Problem in First-Patch-Tutorial

[SIMRAN SINGHAL]

On Sun, Mar 19, 2017 at 6:53 PM, Alexander Kapshuk
<alexander.kapshuk at gmail.com> wrote:
> On Sun, Mar 19, 2017 at 10:53 AM, SIMRAN SINGHAL
> <singhalsimran0 at gmail.com> wrote:
>> # modinfo iio_dummy_evgen.ko
>> filename:
>> /home/simran/git/kernels/staging/drivers/iio/dummy/iio_dummy_evgen.ko
>> license:        GPL v2
>> description:    IIO dummy driver
>> author:         Jonathan Cameron <jic23 at kernel.org>
>> srcversion:     A8AC238EC07833E018CAF7B
>> depends:        industrialio
>> intree:         Y
>> vermagic:       4.11.0-rc1+ SMP mod_unload modversions
>>
>>
>> $ uname -r
>> 4.10.0-rc3+
>>
>> So, this shows that I need to compile module iio_dummy_evgen.ko for
>> kernel version 4.11.0-rc1, so for this I need to build system and
>> source tree for this version.
>>
>> So, I am trying this:-
>>  make -C /lib/modules/4.11.0-rc1+/build M=drivers/iio/dummy/ iio_dummy_evgen.ko
>>
>> But I don't know why I am getting this error:-
>> make: Entering directory '/home/simran/git/kernels/staging'
>> make[1]: *** No rule to make target 'iio_dummy_evgen.o'.  Stop.
>> Makefile:1664: recipe for target 'iio_dummy_evgen.ko' failed
>> make: *** [iio_dummy_evgen.ko] Error 2
>> make: Leaving directory '/home/simran/git/kernels/staging'
>>
>>
>> On Tue, Mar 14, 2017 at 12:19 AM,  <valdis.kletnieks at vt.edu> wrote:
>>> On Mon, 13 Mar 2017 15:38:07 +0530, SIMRAN SINGHAL said:
>>>
>>>> >> # modinfo iio_dummy_evgen.ko
>>>> >> filename:
>>>
>>>> >> vermagic:       4.11.0-rc1+ SMP mod_unload modversions
>>>> >>
>>>> >>
>>>> >> $ uname -r
>>>> >> 4.10.0-rc3+
>>>
>>>> Greg, I got that I have to build the module against the kernel I am using.
>>>> But, How can I do this?
>>>
>>> You can do this in two different ways:
>>>
>>> 1) You're running a 4.10.0-rc3+ kernel.  Get the matching 4.10.0-rc3+ source
>>> tree and build the module against that.
>>>
>>> 2) You built the module from a 4.11.0-rc1+ tree.  Build a kernel from that tree,
>>> boot that, and then try to load the module.
>>>
>>>
>
> You're running 4.10.0-rc3+.
> Your module is 4.11.0-rc1+.
> The command line you supplied shows you attempting to recompile your
> module for 4.11.0-rc1+. Your module is already 4.11.0-rc1+.
> As has been pointed out before, you need to either:
> (a). recompile your module for 4.10.0-rc3+.
> (b). or, install and boot into kernel 4.11.0-rc1+, and then try
> loading your module.



>
> As a side note, what kernel tree are you developing your driver
> against?

staging-testing

>The location of your staging drivers directory seems
> different from Linus' tree:
> ls -ld torvalds/drivers/staging/iio/
> drwxr-xr-x 14 sasha sasha 4096 Feb 13 21:24 torvalds/drivers/staging/iio/
>
> Finally, please do not top-post.

Sorry for this.