Build and Source Tree Requirements for Out-of-tree Modules

Build and Source Tree Requirements for Out-of-tree Modules

[Shea Levy]

Hi all,

I am a package maintainer for the kernel for the NixOS distribution. We 
support users building out-of-tree modules and other packages that might 
depend on the kernel source or build trees, but make modules_install 
copies the entire source and build trees (we build with $(O) set) to 
$(INSTALL_PATH), and those are some big paths to keep around. Is there 
any documentation on which of those files should actually be needed by 
any out-of-tree tools? For example I'm guessing the intermediate object 
files in the build tree or the .c files in the source tree are not 
necessary, but it would be nice if there were a definitive list of what 
could be removed to save space.

Regards,
Shea Levy

P.S. I am not subscribed to the list, please CC me in responses.

Re: Build and Source Tree Requirements for Out-of-tree Modules

[Austin S Hemmelgarn]

On 01/01/2014 10:11 AM, Shea Levy wrote:
> Hi all,
> 
> I am a package maintainer for the kernel for the NixOS
> distribution. We support users building out-of-tree modules and
> other packages that might depend on the kernel source or build
> trees, but make modules_install copies the entire source and build
> trees (we build with $(O) set) to $(INSTALL_PATH), and those are
> some big paths to keep around. Is there any documentation on which
> of those files should actually be needed by any out-of-tree tools?
> For example I'm guessing the intermediate object files in the build
> tree or the .c files in the source tree are not necessary, but it
> would be nice if there were a definitive list of what could be
> removed to save space.
Running 'make modules_prepare' in a clean source tree should set up
the sources with everything needed for out of tree modules, it largely
amounts to the .config file, a few scripts, and a couple of specific
other files.

Re: Build and Source Tree Requirements for Out-of-tree Modules

[Shea Levy]

Hi,

On 01/01/2014 03:04 PM, Austin S Hemmelgarn wrote:
> On 01/01/2014 10:11 AM, Shea Levy wrote:
>> Hi all,
>>
>> I am a package maintainer for the kernel for the NixOS
>> distribution. We support users building out-of-tree modules and
>> other packages that might depend on the kernel source or build
>> trees, but make modules_install copies the entire source and build
>> trees (we build with $(O) set) to $(INSTALL_PATH), and those are
>> some big paths to keep around. Is there any documentation on which
>> of those files should actually be needed by any out-of-tree tools?
>> For example I'm guessing the intermediate object files in the build
>> tree or the .c files in the source tree are not necessary, but it
>> would be nice if there were a definitive list of what could be
>> removed to save space.
> Running 'make modules_prepare' in a clean source tree should set up
> the sources with everything needed for out of tree modules, it largely
> amounts to the .config file, a few scripts, and a couple of specific
> other files.
>
Thanks so much! It looks like this can replace the build tree, so now 
all I need to figure out is how much of the source tree I can get rid 
of. The Makefile in the modules_prepare directory just basically 
re-calls make with -C /path/to/source/tree, so I need at least the 
Makefile...

~Shea Levy