build custom kernel under FreeBSD 12

[Norbert Koch]

I did some more testing.

When I copy the src tree and set $MAKEOBJDIRPREFIX accordingly, I can
run "make kernel-toolchain && make buildkernel" without problems.

The permission denied error comes only when I symlink /usr/src/* and only
copy sys/ to my local directory. So, my idea is that  FreeBSD12 differs
from 11 and 10 by using something like realpath in either some Makefile
or make itself.



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Am 2019-07-19 um 09:28 schrieb Gary Jennejohn:
> On Fri, 19 Jul 2019 08:40:05 +0200
> Norbert Koch <nkoch at demig.de> wrote:
>
>> Here is a typescript:
>>
>> 12.0-RELEASE-p7 (3) nk at entw-pr4 [~/src/kernel/src] $ export
>> MAKEOBJDIRPREFIX=`realpath tmp`
>> 12.0-RELEASE-p7 (3) nk at entw-pr4 [~/src/kernel/src] $ echo $MAKEOBJDIRPREFIX
>> /usr/home/nk/src/kernel/src/tmp
>>
>> 12.0-RELEASE-p7 (3) nk at entw-pr4 [~/src/kernel/src] $ make buildkernel
>> make[1]: "/usr/home/nk/src/kernel/src/Makefile.inc1" line 341:
>> SYSTEM_COMPILER: Determined that CC=cc matches the source tree. Not
>> bootstrapping a cross-compiler.
>> make[1]: "/usr/home/nk/src/kernel/src/Makefile.inc1" line 348:
>> SYSTEM_LINKER: libclang will be built for bootstrapping a cross-linker.
>>
>> --------------------------------------------------------------
>>   >>> Kernel build for GENERIC started on Fri Jul 19 08:34:27 CEST 2019
>> --------------------------------------------------------------
>> ===> GENERIC
>> mkdir -p /usr/src/sys
>>
>> --------------------------------------------------------------
>>   >>> stage 1: configuring the kernel
>> --------------------------------------------------------------
>> cd /usr/home/nk/src/kernel/src/sys/i386/conf;
>> PATH=/usr/src/tmp/legacy/usr/sbin:/usr/src/tmp/legacy/usr/bin:/usr/src/tmp/legacy/bin:/usr/src/tmp/usr/sbin:/usr/src/tmp/usr/bin:/sbin:/bin:/usr/sbin:/usr/bin
>> config__ -d /usr/src/sys/GENERIC__ -I
>> '/usr/home/nk/src/kernel/src/sys/i386/conf'
>> '/usr/home/nk/src/kernel/src/sys/i386/conf/GENERIC'
>> config: /usr/src/sys/GENERIC: Permission denied
>> *** Error code 2
>>
>> Stop.
>> make[1]: stopped in /usr/home/nk/src/kernel/src
>> *** Error code 1
>>
>> Stop.
>> make: stopped in /usr/home/nk/src/kernel/src
>>
> It's peculiar that you have a mix of /usr/src and /usr/home/nk/src.
> Looking at /usr/src/Makefile.inc1 it would appear that you may also
> have to set KRNLOBJDIR to /usr/home/nk/src/kernel/src.
>
> Does the tmp directory really exist?  Seems like a weird choice.
>
> I did what Ryan suggested and was able to make build{kernel,world}
> from /usr/src with no problem.  But I haven't modified the kernel
> sources.
>
>> Am 2019-07-18 um 19:22 schrieb Ryan Stone:
>>> How are you setting MAKEOBJDIRPREFIX?  It needs to be set in your
>>> environment, i.e.
>>>
>>> $ export MAKEOBJDIRPREFIX=$HOME/obj
>>> $ make buildkernel
>>>
>>> Trying 'make MAKEOBJDIRPREFIX=$HOME/obj buildkernel' will fail in
>>> strange ways due to how make passes arguments to sub-makes.
>>>
>>> On Thu, Jul 18, 2019 at 9:53 AM Norbert Koch <nkoch at demig.de> wrote:
>>>> Hello.
>>>>
>>>> I am obviously too stupid to figure out how to build a custom kernel
>>>> as non-root user in a non-standard directory.
>>>> Under FreeBSD9/10/11 I could put src/ under my own directory
>>>> and start a kernel-compilation by just setting $MAKEOBJDIRPREFIX
>>>> accordingly. Doing this under FreeBSD12 gives me 'permission denied'
>>>> with 'config -d /usr/src/sys/GENERIC ...'. Seems like ${KRNLOBJDIR} is
>>>> not set correctly while the other parameters to config are.
>>>> I see that Makefiles differ between 12 and older releases.
>>>> ${OBJTOP} vs. ${OBJTREE}?
>>>>
>>>> So, what am I doing wrong?
>>>>
>>>> Thank you for any help.

-- 
Dipl.-Ing. Norbert Koch
Entwicklung Prozessregler