 
through gmane.org)

I'm working on Madwifi (a driver for wireless lan cards with Atheros 
chipset), which isn't part of the kernel (and probably won't ever be due 
to the binary-only HAL). As every third-party device driver madwifi 
needs to know which kernel version it is compiled for, at least for 
determining the proper location to install itself after compilation. 
But... what is the right way to do this?

We used to get the kernel version via "uname -r", but dropped that 
behaviour. Chances are good that one wants to build the driver for a 
kernel version other than the currently running kernel.

Then we started to grep VERSION, PATCHLEVEL, SUBLEVEL and EXTRAVERSION 
from the kernel's Makefile. This failed, since some distributors seem to 
use shell commands for at least one of those. Example from SuSE 9.1:
=== cut ===
VERSION = 2
PATCHLEVEL = 6
SUBLEVEL = 5
EXTRAVERSION = -$(shell echo $(CONFIG_RELEASE)-$(CONFIG_CFGNAME))
=== cut ===

Newer kernels also allow to set CONFIG_LOCALVERSION in .config.

It seems that include/linux/version.h holds the complete version 
information in UTS_RELEASE. Is it reliable to get the information from 
version.h? Or is there any other preferred method for this?

Bye, Mike

Re: How to retrieve version from kernel source (the right way)?

[Brice Goglin]

Michael Renzmann a écrit :
> Then we started to grep VERSION, PATCHLEVEL, SUBLEVEL and EXTRAVERSION 
> from the kernel's Makefile. This failed, since some distributors seem to 
> use shell commands for at least one of those. Example from SuSE 9.1:
> === cut ===
> VERSION = 2
> PATCHLEVEL = 6
> SUBLEVEL = 5
> EXTRAVERSION = -$(shell echo $(CONFIG_RELEASE)-$(CONFIG_CFGNAME))
> === cut ===
> 
> Newer kernels also allow to set CONFIG_LOCALVERSION in .config.

And you may also set some "localversion*" files in the source directory.
Their contents will be added too.

Brice

Re: How to retrieve version from kernel source (the right way)?

[Christoph Hellwig]

On Wed, Feb 09, 2005 at 09:17:35AM +0100, Michael Renzmann wrote:
> Hi all.
> 
> (Please CC: me, I'm not subscribed - although I'm following the list 
> through gmane.org)
> 
> I'm working on Madwifi (a driver for wireless lan cards with Atheros 
> chipset), which isn't part of the kernel (and probably won't ever be due 
> to the binary-only HAL).

Why don't you use the reverse-engineered HAL from OpenBSD?

Re: How to retrieve version from kernel source (the right way)?

[Sam Ravnborg]

> But... what is the right way to do this?

I think you are looking for:
make kernelrelease

   Sam

Re: How to retrieve version from kernel source (the right way)?

[Michael Renzmann]

Hi.

Sam Ravnborg wrote:
>>But... what is the right way to do this?
> I think you are looking for:
> make kernelrelease

otaku@gimli linux-2.6.10 $ make kernelrelease
make: *** No rule to make target `kernelrelease'.  Stop.
otaku@gimli linux-2.6.10 $ cd ..
otaku@gimli src $ cd linux-2.4.28
otaku@gimli linux-2.4.28 $ make kernelrelease
make: *** No rule to make target `kernelrelease'.  Stop.
otaku@gimli linux-2.4.28 $

I don't think this will help.

Including the kernel's Makefile also is no option, I think ("rulespace 
pollution").

Bye, Mike

Re: How to retrieve version from kernel source (the right way)?

[Michael Renzmann]

Hi.

Andreas Gruenbacher wrote:
> A backward-compatible replacement for the new kernelrelease (which was added 
> only 8 weeks ago) rule is:
> 
> echo -e 'foo:\n\t@echo $(KERNELRELEASE)\ninclude Makefile' \
>     | make -f-

Thanks a lot, that works great!

Bye, Mike

Re: How to retrieve version from kernel source (the right way)?

[Sam Ravnborg]

On Thu, Feb 10, 2005 at 08:06:34AM +0100, Michael Renzmann wrote:
> Hi.
> 
> Sam Ravnborg wrote:
> >>But... what is the right way to do this?
> >I think you are looking for:
> >make kernelrelease
> 
> otaku@gimli linux-2.6.10 $ make kernelrelease
> make: *** No rule to make target `kernelrelease'.  Stop.
> otaku@gimli linux-2.6.10 $ cd ..
> otaku@gimli src $ cd linux-2.4.28
> otaku@gimli linux-2.4.28 $ make kernelrelease
> make: *** No rule to make target `kernelrelease'.  Stop.
> otaku@gimli linux-2.4.28 $
> 
> I don't think this will help.
> 
> Including the kernel's Makefile also is no option, I think ("rulespace 
> pollution").

I works with the 2.6 kernel.

	Sam

Re: How to retrieve version from kernel source (the right way)?

[Michael Renzmann]

Hi.

Sam Ravnborg wrote:
>>otaku@gimli linux-2.6.10 $ make kernelrelease
>>make: *** No rule to make target `kernelrelease'.  Stop.
> I works with the 2.6 kernel.

As Andreas Gruenbacher pointed out, this feature has been implemented 
just about 8 weeks ago. He also gave the following snippet as a backward 
compatible solution:

=== cut ===
echo -e 'foo:\n\t@echo $(KERNELRELEASE)\ninclude Makefile' \
     | make -f-
=== cut ===

This works fine.

Thanks to everyone for your tips and answers.

Bye, Mike