[PATCH] Arm64: Fix build error while switching from LE to BE

[PATCH] Arm64: Fix build error while switching from LE to BE

[Arun Chandran]

Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects
from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an
if_changed rule in the VDSO Makefile, we attempt to link a stale LE
object into the new BE kernel. According to Documentation/kbuild/makefiles.txt
FORCE is required for if_changed rules, and forgetting it is a common mistake

So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:

arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
failed to merge target specific data of file arch/arm64/kernel/vdso/note.o

arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o

Signed-off-by: Arun Chandran <achandran@mvista.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
---
 arch/arm64/kernel/vdso/Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index 6d20b7d..a268a9a 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
 	$(call if_changed,vdsosym)
 
 # Assembly rules for the .S files
-$(obj-vdso): %.o: %.S
+$(obj-vdso): %.o: %.S FORCE
 	$(call if_changed_dep,vdsoas)
 
 # Actual build commands
-- 
1.7.9.5

[PATCH] Arm64: Fix build error while switching from LE to BE

[Arun Chandran]

On Thu, Jun 26, 2014 at 3:16 PM, Arun Chandran <achandran@mvista.com> wrote:
> Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects
> from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an
> if_changed rule in the VDSO Makefile, we attempt to link a stale LE
> object into the new BE kernel. According to Documentation/kbuild/makefiles.txt
> FORCE is required for if_changed rules, and forgetting it is a common mistake
>
> So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:
>
> arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
> failed to merge target specific data of file arch/arm64/kernel/vdso/note.o
>
> arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
> failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o
>
> Signed-off-by: Arun Chandran <achandran@mvista.com>
> Tested-by: Mark Rutland <mark.rutland@arm.com>
> ---
>  arch/arm64/kernel/vdso/Makefile |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> index 6d20b7d..a268a9a 100644
> --- a/arch/arm64/kernel/vdso/Makefile
> +++ b/arch/arm64/kernel/vdso/Makefile
> @@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
>         $(call if_changed,vdsosym)
>
>  # Assembly rules for the .S files
> -$(obj-vdso): %.o: %.S
> +$(obj-vdso): %.o: %.S FORCE
>         $(call if_changed_dep,vdsoas)
>
>  # Actual build commands
> --
> 1.7.9.5
>

Any update on this?

--Arun

[PATCH] Arm64: Fix build error while switching from LE to BE

[Will Deacon]

On Wed, Jul 30, 2014 at 03:01:35PM +0100, Arun Chandran wrote:
> On Thu, Jun 26, 2014 at 3:16 PM, Arun Chandran <achandran@mvista.com> wrote:
> > Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects
> > from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an
> > if_changed rule in the VDSO Makefile, we attempt to link a stale LE
> > object into the new BE kernel. According to Documentation/kbuild/makefiles.txt
> > FORCE is required for if_changed rules, and forgetting it is a common mistake
> >
> > So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:
> >
> > arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
> > failed to merge target specific data of file arch/arm64/kernel/vdso/note.o
> >
> > arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
> > failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o
> >
> > Signed-off-by: Arun Chandran <achandran@mvista.com>
> > Tested-by: Mark Rutland <mark.rutland@arm.com>
> > ---
> >  arch/arm64/kernel/vdso/Makefile |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> > index 6d20b7d..a268a9a 100644
> > --- a/arch/arm64/kernel/vdso/Makefile
> > +++ b/arch/arm64/kernel/vdso/Makefile
> > @@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
> >         $(call if_changed,vdsosym)
> >
> >  # Assembly rules for the .S files
> > -$(obj-vdso): %.o: %.S
> > +$(obj-vdso): %.o: %.S FORCE
> >         $(call if_changed_dep,vdsoas)
> >
> >  # Actual build commands
> > --
> > 1.7.9.5
> >
> 
> Any update on this?

Sorry, this slipped through the cracks (neither myself or Catalin were on CC
and we didn't spot it on the list).

I've applied it to our for-next branch targetting 3.17 and will push out
after a bit of testing.

Will

[PATCH] Arm64: Fix build error while switching from LE to BE

[Arun Chandran]

Selecting CPU_BIG_ENDIAN and building the kernel fails just after
building it for little endian. According to Documentation/kbuild/makefiles.txt,
it is a common mistake to forget 'FORCE' while using 'if_changed'

So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:

arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
failed to merge target specific data of file arch/arm64/kernel/vdso/note.o

arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o

Signed-off-by: Arun Chandran <achandran@mvista.com>
---
 arch/arm64/kernel/vdso/Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index 6d20b7d..a268a9a 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
 	$(call if_changed,vdsosym)
 
 # Assembly rules for the .S files
-$(obj-vdso): %.o: %.S
+$(obj-vdso): %.o: %.S FORCE
 	$(call if_changed_dep,vdsoas)
 
 # Actual build commands
-- 
1.7.9.5

[PATCH] Arm64: Fix build error while switching from LE to BE

[Mark Rutland]

On Thu, Jun 26, 2014 at 07:46:44AM +0100, Arun Chandran wrote:
> Selecting CPU_BIG_ENDIAN and building the kernel fails just after
> building it for little endian. According to Documentation/kbuild/makefiles.txt,
> it is a common mistake to forget 'FORCE' while using 'if_changed'

This is a little confusing, because we jump from the high level problem
to a very specific problem detail with nothing to link the two.

How about:

Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects
from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an
if_changed rule in the VDSO Makefile, we attempt to link a stale LE
object into the new BE kernel. According to
Documentation/kbuild/makefiles.txt FORCE is required for if_changed
rules, and forgetting it is a common mistake.

> So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:
> 
> arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
> failed to merge target specific data of file arch/arm64/kernel/vdso/note.o
> 
> arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
> failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o
> 
> Signed-off-by: Arun Chandran <achandran@mvista.com>

Any reason for bot picking up my Tested-by [1]? The patch seems to be
the same.

Mark.

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-June/266571.html

> ---
>  arch/arm64/kernel/vdso/Makefile |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> index 6d20b7d..a268a9a 100644
> --- a/arch/arm64/kernel/vdso/Makefile
> +++ b/arch/arm64/kernel/vdso/Makefile
> @@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
>  	$(call if_changed,vdsosym)
>  
>  # Assembly rules for the .S files
> -$(obj-vdso): %.o: %.S
> +$(obj-vdso): %.o: %.S FORCE
>  	$(call if_changed_dep,vdsoas)
>  
>  # Actual build commands
> -- 
> 1.7.9.5
> 
> 

[PATCH] Arm64: Fix build error while switching from LE to BE

[Arun Chandran]

Hi,

On Thu, Jun 26, 2014 at 2:59 PM, Mark Rutland <mark.rutland@arm.com> wrote:
> On Thu, Jun 26, 2014 at 07:46:44AM +0100, Arun Chandran wrote:
>> Selecting CPU_BIG_ENDIAN and building the kernel fails just after
>> building it for little endian. According to Documentation/kbuild/makefiles.txt,
>> it is a common mistake to forget 'FORCE' while using 'if_changed'
>
> This is a little confusing, because we jump from the high level problem
> to a very specific problem detail with nothing to link the two.
>
> How about:
>
> Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects
> from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an
> if_changed rule in the VDSO Makefile, we attempt to link a stale LE
> object into the new BE kernel. According to
> Documentation/kbuild/makefiles.txt FORCE is required for if_changed
> rules, and forgetting it is a common mistake.
>

Yes that is a better one. I will make the change.

>> So fix it by 'Forcing' the build of vdso.  Fixes build errors like these:
>>
>> arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
>> failed to merge target specific data of file arch/arm64/kernel/vdso/note.o
>>
>> arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian
>> failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o
>>
>> Signed-off-by: Arun Chandran <achandran@mvista.com>
>
> Any reason for bot picking up my Tested-by [1]? The patch seems to be
> the same.

Sorry I missed that. Will include in my next patch

--Arun

>
> Mark.
>
> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-June/266571.html
>
>> ---
>>  arch/arm64/kernel/vdso/Makefile |    2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
>> index 6d20b7d..a268a9a 100644
>> --- a/arch/arm64/kernel/vdso/Makefile
>> +++ b/arch/arm64/kernel/vdso/Makefile
>> @@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
>>       $(call if_changed,vdsosym)
>>
>>  # Assembly rules for the .S files
>> -$(obj-vdso): %.o: %.S
>> +$(obj-vdso): %.o: %.S FORCE
>>       $(call if_changed_dep,vdsoas)
>>
>>  # Actual build commands
>> --
>> 1.7.9.5
>>
>>

[PATCH] Arm64: Fix build error while switching from LE to BE

[arun chandran]

Selecting CPU_BIG_ENDIAN and building the kernel fails just after
building it for little endian with the message

   VDSOA arch/arm64/kernel/vdso/gettimeofday.o
   VDSOL arch/arm64/kernel/vdso/vdso.so.dbg
/gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
arch/arm64/kernel/vdso/note.o: compiled for a little endian system and
target is big endian
/gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
failed to merge target specific data of file
arch/arm64/kernel/vdso/note.o
/gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system
and target is big endian
/gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
failed to merge target specific data of file
arch/arm64/kernel/vdso/sigreturn.o
collect2: error: ld returned 1 exit status
make[2]: *** [arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
make[1]: *** [arch/arm64/kernel/vdso] Error 2
make: *** [arch/arm64/kernel] Error 2
make: *** Waiting for unfinished jobs....

Fix it by 'Forcing' the build in arch/arm64/kernel/vdso/Makefile

Signed-off-by: Arun Chandran <achandran@mvista.com>
---
  arch/arm64/kernel/vdso/Makefile |    2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/vdso/Makefile 
b/arch/arm64/kernel/vdso/Makefile
index 6d20b7d..a268a9a 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
      $(call if_changed,vdsosym)

  # Assembly rules for the .S files
-$(obj-vdso): %.o: %.S
+$(obj-vdso): %.o: %.S FORCE
      $(call if_changed_dep,vdsoas)

  # Actual build commands
-- 
1.7.9.5

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[PATCH] Arm64: Fix build error while switching from LE to BE

[Mark Rutland]

On Wed, Jun 25, 2014 at 04:09:38PM +0100, arun chandran wrote:
> From 85134076eb06b90e295e46b083dc180a91c61ea2 Mon Sep 17 00:00:00 2001
> From: Arun Chandran <achandran@mvista.com>
> Date: Wed, 25 Jun 2014 19:36:54 +0530
> Subject: [PATCH] Arm64: Fix build error while switching from LE to BE
> 
> Selecting CPU_BIG_ENDIAN and building the kernel fails just after
> building it for little endian with the message
> 
>   VDSOA arch/arm64/kernel/vdso/gettimeofday.o
>   VDSOL arch/arm64/kernel/vdso/vdso.so.dbg
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> arch/arm64/kernel/vdso/note.o: compiled for a little endian system and
> target is big endian
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> failed to merge target specific data of file
> arch/arm64/kernel/vdso/note.o
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system
> and target is big endian
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> failed to merge target specific data of file
> arch/arm64/kernel/vdso/sigreturn.o
> collect2: error: ld returned 1 exit status
> make[2]: *** [arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
> make[1]: *** [arch/arm64/kernel/vdso] Error 2
> make: *** [arch/arm64/kernel] Error 2
> make: *** Waiting for unfinished jobs....
>
> Fix it by 'Forcing' the build in arch/arm64/kernel/vdso/Makefile

I see that Documentation/kbuild/makefiles.txt describes that if_changed
requires FORCE, and forgetting FORCE is a common mistake. See "6.7
Commands useful for building a boot image".

It's probably worth mentioning that in the commit message.

I was able to build and boot LE, BE, and LE arm64 (defconfig) kernels in
turn with this patch applied, and I didn't receive any unexpected errors
from gcc or ld.

So FWIW:

Tested-by: Mark Rutland <mark.rutland@arm.com>

Thanks,
Mark.

> Signed-off-by: Arun Chandran <achandran@mvista.com>
> ---
>  arch/arm64/kernel/vdso/Makefile |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> index 6d20b7d..a268a9a 100644
> --- a/arch/arm64/kernel/vdso/Makefile
> +++ b/arch/arm64/kernel/vdso/Makefile
> @@ -43,7 +43,7 @@ $(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
>  	$(call if_changed,vdsosym)
>  
>  # Assembly rules for the .S files
> -$(obj-vdso): %.o: %.S
> +$(obj-vdso): %.o: %.S FORCE
>  	$(call if_changed_dep,vdsoas)
>  
>  # Actual build commands
> -- 
> 1.7.9.5

[PATCH] Arm64: Fix build error while switching from LE to BE

[Geoff Levand]

Hi Arun,

On Wed, 2014-06-25 at 20:39 +0530, arun chandran wrote:
> Selecting CPU_BIG_ENDIAN and building the kernel fails just after
> building it for little endian with the message
> 
>    VDSOA arch/arm64/kernel/vdso/gettimeofday.o
>    VDSOL arch/arm64/kernel/vdso/vdso.so.dbg
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> arch/arm64/kernel/vdso/note.o: compiled for a little endian system and
> target is big endian
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> failed to merge target specific data of file
> arch/arm64/kernel/vdso/note.o
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system
> and target is big endian
> /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> failed to merge target specific data of file
> arch/arm64/kernel/vdso/sigreturn.o
> collect2: error: ld returned 1 exit status
> make[2]: *** [arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
> make[1]: *** [arch/arm64/kernel/vdso] Error 2
> make: *** [arch/arm64/kernel] Error 2
> make: *** Waiting for unfinished jobs....
> 
> Fix it by 'Forcing' the build in arch/arm64/kernel/vdso/Makefile
> 
> Signed-off-by: Arun Chandran <achandran@mvista.com>

This seems like a bit too much to put into the commit log.  What about
something like:

  Selecting CPU_BIG_ENDIAN and building the kernel fails just after
  building it for little endian.  Fix it by 'Forcing' the build of
  vdso.  Fixes build errors like these:

    arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian

-Geoff

[PATCH] Arm64: Fix build error while switching from LE to BE

[Arun Chandran]

Hi Geoff,


>
> On Wed, 2014-06-25 at 20:39 +0530, arun chandran wrote:
> > Selecting CPU_BIG_ENDIAN and building the kernel fails just after
> > building it for little endian with the message
> >
> >    VDSOA arch/arm64/kernel/vdso/gettimeofday.o
> >    VDSOL arch/arm64/kernel/vdso/vdso.so.dbg
> > /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> > arch/arm64/kernel/vdso/note.o: compiled for a little endian system and
> > target is big endian
> > /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> > failed to merge target specific data of file
> > arch/arm64/kernel/vdso/note.o
> > /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> > arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system
> > and target is big endian
> > /gcc-linaro-aarch64_be-linux-gnu-4.9-2014.05_linux/bin/../lib/gcc/aarch64_be-linux-gnu/4.9.1/../../../../aarch64_be-linux-gnu/bin/ld:
> > failed to merge target specific data of file
> > arch/arm64/kernel/vdso/sigreturn.o
> > collect2: error: ld returned 1 exit status
> > make[2]: *** [arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
> > make[1]: *** [arch/arm64/kernel/vdso] Error 2
> > make: *** [arch/arm64/kernel] Error 2
> > make: *** Waiting for unfinished jobs....
> >
> > Fix it by 'Forcing' the build in arch/arm64/kernel/vdso/Makefile
> >
> > Signed-off-by: Arun Chandran <achandran@mvista.com>
>
> This seems like a bit too much to put into the commit log.  What about
> something like:
>
>   Selecting CPU_BIG_ENDIAN and building the kernel fails just after
>   building it for little endian.  Fix it by 'Forcing' the build of
>   vdso.  Fixes build errors like these:
>
>     arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian
>
Ok I will do that and resend it.

--Arun