[yocto] How do I patch the kernel before it is built?

[Bruce Ashfield]

On 12-02-06 5:10 PM, autif khan wrote:
> \>>>>>>>>>  I could not find a way to patch the kernel source before its is
>>>>>>>>>> built.
>>>>>>>>>>
>>>>>>>>>> I promise to update the Yocto wiki's How do I section when I have a
>>>>>>>>>> working solution for the following :-)
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> This should be covered in the existing documentation and also the
>>>>>>>>> more general bitbake/oe-core docs.
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Here is what I am trying to do:
>>>>>>>>>>
>>>>>>>>>> 1) Patch the kernel (add VID/PID to hid_ignore_list in
>>>>>>>>>> drivers/hid/hid-core.c and also to add the VID/PID to .h file)
>>>>>>>>>> 2) Build the kernel - no change here - standard kernel build
>>>>>>>>>> 3) Build a kernel module
>>>>>>>>>>
>>>>>>>>>> I have a meta layer where I am keeping my changes. I am guessing
>>>>>>>>>> that
>>>>>>>>>> I need to:
>>>>>>>>>>
>>>>>>>>>> a) write a bbappend file to accomplish #1
>>>>>>>>>> b) write a recipe to accomplish #3
>>>>>>>>>>
>>>>>>>>>> I have written recipes before, but just for libraries and autotools
>>>>>>>>>> based applications. Not for a kernel module. If there is a recipe
>>>>>>>>>> out
>>>>>>>>>> there for some other module, I would be happy to steal from it.
>>>>>>>>>>
>>>>>>>>>> Please advise how I can go about patching the kernel and if there
>>>>>>>>>> is
>>>>>>>>>> a
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> It's just like any other package. If your changes are simple, then
>>>>>>>>> generating patches and putting them on the SRC_URI via a bbappend in
>>>>>>>>> your layer is all you need. If you have complex changes, there are
>>>>>>>>> options
>>>>>>>>> to manage them via git or via feature descriptions.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> I tried this - attached at the end of this email are my bbappend file
>>>>>>> and my patches, when the recipe is bitbaked, it does not actually
>>>>>>> apply the patch.
>>>>>>>
>>>>>>> On a similar note - there seems to be a file in
>>>>>>> meta/recipes-kernel/linux/linux-yocto called
>>>>>>> tools-perf-no-scripting.patch
>>>>>>>
>>>>>>> However, it does not seem to be used anywhere - is this just crud or I
>>>>>>> am missing something? I was hoping to cheat off of the recipe that
>>>>>>> uses it.
>>>>>>>
>>>>>>>>>> recipe for a kernel module - please point me to it.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Darren validated and updated the kernel module example, so he'd
>>>>>>>>> probably
>>>>>>>>> got this closer at hand than I do.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> See the hello-mod example under meta/recipes-kernel/hello-mod
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Thank you for this recipe - it seems like this is exactly what I was
>>>>>>> looking for. I will cheat off of this as soon as I can patch my
>>>>>>> kernel.
>>>>>>>
>>>>>>>
>>>>>>> R E C I P E
>>>>>>>
>>>>>>> autif at fpbm:~/data/yocto/poky-edison-6.0/meta-koko/recipes/linux$ cat
>>>>>>> linux-yocto_3.0.bbappend
>>>>>>> FILESEXTRAPATHS_prepend := "${THISDIR}:"
>>>>>>> SRC_URI += " file://linux/drivers/hid/hid-core.c.diff \
>>>>>>>              file://linux/drivers/hid/hid-ids.h.diff "
>>>>>>> PR = "r3"
>>>>>>> autif at fpbm:~/data/yocto/poky-edison-6.0/meta-koko/recipes/linux$
>>>>>>>
>>>>>>> P A T C H
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> autif at fpbm:~/data/yocto/poky-edison-6.0/meta-koko/recipes/linux/linux/drivers/hid$
>>>>>>
>>>>>>
>>>>>>
>>>>>> Taking a look at this (while I was cutting and pasting), this should
>>>>>> be in in the
>>>>>> a 'linux-yocto' subdirectory if you want bitbake to pickup the patch
>>>>>> and
>>>>>> make it
>>>>>> available to the linux-yocto recipe.
>>>>>>
>>>>>> i.e.
>>>>>>
>>>>>> ~/data/yocto/poky-edison-6.0/meta-koko/recipes/linux/linux-yocto/drivers/hid
>>>>>>
>>>>>> And don't use 'linux-yocto' in your file:// reference on the SRC_URI,
>>>>>> that part is
>>>>>> automatic.
>>>>>
>>>>>
>>>>>
>>>>> I tried this just now - here is what happens:
>>>>>
>>>>> Case - patch is in linux/linux-yocto/drivers/hid, SRC_URI ref is
>>>>> file://drivers/hid/file.diff
>>>>> Result: Fetcher failure for URL: 'file://drivers/hid/hid-core.c.diff
>>>>
>>>>
>>>>
>>>> If you get a fetcher failire, you have it in the wrong place.
>>>>
>>>> Note: this has nothing to do with the kernel and is a general
>>>> bitbake/oe-core question.
>>>>
>>>>
>>>>>
>>>>> Case - patch is in linux/linux-yocto/drivers/hid, SRC_URI ref is
>>>>> file://linux-yocto/drivers/hid/file.diff
>>>>
>>>>
>>>>
>>>> Interesting. I've never had to specify linux-yocto in my SRC_URIs,
>>>> so something strange it going on here.
>>>>
>>>> Does anyone else have ideas here ?
>>>>
>>>>
>>>>
>>>>> Result - my diff files are copied in a directory called linux-yocto in
>>>>>
>>>>>
>>>>> tmp/work/crownbay-poky-linux/linux-yocto-3.0.4+git1+d05450e4aef02c1b7137398ab3a9f8f96da74f52_1+2247da9131ea7e46ed4766a69bb1353dba22f873-r3
>>>>>
>>>>> These patches are not applied in
>>>>>
>>>>>
>>>>> tmp/work/crownbay-poky-linux/linux-yocto-3.0.4+git1+d05450e4aef02c1b7137398ab3a9f8f96da74f52_1+2247da9131ea7e46ed4766a69bb1353dba22f873-r3/linux
>>>>>
>>>>> Here is what the work directory looks like
>>>>>
>>>>>
>>>>>
>>>>> autif at fpbm:~/ssd/minimal/tmp/work/crownbay-poky-linux/linux-yocto-3.0.4+git1+d05450e4aef02c1b7137398ab3a9f8f96da74f52_1+2247da9131ea7e46ed4766a69bb1353dba22f873-r3$
>>>>> ls
>>>>> git  license-destdir  linux  linux-crownbay-standard-build  linux-yocto
>>>>>   temp
>>>>>
>>>>>
>>>>> autif at fpbm:~/ssd/minimal/tmp/work/crownbay-poky-linux/linux-yocto-3.0.4+git1+d05450e4aef02c1b7137398ab3a9f8f96da74f52_1+2247da9131ea7e46ed4766a69bb1353dba22f873-r3$
>>>>>
>>>>>
>>>>> I have attached the original set of files as a tar gzip.
>>>>
>>>>
>>>>
>>>> I'll take them for a spin.
>>>>
>>>>
>>>>>
>>>>>> (and yes, I see 'edison' was the branch now)
>>>>>
>>>>>
>>>>>
>>>>> Yes, I am using Yocto 1.0 - very soon I will migrate to M2 - pending
>>>>> tasks at hand :-)
>>>>
>>>>
>>>>
>>>> I'll have to dig up a 1.0 tree, since I don't have anything of that
>>>> vintage available to me.
>>>>
>>>> But I know that patched worked then, and am absolutely sure that it
>>>> works in 1.1 and master.
>>>
>>>
>>> OK, I switched to M2 release and now, I have a different error:
>>>
>>> Case - diff files are in recipes/linux/linux-yocto, SRC_URI is
>>> file://drivers/hid/hid-core.c.diff
>>> Result - ERROR: Function 'Fetcher failure for URL:
>>> 'file://drivers/hid/hid-core.c.diff'. Unable to fetch URL
>>> file://drivers/hid/hid-core.c.diff from any source.' failed
>>>
>>>
>>> Did, I misunderstood you when you said that I should rename the files
>>> dir to linux-yocto - the name of the recipe and remove it from the
>>> SRC_URI?
>>
>>
>> Every build that I do with my meta-kernel-dev has some out of tree
>> patches. It's a form of continual regression testing that I do out
>> of habit.
>>
>> My bbappend looks like this:
>>
>> SRC_URI =
>> "git://${KSRC_linux_yocto};protocol=file;nocheckout=1;branch=${KBRANCH},meta;name=machine,meta
>> \
>>            file://make.patch \
>>            file://subdir/make2.patch \
>>            file://subdir/make3.patch"
>>
>>
>>> pwd
>> /home/bruce/yocto/poky-extras/meta-kernel-dev/recipes-kernel/linux
>>> tree linux-yocto
>> linux-yocto
>> ├── make.patch
>> └── subdir
>>     ├── make2.patch
>>     └── make3.patch
>>
>> These are always applied to my build.
>>
>> Cheers,
>>
>> Bruce
>>
>
> I will try that next. However, it seems like something is wrong with
> my setup may be.
>
> I was reading the log.do_patch file and it seems like bitbake is
> mixing my build and recipes directory.

Thanks! I'll run some tests here and see what I can find.

Cheers,

Bruce

>
> The recipe and logs are attached in this email. Once again, I have
> switched to M2 now. This is no longer with Yocto 1.0.