Re: [gentoo-dev] Building against /usr/src/linux and linux-info.eclass

[Markos Chandras]

On 21 February 2013 18:49, Mike Gilbert <floppym@g.o> wrote:
> On Thu, Feb 21, 2013 at 1:42 PM, Anthony G. Basile
> <basile@××××××××××××××.edu> wrote:
>> Hi everyone,
>>
>> This issue has come up in a few bugs so I want to bounce it off the
>> community.  When building packages that need a configured kernel source
>> tree, many ebuilds inherit linux-info to find configuration info about the
>> kernel.  However, there is the running kernel with its configuration
>> (/proc/config.gz if it exists), there is the kernel source tree
>> (/usr/src/linux if it exists and is configured) and both of these can be of
>> a different version than linux-headers.  Since building modules consumes
>> headers from /usr/include/linux, but uses code from /usr/src/linux and then
>> these modules are expected to insmod against the running kernel, all of
>> which can be mismatched, we have a lot of room for breakage.  Eg. bug
>> #458014.
>>
>> Any ideas about how to deal cleanly with situations like that?
>>
>
> I'm no expert, but I always thought that modules are supposed to
> consume headers from the kernel source directory, not from
> /usr/include/linux.
>
> As well, the modules should be installed for whatever kernel version
> is present in /usr/src/linux (or KERNEL_DIR. This may be distinct from
> the currently running kernel.
>
> I think the headers in /usr/include/linux are there for building
> userspace programs, which would utilize the more stable userspace <->
> kernel API.
>

Yes, I think this is the case as well. I am not sure if modules use
the headers in /usr/include/linux. It feel wrong to me

-- 
Regards,
Markos Chandras - Gentoo Linux Developer
http://dev.gentoo.org/~hwoarang