Patchwork linux-next: build failure after merge of the origin tree

On Wed, 10 Oct 2012 10:21:50 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:

> Hi Linus,
> 
> In Linus' tree, today's linux-next build (powerpc ppc64_defconfig) failed
> like this:
> 
> arch/powerpc/platforms/pseries/hotplug-memory.c: In function 'pseries_remove_memblock':
> arch/powerpc/platforms/pseries/hotplug-memory.c:103:17: error: unused variable 'pfn' [-Werror=unused-variable]
> 
> Caused by commit d760afd4d257 ("memory-hotplug: suppress "Trying to free
> nonexistent resource <XXXXXXXXXXXXXXXX-YYYYYYYYYYYYYYYY>" warning").
> 
> I can't see what the point of the "pfn" variable is

This:


> and this patch never
> appeared in linux-next before being merged.  :-(

It was first sighted October 3.

> I have reverted that commit for today.
> 
> If this patch truly was authored yesterday (according the Author Date in
> git), why was it merged yesterday while still under discussion?  And the
> latest update to it still has this build problem ... did anyone even try
> to build this for powerpc (since that architecture was obviously
> affected)?

Apparently not - the ppc bit was a best-effort fixup for a patch which
addresses an x86 problem.

Hi Stephen,

2012/10/10 8:45, Andrew Morton wrote:
> On Wed, 10 Oct 2012 10:21:50 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
>> Hi Linus,
>>
>> In Linus' tree, today's linux-next build (powerpc ppc64_defconfig) failed
>> like this:
>>
>> arch/powerpc/platforms/pseries/hotplug-memory.c: In function 'pseries_remove_memblock':
>> arch/powerpc/platforms/pseries/hotplug-memory.c:103:17: error: unused variable 'pfn' [-Werror=unused-variable]
>>
>> Caused by commit d760afd4d257 ("memory-hotplug: suppress "Trying to free
>> nonexistent resource <XXXXXXXXXXXXXXXX-YYYYYYYYYYYYYYYY>" warning").
>>
>> I can't see what the point of the "pfn" variable is
>
> This:
>
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c~a
> +++ a/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -101,7 +101,7 @@ static int pseries_remove_memblock(unsig
>   	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
>   	for (i = 0; i < sections_to_remove; i++) {
>   		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
> -		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
> +		ret = __remove_pages(zone, pfn, PAGES_PER_SECTION);
>   		if (ret)
>   			return ret;
>   	}

I believe the error to be fixed with this patch.
Could you try it?

Thanks,
Yasuaki Ishimatsu

>
>> and this patch never
>> appeared in linux-next before being merged.  :-(
>
> It was first sighted October 3.
>
>> I have reverted that commit for today.
>>
>> If this patch truly was authored yesterday (according the Author Date in
>> git), why was it merged yesterday while still under discussion?  And the
>> latest update to it still has this build problem ... did anyone even try
>> to build this for powerpc (since that architecture was obviously
>> affected)?
>
> Apparently not - the ppc bit was a best-effort fixup for a patch which
> addresses an x86 problem.
>

Hi Andrew,

On Tue, 9 Oct 2012 16:45:14 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Wed, 10 Oct 2012 10:21:50 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> 
> > I can't see what the point of the "pfn" variable is
> 
> This:
> 
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c~a
> +++ a/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -101,7 +101,7 @@ static int pseries_remove_memblock(unsig
>  	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
>  	for (i = 0; i < sections_to_remove; i++) {
>  		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
> -		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
> +		ret = __remove_pages(zone, pfn, PAGES_PER_SECTION);
>  		if (ret)
>  			return ret;
>  	}

Can we get that fix to Linus ASAP, please?

> > and this patch never
> > appeared in linux-next before being merged.  :-(
> 
> It was first sighted October 3.

Yeah, my mistake. But it never made it to linux-next.

> > I have reverted that commit for today.
> > 
> > If this patch truly was authored yesterday (according the Author Date in
> > git), why was it merged yesterday while still under discussion?  And the
> > latest update to it still has this build problem ... did anyone even try
> > to build this for powerpc (since that architecture was obviously
> > affected)?
> 
> Apparently not - the ppc bit was a best-effort fixup for a patch which
> addresses an x86 problem.

Right, and that is one of the reasons we have linux-next - to test for
cross architecture problems.

Hi,

On Wed, 10 Oct 2012 08:52:21 +0900 Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> wrote:
>
> 2012/10/10 8:45, Andrew Morton wrote:
> > On Wed, 10 Oct 2012 10:21:50 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> >
> >> Hi Linus,
> >>
> >> In Linus' tree, today's linux-next build (powerpc ppc64_defconfig) failed
> >> like this:
> >>
> >> arch/powerpc/platforms/pseries/hotplug-memory.c: In function 'pseries_remove_memblock':
> >> arch/powerpc/platforms/pseries/hotplug-memory.c:103:17: error: unused variable 'pfn' [-Werror=unused-variable]
> >>
> >> Caused by commit d760afd4d257 ("memory-hotplug: suppress "Trying to free
> >> nonexistent resource <XXXXXXXXXXXXXXXX-YYYYYYYYYYYYYYYY>" warning").
> >>
> >> I can't see what the point of the "pfn" variable is
> >
> > This:
> >
> > --- a/arch/powerpc/platforms/pseries/hotplug-memory.c~a
> > +++ a/arch/powerpc/platforms/pseries/hotplug-memory.c
> > @@ -101,7 +101,7 @@ static int pseries_remove_memblock(unsig
> >   	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
> >   	for (i = 0; i < sections_to_remove; i++) {
> >   		unsigned long pfn = start_pfn + i * PAGES_PER_SECTION;
> > -		ret = __remove_pages(zone, start_pfn,  PAGES_PER_SECTION);
> > +		ret = __remove_pages(zone, pfn, PAGES_PER_SECTION);
> >   		if (ret)
> >   			return ret;
> >   	}
> 
> I believe the error to be fixed with this patch.
> Could you try it?

The certainly fixes the build problem.  I can't comment in the semantics
of the patch.

Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>  (Build only)