Question on building out-of-tree modules on the target

Question on building out-of-tree modules on the target

[Rifenbark, Scott M]

Hi, 

I have a section in the YP Linux Kernel Development Manual that talks about building out-of-tree-modules on the target - http://www.yoctoproject.org/docs/1.9/kernel-dev/kernel-dev.html#building-out-of-tree-modules-on-the-target.  In this this section is a simple statements saying "Briefly, the kernel-dev package is installed by default on all *.sdk images."  I talked to some people and they noted that this might be an oversimplification.  It was also noted that for lsb and rt sdk images the old kernel-dev is added but for sato-sdk the new kernel-devsrc is added.

The section I have does not even mention a kernel-devsrc.  I am wondering how accurate this section currently is.  I don't know much about this particular area and could use some help from anyone to make this section more technically accurate given the latest YP release.  

Thanks, 
Scott

Scott Rifenbark
Intel Corporation
Yocto Project Documentation
503.712.2702

Re: Question on building out-of-tree modules on the target

[Trevor Woerner]

Hi Scott,

On 05/18/15 10:42, Rifenbark, Scott M wrote:
> I have a section in the YP Linux Kernel Development Manual that talks about building out-of-tree-modules on the target - 

Interestingly enough, I was just reading through that document the other
day. As soon as I saw a section titled "Building Out-Of-Tree Modules _On
The Target_" I thought to myself "why would anyone be doing development
on the target and not the host?" and skipped to the next section.

If it were me, I'd just remove that section altogether. I'm of the
opinion that doing development work on the target is wrong (if for no
other reason than to prove your cross-development setup is working
correctly), but that's just me.

;-)

Re: Question on building out-of-tree modules on the target

[Nicholas Krause]

On May 29, 2015 3:21:04 PM EDT, Trevor Woerner <twoerner@gmail.com> wrote:
>Hi Scott,
>
>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>> I have a section in the YP Linux Kernel Development Manual that talks
>about building out-of-tree-modules on the target - 
>
>Interestingly enough, I was just reading through that document the
>other
>day. As soon as I saw a section titled "Building Out-Of-Tree Modules
>_On
>The Target_" I thought to myself "why would anyone be doing development
>on the target and not the host?" and skipped to the next section.
>
>If it were me, I'd just remove that section altogether. I'm of the
>opinion that doing development work on the target is wrong (if for no
>other reason than to prove your cross-development setup is working
>correctly), but that's just me.
>
>;-)
Your assuming the target isn't powerful enough for compiling. What if it is? Then this can make life easier if the target can do it and avoid cross compilers ,  however it's pretty rare. 
Nick
-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: Question on building out-of-tree modules on the target

[Trevor Woerner]

On 05/29/15 15:28, Nicholas Krause wrote:
> On May 29, 2015 3:21:04 PM EDT, Trevor Woerner <twoerner@gmail.com> wrote:
>> If it were me, I'd just remove that section altogether. I'm of the
>> opinion that doing development work on the target is wrong (if for no
>> other reason than to prove your cross-development setup is working
>> correctly), but that's just me.
>>
>> ;-)
> Your assuming the target isn't powerful enough for compiling. What if it is?

That's why I included that part in parenthesis :-) Many "embedded"
devices are well powerful enough for compiling, but doing all your
development on the host computer demonstrates your cross-development
environment is properly configured for all development tasks.

Re: Question on building out-of-tree modules on the target

[Nicholas Krause]

On May 29, 2015 3:37:34 PM EDT, Trevor Woerner <twoerner@gmail.com> wrote:
>On 05/29/15 15:28, Nicholas Krause wrote:
>> On May 29, 2015 3:21:04 PM EDT, Trevor Woerner <twoerner@gmail.com>
>wrote:
>>> If it were me, I'd just remove that section altogether. I'm of the
>>> opinion that doing development work on the target is wrong (if for
>no
>>> other reason than to prove your cross-development setup is working
>>> correctly), but that's just me.
>>>
>>> ;-)
>> Your assuming the target isn't powerful enough for compiling. What if
>it is?
>
>That's why I included that part in parenthesis :-) Many "embedded"
>devices are well powerful enough for compiling, but doing all your
>development on the host computer demonstrates your cross-development
>environment is properly configured for all development tasks.
This is exactly my thought too.  You many want to put in an explanation about this in the manual through. 
IMHO, 
Nick 

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: Question on building out-of-tree modules on the target

[Hart, Darren]

On 5/29/15, 12:21 PM, "Trevor Woerner" <twoerner@gmail.com> wrote:

>Hi Scott,
>
>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>> I have a section in the YP Linux Kernel Development Manual that talks
>>about building out-of-tree-modules on the target -
>
>Interestingly enough, I was just reading through that document the other
>day. As soon as I saw a section titled "Building Out-Of-Tree Modules _On
>The Target_" I thought to myself "why would anyone be doing development
>on the target and not the host?" and skipped to the next section.
>
>If it were me, I'd just remove that section altogether. I'm of the
>opinion that doing development work on the target is wrong (if for no
>other reason than to prove your cross-development setup is working
>correctly), but that's just me.
>
>;-)
>

I personally agree, but having it documented means I get to answer a lot
few emails about people insisting on doing this. The section stays.

-- 
Darren Hart
Intel Open Source Technology Center

Re: Question on building out-of-tree modules on the target

[Rifenbark, Scott M]

Ok - so we established that we want it... If I get some clarifications in there about the "rarity" of the situation that would allow someone to develop on the target and also the benefits of having a verified cross-development system if they were to develop on the host, does the rest of the section stand as is?  Are there any issues with it?

Thanks, 
Scott

>-----Original Message-----
>From: Hart, Darren
>Sent: Friday, May 29, 2015 12:40 PM
>To: Trevor Woerner; Rifenbark, Scott M; yocto@yoctoproject.org
>Cc: Wold, Saul
>Subject: Re: [yocto] Question on building out-of-tree modules on the target
>
>On 5/29/15, 12:21 PM, "Trevor Woerner" <twoerner@gmail.com> wrote:
>
>>Hi Scott,
>>
>>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>>> I have a section in the YP Linux Kernel Development Manual that talks
>>>about building out-of-tree-modules on the target -
>>
>>Interestingly enough, I was just reading through that document the
>>other day. As soon as I saw a section titled "Building Out-Of-Tree
>>Modules _On The Target_" I thought to myself "why would anyone be doing
>>development on the target and not the host?" and skipped to the next
>section.
>>
>>If it were me, I'd just remove that section altogether. I'm of the
>>opinion that doing development work on the target is wrong (if for no
>>other reason than to prove your cross-development setup is working
>>correctly), but that's just me.
>>
>>;-)
>>
>
>I personally agree, but having it documented means I get to answer a lot few
>emails about people insisting on doing this. The section stays.
>
>--
>Darren Hart
>Intel Open Source Technology Center
>

Re: Question on building out-of-tree modules on the target

[Hart, Darren]

On 5/29/15, 12:46 PM, "Rifenbark, Scott M" <scott.m.rifenbark@intel.com>
wrote:

>Ok - so we established that we want it... If I get some clarifications in
>there about the "rarity" of the situation that would allow someone to
>develop on the target and also the benefits of having a verified
>cross-development system if they were to develop on the host, does the
>rest of the section stand as is?  Are there any issues with it?


Adding something like:

"While the traditional Yocto Project development model would be to include
kernel modules as part of the normal build process, some developers find
it useful to build modules on the target."

This section is lagging the 1.8 addition of kernel-devsrc, which was not
applied uniformly across all included SDK images. There is probably a
patch necessary to do that for a 1.8 point release, and then this document
could be made to reflect that.

--
Darren

>
>Thanks, 
>Scott
>
>>-----Original Message-----
>>From: Hart, Darren
>>Sent: Friday, May 29, 2015 12:40 PM
>>To: Trevor Woerner; Rifenbark, Scott M; yocto@yoctoproject.org
>>Cc: Wold, Saul
>>Subject: Re: [yocto] Question on building out-of-tree modules on the
>>target
>>
>>On 5/29/15, 12:21 PM, "Trevor Woerner" <twoerner@gmail.com> wrote:
>>
>>>Hi Scott,
>>>
>>>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>>>> I have a section in the YP Linux Kernel Development Manual that talks
>>>>about building out-of-tree-modules on the target -
>>>
>>>Interestingly enough, I was just reading through that document the
>>>other day. As soon as I saw a section titled "Building Out-Of-Tree
>>>Modules _On The Target_" I thought to myself "why would anyone be doing
>>>development on the target and not the host?" and skipped to the next
>>section.
>>>
>>>If it were me, I'd just remove that section altogether. I'm of the
>>>opinion that doing development work on the target is wrong (if for no
>>>other reason than to prove your cross-development setup is working
>>>correctly), but that's just me.
>>>
>>>;-)
>>>
>>
>>I personally agree, but having it documented means I get to answer a lot
>>few
>>emails about people insisting on doing this. The section stays.
>>
>>--
>>Darren Hart
>>Intel Open Source Technology Center
>>
>
>


-- 
Darren Hart
Intel Open Source Technology Center

Re: Question on building out-of-tree modules on the target

[Rifenbark, Scott M]

Darren, 

Thanks for the extra information.  I will take action on it and then throw the URL to the section out here in the list for a look.

Scott

>-----Original Message-----
>From: Hart, Darren
>Sent: Friday, May 29, 2015 12:59 PM
>To: Rifenbark, Scott M; Trevor Woerner; yocto@yoctoproject.org
>Cc: Wold, Saul
>Subject: Re: [yocto] Question on building out-of-tree modules on the target
>
>On 5/29/15, 12:46 PM, "Rifenbark, Scott M" <scott.m.rifenbark@intel.com>
>wrote:
>
>>Ok - so we established that we want it... If I get some clarifications
>>in there about the "rarity" of the situation that would allow someone
>>to develop on the target and also the benefits of having a verified
>>cross-development system if they were to develop on the host, does the
>>rest of the section stand as is?  Are there any issues with it?
>
>
>Adding something like:
>
>"While the traditional Yocto Project development model would be to include
>kernel modules as part of the normal build process, some developers find it
>useful to build modules on the target."
>
>This section is lagging the 1.8 addition of kernel-devsrc, which was not applied
>uniformly across all included SDK images. There is probably a patch necessary
>to do that for a 1.8 point release, and then this document could be made to
>reflect that.
>
>--
>Darren
>
>>
>>Thanks,
>>Scott
>>
>>>-----Original Message-----
>>>From: Hart, Darren
>>>Sent: Friday, May 29, 2015 12:40 PM
>>>To: Trevor Woerner; Rifenbark, Scott M; yocto@yoctoproject.org
>>>Cc: Wold, Saul
>>>Subject: Re: [yocto] Question on building out-of-tree modules on the
>>>target
>>>
>>>On 5/29/15, 12:21 PM, "Trevor Woerner" <twoerner@gmail.com> wrote:
>>>
>>>>Hi Scott,
>>>>
>>>>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>>>>> I have a section in the YP Linux Kernel Development Manual that
>>>>>talks about building out-of-tree-modules on the target -
>>>>
>>>>Interestingly enough, I was just reading through that document the
>>>>other day. As soon as I saw a section titled "Building Out-Of-Tree
>>>>Modules _On The Target_" I thought to myself "why would anyone be
>>>>doing development on the target and not the host?" and skipped to the
>>>>next
>>>section.
>>>>
>>>>If it were me, I'd just remove that section altogether. I'm of the
>>>>opinion that doing development work on the target is wrong (if for no
>>>>other reason than to prove your cross-development setup is working
>>>>correctly), but that's just me.
>>>>
>>>>;-)
>>>>
>>>
>>>I personally agree, but having it documented means I get to answer a
>>>lot few emails about people insisting on doing this. The section
>>>stays.
>>>
>>>--
>>>Darren Hart
>>>Intel Open Source Technology Center
>>>
>>
>>
>
>
>--
>Darren Hart
>Intel Open Source Technology Center
>

Re: Question on building out-of-tree modules on the target

[Rifenbark, Scott M]

Hi,

I added a clarifying paragraph at the start of this section.  Also, for the last paragraph I mentioned kernel-devsrc.  I could not find any commits that I understood looking in poky for "kernel-devsrc" so from the comment you gave Darren about the package not being uniformly installed on all *.sdk images, I improvised.  Let me know of any corrections.

http://www.yoctoproject.org/docs/1.9/kernel-dev/kernel-dev.html#building-out-of-tree-modules-on-the-target

Thanks, 
Scott

>-----Original Message-----
>From: Hart, Darren
>Sent: Friday, May 29, 2015 12:59 PM
>To: Rifenbark, Scott M; Trevor Woerner; yocto@yoctoproject.org
>Cc: Wold, Saul
>Subject: Re: [yocto] Question on building out-of-tree modules on the target
>
>On 5/29/15, 12:46 PM, "Rifenbark, Scott M" <scott.m.rifenbark@intel.com>
>wrote:
>
>>Ok - so we established that we want it... If I get some clarifications
>>in there about the "rarity" of the situation that would allow someone
>>to develop on the target and also the benefits of having a verified
>>cross-development system if they were to develop on the host, does the
>>rest of the section stand as is?  Are there any issues with it?
>
>
>Adding something like:
>
>"While the traditional Yocto Project development model would be to include
>kernel modules as part of the normal build process, some developers find it
>useful to build modules on the target."
>
>This section is lagging the 1.8 addition of kernel-devsrc, which was not applied
>uniformly across all included SDK images. There is probably a patch necessary
>to do that for a 1.8 point release, and then this document could be made to
>reflect that.
>
>--
>Darren
>
>>
>>Thanks,
>>Scott
>>
>>>-----Original Message-----
>>>From: Hart, Darren
>>>Sent: Friday, May 29, 2015 12:40 PM
>>>To: Trevor Woerner; Rifenbark, Scott M; yocto@yoctoproject.org
>>>Cc: Wold, Saul
>>>Subject: Re: [yocto] Question on building out-of-tree modules on the
>>>target
>>>
>>>On 5/29/15, 12:21 PM, "Trevor Woerner" <twoerner@gmail.com> wrote:
>>>
>>>>Hi Scott,
>>>>
>>>>On 05/18/15 10:42, Rifenbark, Scott M wrote:
>>>>> I have a section in the YP Linux Kernel Development Manual that
>>>>>talks about building out-of-tree-modules on the target -
>>>>
>>>>Interestingly enough, I was just reading through that document the
>>>>other day. As soon as I saw a section titled "Building Out-Of-Tree
>>>>Modules _On The Target_" I thought to myself "why would anyone be
>>>>doing development on the target and not the host?" and skipped to the
>>>>next
>>>section.
>>>>
>>>>If it were me, I'd just remove that section altogether. I'm of the
>>>>opinion that doing development work on the target is wrong (if for no
>>>>other reason than to prove your cross-development setup is working
>>>>correctly), but that's just me.
>>>>
>>>>;-)
>>>>
>>>
>>>I personally agree, but having it documented means I get to answer a
>>>lot few emails about people insisting on doing this. The section
>>>stays.
>>>
>>>--
>>>Darren Hart
>>>Intel Open Source Technology Center
>>>
>>
>>
>
>
>--
>Darren Hart
>Intel Open Source Technology Center
>