arch/arm64/efi-stub.o rebuilding every time?

arch/arm64/efi-stub.o rebuilding every time?

[Will Deacon]

Hi guys,

If I build an arm64 kernel, then simply hit make again without changing
anything, I find that efi-stub.o is rebuilt every time (with an annoying
warning too, but I think you already know about that):


$ make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- -j8 Image
  CHK     include/config/kernel.release
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CALL    scripts/checksyscalls.sh
  CHK     include/generated/compile.h
  CC      arch/arm64/kernel/efi-stub.o
In file included from arch/arm64/kernel/efi-stub.c:44:0:
arch/arm64/kernel/../../../drivers/firmware/efi/fdt.c: In function ?update_fdt?:
arch/arm64/kernel/../../../drivers/firmware/efi/fdt.c:66:22: warning: unused variable ?name? [-Wunused-variable]
   const char *type, *name;
                      ^
  CHK     kernel/config_data.h
  LD      arch/arm64/kernel/built-in.o
  LINK    vmlinux
  LD      vmlinux.o
  MODPOST vmlinux.o
  GEN     .version
  CHK     include/generated/compile.h
  UPD     include/generated/compile.h
  CC      init/version.o
  LD      init/built-in.o
  KSYM    .tmp_kallsyms1.o
  KSYM    .tmp_kallsyms2.o
  LD      vmlinux
  SORTEX  vmlinux
  SYSMAP  System.map
  OBJCOPY arch/arm64/boot/Image


Does this actually need to be rebuilt, or is there a buggy Makefile
somewhere?

Will

arch/arm64/efi-stub.o rebuilding every time?

[Ard Biesheuvel]

On 3 July 2014 16:13, Will Deacon <will.deacon@arm.com> wrote:
> Hi guys,
>
> If I build an arm64 kernel, then simply hit make again without changing
> anything, I find that efi-stub.o is rebuilt every time (with an annoying
> warning too, but I think you already know about that):
>

Yep, I had noticed that as well. The reason is that it depends on
generated header files, which it shouldn't. There's already a patch
queued in Matt Fleming's tree for this:
https://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/commit/?h=next&id=86b2eb8cdffda7eef07b1d6e5464491df1e86ee9

-- 
Ard.

>
> $ make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- -j8 Image
>   CHK     include/config/kernel.release
>   CHK     include/generated/uapi/linux/version.h
>   CHK     include/generated/utsrelease.h
>   CALL    scripts/checksyscalls.sh
>   CHK     include/generated/compile.h
>   CC      arch/arm64/kernel/efi-stub.o
> In file included from arch/arm64/kernel/efi-stub.c:44:0:
> arch/arm64/kernel/../../../drivers/firmware/efi/fdt.c: In function ?update_fdt?:
> arch/arm64/kernel/../../../drivers/firmware/efi/fdt.c:66:22: warning: unused variable ?name? [-Wunused-variable]
>    const char *type, *name;
>                       ^
>   CHK     kernel/config_data.h
>   LD      arch/arm64/kernel/built-in.o
>   LINK    vmlinux
>   LD      vmlinux.o
>   MODPOST vmlinux.o
>   GEN     .version
>   CHK     include/generated/compile.h
>   UPD     include/generated/compile.h
>   CC      init/version.o
>   LD      init/built-in.o
>   KSYM    .tmp_kallsyms1.o
>   KSYM    .tmp_kallsyms2.o
>   LD      vmlinux
>   SORTEX  vmlinux
>   SYSMAP  System.map
>   OBJCOPY arch/arm64/boot/Image
>
>
> Does this actually need to be rebuilt, or is there a buggy Makefile
> somewhere?
>
> Will
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

arch/arm64/efi-stub.o rebuilding every time?

[Matt Fleming]

On Thu, 2014-07-03 at 16:16 +0200, Ard Biesheuvel wrote:
> On 3 July 2014 16:13, Will Deacon <will.deacon@arm.com> wrote:
> > Hi guys,
> >
> > If I build an arm64 kernel, then simply hit make again without changing
> > anything, I find that efi-stub.o is rebuilt every time (with an annoying
> > warning too, but I think you already know about that):
> >
> 
> Yep, I had noticed that as well. The reason is that it depends on
> generated header files, which it shouldn't. There's already a patch
> queued in Matt Fleming's tree for this:
> https://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/commit/?h=next&id=86b2eb8cdffda7eef07b1d6e5464491df1e86ee9

It sounds like that commit should actually be put into my 'urgent'
branch and sent to tip asap instead of being queued up for the next
merge window.

Objections?

arch/arm64/efi-stub.o rebuilding every time?

[Will Deacon]

On Fri, Jul 04, 2014 at 07:36:17AM +0100, Matt Fleming wrote:
> On Thu, 2014-07-03 at 16:16 +0200, Ard Biesheuvel wrote:
> > On 3 July 2014 16:13, Will Deacon <will.deacon@arm.com> wrote:
> > > Hi guys,
> > >
> > > If I build an arm64 kernel, then simply hit make again without changing
> > > anything, I find that efi-stub.o is rebuilt every time (with an annoying
> > > warning too, but I think you already know about that):
> > >
> > 
> > Yep, I had noticed that as well. The reason is that it depends on
> > generated header files, which it shouldn't. There's already a patch
> > queued in Matt Fleming's tree for this:
> > https://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/commit/?h=next&id=86b2eb8cdffda7eef07b1d6e5464491df1e86ee9
> 
> It sounds like that commit should actually be put into my 'urgent'
> branch and sent to tip asap instead of being queued up for the next
> merge window.
> 
> Objections?

Sounds good to me. You can also add my ack, if you like:

  Acked-by: Will Deacon <will.deacon@arm.com>

Will

arch/arm64/efi-stub.o rebuilding every time?

[Ard Biesheuvel]

On 4 July 2014 10:24, Will Deacon <will.deacon@arm.com> wrote:
> On Fri, Jul 04, 2014 at 07:36:17AM +0100, Matt Fleming wrote:
>> On Thu, 2014-07-03 at 16:16 +0200, Ard Biesheuvel wrote:
>> > On 3 July 2014 16:13, Will Deacon <will.deacon@arm.com> wrote:
>> > > Hi guys,
>> > >
>> > > If I build an arm64 kernel, then simply hit make again without changing
>> > > anything, I find that efi-stub.o is rebuilt every time (with an annoying
>> > > warning too, but I think you already know about that):
>> > >
>> >
>> > Yep, I had noticed that as well. The reason is that it depends on
>> > generated header files, which it shouldn't. There's already a patch
>> > queued in Matt Fleming's tree for this:
>> > https://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/commit/?h=next&id=86b2eb8cdffda7eef07b1d6e5464491df1e86ee9
>>
>> It sounds like that commit should actually be put into my 'urgent'
>> branch and sent to tip asap instead of being queued up for the next
>> merge window.
>>
>> Objections?
>
> Sounds good to me. You can also add my ack, if you like:
>
>   Acked-by: Will Deacon <will.deacon@arm.com>
>

+1