[Suggestion] Latest randconfig build errors for Head.S

[Suggestion] Latest randconfig build errors for Head.S

[Chen Gang]

Hello Maintainers:

  are these warnings for head.S OK ?


make:
  make V=1 EXTRA_CFLAGS=-W ARCH=arm randconfig
    (this time, CONFIG_MMU=y)

warning information:
  arch/arm/boot/compressed/head.S: Assembler messages:
  arch/arm/boot/compressed/head.S:565: Warning: (null)
  arch/arm/boot/compressed/head.S:676: Warning: (null)
  arch/arm/boot/compressed/head.S:698: Warning: (null)
  arch/arm/boot/compressed/head.S:722: Warning: (null)
  arch/arm/boot/compressed/head.S:726: Warning: (null)
  arch/arm/boot/compressed/head.S:735: Warning: (null)
  arch/arm/boot/compressed/head.S:978: Warning: (null)
  arch/arm/boot/compressed/head.S:1017: Warning: (null)
  arch/arm/boot/compressed/head.S:1018: Warning: (null)
  arch/arm/boot/compressed/head.S:1048: Warning: (null)
  arch/arm/boot/compressed/head.S:1055: Warning: (null)
  arch/arm/boot/compressed/head.S:1063: Warning: (null)
  arch/arm/boot/compressed/head.S:1074: Warning: (null)
  arch/arm/boot/compressed/head.S:1088: Warning: (null)
  arch/arm/boot/compressed/head.S:1120: Warning: (null)
  arch/arm/boot/compressed/head.S:1122: Warning: (null)
  arch/arm/boot/compressed/head.S:1123: Warning: (null)
  arch/arm/boot/compressed/head.S:1130: Warning: (null)
  arch/arm/boot/compressed/head.S:1162: Warning: (null)



-- 
Chen Gang

Asianux Corporation

Re: [Suggestion] Latest randconfig build errors for Head.S

[Russell King - ARM Linux]

On Thu, Mar 14, 2013 at 12:38:00PM +0800, Chen Gang wrote:
> Hello Maintainers:
> 
>   are these warnings for head.S OK ?
> 
> 
> make:
>   make V=1 EXTRA_CFLAGS=-W ARCH=arm randconfig
>     (this time, CONFIG_MMU=y)
> 
> warning information:
>   arch/arm/boot/compressed/head.S: Assembler messages:
>   arch/arm/boot/compressed/head.S:565: Warning: (null)
>   arch/arm/boot/compressed/head.S:676: Warning: (null)
>   arch/arm/boot/compressed/head.S:698: Warning: (null)
>   arch/arm/boot/compressed/head.S:722: Warning: (null)
>   arch/arm/boot/compressed/head.S:726: Warning: (null)
>   arch/arm/boot/compressed/head.S:735: Warning: (null)
>   arch/arm/boot/compressed/head.S:978: Warning: (null)
>   arch/arm/boot/compressed/head.S:1017: Warning: (null)
>   arch/arm/boot/compressed/head.S:1018: Warning: (null)
>   arch/arm/boot/compressed/head.S:1048: Warning: (null)
>   arch/arm/boot/compressed/head.S:1055: Warning: (null)
>   arch/arm/boot/compressed/head.S:1063: Warning: (null)
>   arch/arm/boot/compressed/head.S:1074: Warning: (null)
>   arch/arm/boot/compressed/head.S:1088: Warning: (null)
>   arch/arm/boot/compressed/head.S:1120: Warning: (null)
>   arch/arm/boot/compressed/head.S:1122: Warning: (null)
>   arch/arm/boot/compressed/head.S:1123: Warning: (null)
>   arch/arm/boot/compressed/head.S:1130: Warning: (null)
>   arch/arm/boot/compressed/head.S:1162: Warning: (null)

*Sigh*

So our wonderful toolchain has decided to start producing NULL warnings
for every "mcr     p15, 0, rX, c7, c10, 4" instruction?  I'd just ignore
them and hope that the toolchain people fix it.

Re: [Suggestion] Latest randconfig build errors for Head.S

[Chen Gang]

于 2013年03月15日 07:43, Russell King - ARM Linux 写道:
> So our wonderful toolchain has decided to start producing NULL warnings
> for every "mcr     p15, 0, rX, c7, c10, 4" instruction?  I'd just ignore
> them and hope that the toolchain people fix it.

  ok, thanks.

  :-)

-- 
Chen Gang

Asianux Corporation

Re: [Suggestion] Latest randconfig build errors for Head.S

[Andrea Adami]

On Fri, Mar 15, 2013 at 1:52 AM, Chen Gang <gang.chen@asianux.com> wrote:
> 于 2013年03月15日 07:43, Russell King - ARM Linux 写道:
>> So our wonderful toolchain has decided to start producing NULL warnings
>> for every "mcr     p15, 0, rX, c7, c10, 4" instruction?  I'd just ignore
>> them and hope that the toolchain people fix it.

AFAIK Arnd is aware and waiting for feedback about his patch:

ARM: compressed/head.S: work around new binutils warning   Arnd Bergmann

http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/144846.html

Regards

Andrea
>
>   ok, thanks.
>
>   :-)
>
> --
> Chen Gang
>
> Asianux Corporation
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [Suggestion] Latest randconfig build errors for Head.S

[Chen Gang]

于 2013年03月15日 17:31, Andrea Adami 写道:
> AFAIK Arnd is aware and waiting for feedback about his patch:
> 
> ARM: compressed/head.S: work around new binutils warning   Arnd Bergmann
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/144846.html

  excuse me, I am not familiar with arm assemble code, so can not give more information

  but at least for me, it seems your patch is more precious, and also welcomed by compiler.
  and I don't think your patch make the code "a more complex":
    the reason is:
    "keeping code simple and clear" is for readers and debuggers, not for writers.
    I prefer to write more code to let readers and debuggers easy understand.
      (if it has minor negative effect with performance)

  thanks.

-- 
Chen Gang

Asianux Corporation

Re: [Suggestion] Latest randconfig build errors for Head.S

[Arnd Bergmann]

On Friday 15 March 2013, Andrea Adami wrote:
> On Fri, Mar 15, 2013 at 1:52 AM, Chen Gang <gang.chen@asianux.com> wrote:
> > 于 2013年03月15日 07:43, Russell King - ARM Linux 写道:
> >> So our wonderful toolchain has decided to start producing NULL warnings
> >> for every "mcr     p15, 0, rX, c7, c10, 4" instruction?  I'd just ignore
> >> them and hope that the toolchain people fix it.
> 
> AFAIK Arnd is aware and waiting for feedback about his patch:
> 
> ARM: compressed/head.S: work around new binutils warning   Arnd Bergmann
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/144846.html

Right. The fact that as prints a warning for those instructions makes sense
given that we are telling it we want to run on *all* ARM architectures,
and that ARMv8 has deprecated them officially.

Of course, what is bogus about this is the "NULL" part rather than printing
the text that was meant to come out to explain the situation.  I don't
know how to report that bug other than what I tried before, but if it gets
fixed by printing the right text, we will still want to build a kernel
without getting any warnings.

	Arnd

Re: [Suggestion] Latest randconfig build errors for Head.S

[Chen Gang F T]

于 2013年03月15日 18:56, Arnd Bergmann 写道:
> Right. The fact that as prints a warning for those instructions makes sense
> given that we are telling it we want to run on *all* ARM architectures,
> and that ARMv8 has deprecated them officially.
> 
> Of course, what is bogus about this is the "NULL" part rather than printing
> the text that was meant to come out to explain the situation.  I don't
> know how to report that bug other than what I tried before, but if it gets
> fixed by printing the right text, we will still want to build a kernel
> without getting any warnings.

  excuse me, my English is not quite well.

  I guess your meaning is:
    "that bug" means the toolchain's bug (need toolchain people fix it).
    prefer to apply your patch, before "that bug" is fixed (we don't know when)

  is it correct ?

  thanks.

-- 
Chen Gang

Flying Transformer

Re: [Suggestion] Latest randconfig build errors for Head.S

[Arnd Bergmann]

On Friday 15 March 2013, Chen Gang F T wrote:
>   excuse me, my English is not quite well.
> 
>   I guess your meaning is:
>     "that bug" means the toolchain's bug (need toolchain people fix it).
>     prefer to apply your patch, before "that bug" is fixed (we don't know when)
> 
>   is it correct ?

Yes, correct.

	Arnd

Re: [Suggestion] Latest randconfig build errors for Head.S

[Chen Gang F T]

On 2013年03月15日 19:29, Arnd Bergmann wrote:
> On Friday 15 March 2013, Chen Gang F T wrote:
>> >   excuse me, my English is not quite well.
>> > 
>> >   I guess your meaning is:
>> >     "that bug" means the toolchain's bug (need toolchain people fix it).
>> >     prefer to apply your patch, before "that bug" is fixed (we don't know when)
>> > 
>> >   is it correct ?
> Yes, correct.

  thanks, and I support you.

-- 
Chen Gang

Flying Transformer