proper way to create an out-of-tree kernel modules

proper way to create an out-of-tree kernel modules

[Kent Dorfman]

What is the proper way to create a recipe to build a kernel module
outside of the normal kernel tree?

The kernel sources need to be expanded and configured for the typical
kernel makefile line

make -C $(KERNEL_SRC) M=$(PWD) V=1 ARCH=$(ARCH) \
CROSS_COMPILE=$(CROSS_COMPILE) modules

to work.

Are there any sample/stubs available that demonstrate building and
deploying a simple kernel module?

TIA

Re: [yocto] proper way to create an out-of-tree kernel modules

[Quentin Schulz]

Hi Kent,

On Tue, Mar 03, 2020 at 09:32:55AM -0500, Kent Dorfman wrote:
> What is the proper way to create a recipe to build a kernel module
> outside of the normal kernel tree?
> 
> The kernel sources need to be expanded and configured for the typical
> kernel makefile line
> 
> make -C $(KERNEL_SRC) M=$(PWD) V=1 ARCH=$(ARCH) \
> CROSS_COMPILE=$(CROSS_COMPILE) modules
> 
> to work.
> 
> Are there any sample/stubs available that demonstrate building and
> deploying a simple kernel module?
> 

inherit module should usually be enough in the recipe AFAICT.

There might be some fixes to do in Makefiles but nothing crazy.

c.f. https://www.yoctoproject.org/docs/current/mega-manual/mega-manual.html#incorporating-out-of-tree-modules
http://git.yoctoproject.org/cgit.cgi/poky/tree/meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb

Quentin

Re: [yocto] proper way to create an out-of-tree kernel modules

[Kent Dorfman]

On 3/3/20, Quentin Schulz <quentin.schulz@streamunlimited.com> wrote:
> Hi Kent,
>
> On Tue, Mar 03, 2020 at 09:32:55AM -0500, Kent Dorfman wrote:
>> What is the proper way to create a recipe to build a kernel module
>> outside of the normal kernel tree?
>>
>> The kernel sources need to be expanded and configured for the typical
>> kernel makefile line
>>
>> make -C $(KERNEL_SRC) M=$(PWD) V=1 ARCH=$(ARCH) \
>> CROSS_COMPILE=$(CROSS_COMPILE) modules
>>
>> to work.
>>
>> Are there any sample/stubs available that demonstrate building and
>> deploying a simple kernel module?
>>
>
> inherit module should usually be enough in the recipe AFAICT.
>
> There might be some fixes to do in Makefiles but nothing crazy.
>
> c.f.
> https://www.yoctoproject.org/docs/current/mega-manual/mega-manual.html#incorporating-out-of-tree-modules
> http://git.yoctoproject.org/cgit.cgi/poky/tree/meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb
>
> Quentin
>

THANKS!  Will give this a try once my software raid is done resyncing.

I'm replacing the mainline slip driver with a custom one that tightly
binds the sl link name to the owned tty so that we know which sl
device is assigned to each slip connection.  Slip interface name is
normally assigned dynamically, which poses a problem trying to
identify 16 static tty slip connections.

Re: [yocto] proper way to create an out-of-tree kernel modules

[Kent Dorfman]

On 3/3/20, Kent Dorfman via Lists.Yoctoproject.Org
<kent.dorfman766=gmail.com@lists.yoctoproject.org> wrote:
> On 3/3/20, Quentin Schulz <quentin.schulz@streamunlimited.com> wrote:
>> Hi Kent,
>>
>> On Tue, Mar 03, 2020 at 09:32:55AM -0500, Kent Dorfman wrote:
>>> What is the proper way to create a recipe to build a kernel module
>>> outside of the normal kernel tree?
>>>
>>> The kernel sources need to be expanded and configured for the typical
>>> kernel makefile line
>>>
>>> make -C $(KERNEL_SRC) M=$(PWD) V=1 ARCH=$(ARCH) \
>>> CROSS_COMPILE=$(CROSS_COMPILE) modules
>>>
>>> to work.
>>>
>>> Are there any sample/stubs available that demonstrate building and
>>> deploying a simple kernel module?
>>>
>>
>> inherit module should usually be enough in the recipe AFAICT.
>>
>> There might be some fixes to do in Makefiles but nothing crazy.
>>
>> c.f.
>> https://www.yoctoproject.org/docs/current/mega-manual/mega-manual.html#incorporating-out-of-tree-modules
>> http://git.yoctoproject.org/cgit.cgi/poky/tree/meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb


Worked flawlessly. Thanks!