[RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
defconfig that should be built by default.

However currently there is an assumption that KBUILD_DEFCONFIG points to
a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).

We would like to use a target, using merge_config, as our defconfig, so
adapt the logic in scripts/kconfig/Makefile to allow that.

To minimise the chance of breaking anything, we first check if
KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
target.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 scripts/kconfig/Makefile | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index aceaaed09811..b2b9c87cec50 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -96,9 +96,12 @@ savedefconfig: $(obj)/conf
 defconfig: $(obj)/conf
 ifeq ($(KBUILD_DEFCONFIG),)
 	$< $(silent) --defconfig $(Kconfig)
-else
+else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
 	@$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
 	$(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
+else
+	@$(kecho) "*** Default configuration is based on target '$(KBUILD_DEFCONFIG)'"
+	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG)
 endif
 
 %_defconfig: $(obj)/conf
-- 
2.1.4

[RFC PATCH 2/2] powerpc: Add ppc64le_defconfig

[Michael Ellerman]

Based directly on ppc64_defconfig using merge_config.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/Makefile | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index b9b4af2af9a5..3704db45a832 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -288,6 +288,10 @@ PHONY += pseries_le_defconfig
 pseries_le_defconfig:
 	$(call merge_into_defconfig,pseries_defconfig,le)
 
+PHONY += ppc64le_defconfig
+ppc64le_defconfig:
+	$(call merge_into_defconfig,ppc64_defconfig,le)
+
 PHONY += mpc85xx_defconfig
 mpc85xx_defconfig:
 	$(call merge_into_defconfig,mpc85xx_basic_defconfig,\
-- 
2.1.4

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michal Marek]

On 2015-09-23 07:40, Michael Ellerman wrote:
> +else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>  	@$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
>  	$(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
> +else
> +	@$(kecho) "*** Default configuration is based on target '$(KBUILD_DEFCONFIG)'"
> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG)
>  endif

What is the anticipated usage of this? The patch is not needed to make

  make ppc64le_defconfig

work with the second patch. If it was, this would create a loop anyway.

Michal

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On 23 September 2015 19:50:52 GMT+10:00, Michal Marek <mmarek@suse.com> wrote:
>On 2015-09-23 07:40, Michael Ellerman wrote:
>> +else ifneq ($(wildcard
>arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>>  	@$(kecho) "*** Default configuration is based on
>'$(KBUILD_DEFCONFIG)'"
>>  	$(Q)$< $(silent)
>--defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
>> +else
>> +	@$(kecho) "*** Default configuration is based on target
>'$(KBUILD_DEFCONFIG)'"
>> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG)
>>  endif
>
>What is the anticipated usage of this? The patch is not needed to make
>
>  make ppc64le_defconfig
>
>work with the second patch. If it was, this would create a loop anyway.

The idea is to make 'make defconfig' work when KBUILD_DEFCONFIG is ppc64le_defconfig (which happens for us when uname returns ppc64le) and additionally when ppc64le_defconfig is not a real file.

It doesn't work currently, but does with these two patches applied.

cheers

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

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michal Marek]

Dne 24.9.2015 v 00:16 Michael Ellerman napsal(a):
> 
> 
> On 23 September 2015 19:50:52 GMT+10:00, Michal Marek
> <mmarek@suse.com> wrote:
>> On 2015-09-23 07:40, Michael Ellerman wrote:
>>> +else ifneq ($(wildcard
>> arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>>> @$(kecho) "*** Default configuration is based on
>> '$(KBUILD_DEFCONFIG)'"
>>> $(Q)$< $(silent)
>> --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
>>> +else +	@$(kecho) "*** Default configuration is based on target
>> '$(KBUILD_DEFCONFIG)'"
>>> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG) endif
>> 
>> What is the anticipated usage of this? The patch is not needed to
>> make
>> 
>> make ppc64le_defconfig
>> 
>> work with the second patch. If it was, this would create a loop
>> anyway.
> 
> The idea is to make 'make defconfig' work when KBUILD_DEFCONFIG is
> ppc64le_defconfig (which happens for us when uname returns ppc64le)
> and additionally when ppc64le_defconfig is not a real file.

Ah, that makes sense. You can add

Acked-by: Michal Marek <mmarek@suse.com>

if you want.

Michal

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On Fri, 2015-09-25 at 22:46 +0200, Michal Marek wrote:
> Dne 24.9.2015 v 00:16 Michael Ellerman napsal(a):
> > 
> > 
> > On 23 September 2015 19:50:52 GMT+10:00, Michal Marek
> > <mmarek@suse.com> wrote:
> >> On 2015-09-23 07:40, Michael Ellerman wrote:
> >>> +else ifneq ($(wildcard
> >> arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
> >>> @$(kecho) "*** Default configuration is based on
> >> '$(KBUILD_DEFCONFIG)'"
> >>> $(Q)$< $(silent)
> >> --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
> >>> +else +	@$(kecho) "*** Default configuration is based on target
> >> '$(KBUILD_DEFCONFIG)'"
> >>> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG) endif
> >> 
> >> What is the anticipated usage of this? The patch is not needed to
> >> make
> >> 
> >> make ppc64le_defconfig
> >> 
> >> work with the second patch. If it was, this would create a loop
> >> anyway.
> > 
> > The idea is to make 'make defconfig' work when KBUILD_DEFCONFIG is
> > ppc64le_defconfig (which happens for us when uname returns ppc64le)
> > and additionally when ppc64le_defconfig is not a real file.
> 
> Ah, that makes sense. You can add
> 
> Acked-by: Michal Marek <mmarek@suse.com>
> 
> if you want.

Thanks. I'll assume by that you mean you're happy if I take both patches
through the powerpc tree.

cheers

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michal Marek]

On 2015-10-01 08:14, Michael Ellerman wrote:
> On Fri, 2015-09-25 at 22:46 +0200, Michal Marek wrote:
>> Dne 24.9.2015 v 00:16 Michael Ellerman napsal(a):
>>>
>>>
>>> On 23 September 2015 19:50:52 GMT+10:00, Michal Marek
>>> <mmarek@suse.com> wrote:
>>>> On 2015-09-23 07:40, Michael Ellerman wrote:
>>>>> +else ifneq ($(wildcard
>>>> arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>>>>> @$(kecho) "*** Default configuration is based on
>>>> '$(KBUILD_DEFCONFIG)'"
>>>>> $(Q)$< $(silent)
>>>> --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
>>>>> +else +	@$(kecho) "*** Default configuration is based on target
>>>> '$(KBUILD_DEFCONFIG)'"
>>>>> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG) endif
>>>>
>>>> What is the anticipated usage of this? The patch is not needed to
>>>> make
>>>>
>>>> make ppc64le_defconfig
>>>>
>>>> work with the second patch. If it was, this would create a loop
>>>> anyway.
>>>
>>> The idea is to make 'make defconfig' work when KBUILD_DEFCONFIG is
>>> ppc64le_defconfig (which happens for us when uname returns ppc64le)
>>> and additionally when ppc64le_defconfig is not a real file.
>>
>> Ah, that makes sense. You can add
>>
>> Acked-by: Michal Marek <mmarek@suse.com>
>>
>> if you want.
> 
> Thanks. I'll assume by that you mean you're happy if I take both patches
> through the powerpc tree.

Yes, I assumed that this was your plan.

Michal

Re: [RFC PATCH 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On Thu, 2015-10-01 at 08:50 +0200, Michal Marek wrote:
> On 2015-10-01 08:14, Michael Ellerman wrote:
> > On Fri, 2015-09-25 at 22:46 +0200, Michal Marek wrote:
> >> Dne 24.9.2015 v 00:16 Michael Ellerman napsal(a):
> >>> On 23 September 2015 19:50:52 GMT+10:00, Michal Marek
> >>> <mmarek@suse.com> wrote:
> >>>> On 2015-09-23 07:40, Michael Ellerman wrote:
> >>>>> +else ifneq ($(wildcard
> >>>> arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
> >>>>> @$(kecho) "*** Default configuration is based on
> >>>> '$(KBUILD_DEFCONFIG)'"
> >>>>> $(Q)$< $(silent)
> >>>> --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
> >>>>> +else +	@$(kecho) "*** Default configuration is based on target
> >>>> '$(KBUILD_DEFCONFIG)'"
> >>>>> +	$(Q)$(MAKE) -f $(srctree)/Makefile $(KBUILD_DEFCONFIG) endif
> >>>>
> >>>> What is the anticipated usage of this? The patch is not needed to
> >>>> make
> >>>>
> >>>> make ppc64le_defconfig
> >>>>
> >>>> work with the second patch. If it was, this would create a loop
> >>>> anyway.
> >>>
> >>> The idea is to make 'make defconfig' work when KBUILD_DEFCONFIG is
> >>> ppc64le_defconfig (which happens for us when uname returns ppc64le)
> >>> and additionally when ppc64le_defconfig is not a real file.
> >>
> >> Ah, that makes sense. You can add
> >>
> >> Acked-by: Michal Marek <mmarek@suse.com>
> >>
> >> if you want.
> > 
> > Thanks. I'll assume by that you mean you're happy if I take both patches
> > through the powerpc tree.
> 
> Yes, I assumed that this was your plan.

I didn't really have a plan :)

It's certainly easiest if I take it in my tree along with the new
ppc64le_defconfig, so I'll do that. Thanks.

cheers

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
> defconfig that should be built by default.
> 
> However currently there is an assumption that KBUILD_DEFCONFIG points to
> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
> 
> We would like to use a target, using merge_config, as our defconfig, so
> adapt the logic in scripts/kconfig/Makefile to allow that.
> 
> To minimise the chance of breaking anything, we first check if
> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
> target.
> 
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> Acked-by: Michal Marek <mmarek@suse.com>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75

cheers

Re: [RFC,2/2] powerpc: Add ppc64le_defconfig

[Michael Ellerman]

On Wed, 2015-23-09 at 05:40:35 UTC, Michael Ellerman wrote:
> Based directly on ppc64_defconfig using merge_config.
> 
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/2adc48a691866fbb3134dd3a

cheers

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Olof Johansson]

On Fri, Oct 2, 2015 at 12:47 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
>> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
>> defconfig that should be built by default.
>>
>> However currently there is an assumption that KBUILD_DEFCONFIG points to
>> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
>>
>> We would like to use a target, using merge_config, as our defconfig, so
>> adapt the logic in scripts/kconfig/Makefile to allow that.
>>
>> To minimise the chance of breaking anything, we first check if
>> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
>> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
>> target.
>>
>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>> Acked-by: Michal Marek <mmarek@suse.com>
>
> Applied to powerpc next.
>
> https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75

This breaks arm64 defconfig for me:

mkdir obj-tmp
make -f Makefile O=obj-tmp ARCH=arm64 defconfig
... watch loop of:
*** Default configuration is based on target 'defconfig'
  GEN     ./Makefile



-Olof

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On Tue, 2015-10-13 at 14:02 -0700, Olof Johansson wrote:
> On Fri, Oct 2, 2015 at 12:47 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> > On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
> >> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
> >> defconfig that should be built by default.
> >>
> >> However currently there is an assumption that KBUILD_DEFCONFIG points to
> >> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
> >>
> >> We would like to use a target, using merge_config, as our defconfig, so
> >> adapt the logic in scripts/kconfig/Makefile to allow that.
> >>
> >> To minimise the chance of breaking anything, we first check if
> >> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
> >> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
> >> target.
> >>
> >> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> >> Acked-by: Michal Marek <mmarek@suse.com>
> >
> > Applied to powerpc next.
> >
> > https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75
> 
> This breaks arm64 defconfig for me:
> 
> mkdir obj-tmp
> make -f Makefile O=obj-tmp ARCH=arm64 defconfig
> ... watch loop of:
> *** Default configuration is based on target 'defconfig'
>   GEN     ./Makefile

Crap, sorry. I knew I shouldn't have touched that code!

Does this fix it for you?

diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index b2b9c87..3043d6b 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -96,7 +96,7 @@ savedefconfig: $(obj)/conf
 defconfig: $(obj)/conf
 ifeq ($(KBUILD_DEFCONFIG),)
        $< $(silent) --defconfig $(Kconfig)
-else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
+else ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
        @$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
        $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
 else



$ make O=obj CROSS_COMPILE=/opt/cross/gcc-4.9.0-nolibc/aarch64-linux/bin/aarch64-linux- ARCH=arm64 defconfig
make[1]: Entering directory '/home/michael/kernels/linux-next/obj'
  HOSTCC  scripts/basic/fixdep
  GEN     ./Makefile
  HOSTCC  scripts/kconfig/conf.o
  SHIPPED scripts/kconfig/zconf.tab.c
  SHIPPED scripts/kconfig/zconf.lex.c
  SHIPPED scripts/kconfig/zconf.hash.c
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/conf
*** Default configuration is based on 'defconfig'
#
# configuration written to .config
#
make[1]: Leaving directory '/home/michael/kernels/linux-next/obj'
$ head obj/.config
#
# Automatically generated file; DO NOT EDIT.
# Linux/arm64 4.3.0-rc5 Kernel Configuration
#
CONFIG_ARM64=y
CONFIG_64BIT=y
CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
CONFIG_MMU=y
CONFIG_STACKTRACE_SUPPORT=y
CONFIG_ILLEGAL_POINTER_VALUE=0xdead000000000000


cheers

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Olof Johansson]

On Tue, Oct 13, 2015 at 4:43 PM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> On Tue, 2015-10-13 at 14:02 -0700, Olof Johansson wrote:
>> On Fri, Oct 2, 2015 at 12:47 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
>> > On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
>> >> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
>> >> defconfig that should be built by default.
>> >>
>> >> However currently there is an assumption that KBUILD_DEFCONFIG points to
>> >> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
>> >>
>> >> We would like to use a target, using merge_config, as our defconfig, so
>> >> adapt the logic in scripts/kconfig/Makefile to allow that.
>> >>
>> >> To minimise the chance of breaking anything, we first check if
>> >> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
>> >> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
>> >> target.
>> >>
>> >> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>> >> Acked-by: Michal Marek <mmarek@suse.com>
>> >
>> > Applied to powerpc next.
>> >
>> > https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75
>>
>> This breaks arm64 defconfig for me:
>>
>> mkdir obj-tmp
>> make -f Makefile O=obj-tmp ARCH=arm64 defconfig
>> ... watch loop of:
>> *** Default configuration is based on target 'defconfig'
>>   GEN     ./Makefile
>
> Crap, sorry. I knew I shouldn't have touched that code!
>
> Does this fix it for you?

Yes, it does, however:

>
> diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
> index b2b9c87..3043d6b 100644
> --- a/scripts/kconfig/Makefile
> +++ b/scripts/kconfig/Makefile
> @@ -96,7 +96,7 @@ savedefconfig: $(obj)/conf
>  defconfig: $(obj)/conf
>  ifeq ($(KBUILD_DEFCONFIG),)
>         $< $(silent) --defconfig $(Kconfig)
> -else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
> +else ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>         @$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
>         $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)

Do you need a $(srctree) prefix here too? I'm not entirely sure what I
would do to reproduce a run that goes down this path so I can't
confirm.


-Olof

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michael Ellerman]

On Wed, 2015-10-14 at 09:54 -0700, Olof Johansson wrote:
> On Tue, Oct 13, 2015 at 4:43 PM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> > On Tue, 2015-10-13 at 14:02 -0700, Olof Johansson wrote:
> >> On Fri, Oct 2, 2015 at 12:47 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> >> > On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
> >> >> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
> >> >> defconfig that should be built by default.
> >> >>
> >> >> However currently there is an assumption that KBUILD_DEFCONFIG points to
> >> >> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
> >> >>
> >> >> We would like to use a target, using merge_config, as our defconfig, so
> >> >> adapt the logic in scripts/kconfig/Makefile to allow that.
> >> >>
> >> >> To minimise the chance of breaking anything, we first check if
> >> >> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
> >> >> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
> >> >> target.
> >> >>
> >> >> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> >> >> Acked-by: Michal Marek <mmarek@suse.com>
> >> >
> >> > Applied to powerpc next.
> >> >
> >> > https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75
> >>
> >> This breaks arm64 defconfig for me:
> >>
> >> mkdir obj-tmp
> >> make -f Makefile O=obj-tmp ARCH=arm64 defconfig
> >> ... watch loop of:
> >> *** Default configuration is based on target 'defconfig'
> >>   GEN     ./Makefile
> >
> > Crap, sorry. I knew I shouldn't have touched that code!
> >
> > Does this fix it for you?
> 
> Yes, it does, however:
> 
> > diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
> > index b2b9c87..3043d6b 100644
> > --- a/scripts/kconfig/Makefile
> > +++ b/scripts/kconfig/Makefile
> > @@ -96,7 +96,7 @@ savedefconfig: $(obj)/conf
> >  defconfig: $(obj)/conf
> >  ifeq ($(KBUILD_DEFCONFIG),)
> >         $< $(silent) --defconfig $(Kconfig)
> > -else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
> > +else ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
> >         @$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
> >         $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
> 
> Do you need a $(srctree) prefix here too? I'm not entirely sure what I
> would do to reproduce a run that goes down this path so I can't
> confirm.

That is the path you're going down, now that it's fixed. That's the path where
KBUILD_DEFCONFIG is a real file, ie. the old behaviour.

I'm not sure why it doesn't have a $(srctree) there, but it's never had one.

It looks like it eventually boils down to zconf_fopen() which looks for the
file in both .  and $(srctree).

So I think we could add a $(srctree) there, it would be more obvious and not
rely on the zconf_fopen() behaviour, but I'd rather leave it as is and let
Michal do that as a cleanup later.

cheers

Re: [RFC, 1/2] scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target

[Michal Marek]

Dne 15.10.2015 v 05:27 Michael Ellerman napsal(a):
> On Wed, 2015-10-14 at 09:54 -0700, Olof Johansson wrote:
>> On Tue, Oct 13, 2015 at 4:43 PM, Michael Ellerman <mpe@ellerman.id.au> wrote:
>>> On Tue, 2015-10-13 at 14:02 -0700, Olof Johansson wrote:
>>>> On Fri, Oct 2, 2015 at 12:47 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
>>>>> On Wed, 2015-23-09 at 05:40:34 UTC, Michael Ellerman wrote:
>>>>>> Arch Makefiles can set KBUILD_DEFCONFIG to tell kbuild the name of the
>>>>>> defconfig that should be built by default.
>>>>>>
>>>>>> However currently there is an assumption that KBUILD_DEFCONFIG points to
>>>>>> a file at arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
>>>>>>
>>>>>> We would like to use a target, using merge_config, as our defconfig, so
>>>>>> adapt the logic in scripts/kconfig/Makefile to allow that.
>>>>>>
>>>>>> To minimise the chance of breaking anything, we first check if
>>>>>> KBUILD_DEFCONFIG is a file, and if so we do the old logic. If it's not a
>>>>>> file, then we call the top-level Makefile with KBUILD_DEFCONFIG as the
>>>>>> target.
>>>>>>
>>>>>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>>>>> Acked-by: Michal Marek <mmarek@suse.com>
>>>>>
>>>>> Applied to powerpc next.
>>>>>
>>>>> https://git.kernel.org/powerpc/c/d2036f30cfe1daa19e63ce75
>>>>
>>>> This breaks arm64 defconfig for me:
>>>>
>>>> mkdir obj-tmp
>>>> make -f Makefile O=obj-tmp ARCH=arm64 defconfig
>>>> ... watch loop of:
>>>> *** Default configuration is based on target 'defconfig'
>>>>   GEN     ./Makefile
>>>
>>> Crap, sorry. I knew I shouldn't have touched that code!
>>>
>>> Does this fix it for you?
>>
>> Yes, it does, however:
>>
>>> diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
>>> index b2b9c87..3043d6b 100644
>>> --- a/scripts/kconfig/Makefile
>>> +++ b/scripts/kconfig/Makefile
>>> @@ -96,7 +96,7 @@ savedefconfig: $(obj)/conf
>>>  defconfig: $(obj)/conf
>>>  ifeq ($(KBUILD_DEFCONFIG),)
>>>         $< $(silent) --defconfig $(Kconfig)
>>> -else ifneq ($(wildcard arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>>> +else ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)),)
>>>         @$(kecho) "*** Default configuration is based on '$(KBUILD_DEFCONFIG)'"
>>>         $(Q)$< $(silent) --defconfig=arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig)
>>
>> Do you need a $(srctree) prefix here too? I'm not entirely sure what I
>> would do to reproduce a run that goes down this path so I can't
>> confirm.
> 
> That is the path you're going down, now that it's fixed. That's the path where
> KBUILD_DEFCONFIG is a real file, ie. the old behaviour.
> 
> I'm not sure why it doesn't have a $(srctree) there, but it's never had one.
> 
> It looks like it eventually boils down to zconf_fopen() which looks for the
> file in both .  and $(srctree).

Yes, the kconfig frontends do part of what would ideally be the job of
make or the Makefile.

Michal