Re: [PATCH/RFC] Re: linux-next: build failure after merge of the luto-misc tree

[Andy Lutomirski]

On Fri, Jul 22, 2016 at 10:08 PM, Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
> Hi Arnaldo,
>
> On Fri, 22 Jul 2016 16:57:34 -0300 Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:
>>
>> Em Fri, Jul 22, 2016 at 02:44:17PM -0500, Josh Poimboeuf escreveu:
>> > On Fri, Jul 22, 2016 at 04:36:55PM -0300, Arnaldo Carvalho de Melo wrote:
>> > > Em Fri, Jul 22, 2016 at 02:19:20PM -0500, Josh Poimboeuf escreveu:
>> > > > On Fri, Jul 22, 2016 at 11:37:39AM -0300, Arnaldo Carvalho de Melo wrote:
>> > > > > I.e. with the two patches I mentioned, that are equivalent to the last patch I
>> > > > > sent to Stephen for testing, we would end up with HOSTARCH=powerpc and
>> > > > > ARCH=x86, no?
>>
>> > > > Thanks for spelling it out, that helped a lot.
>>
>> > > Glad you liked it, I had to do it for my own sanity :-)
>>
>> > > And something that gave me mixed feelings was an e-mail from the kbuild
>> > > test bot that noticed my perf/core changes and said that the build was
>> > > broken for "make ARCH=x86_64", so I had to reinstate this part:
>>
>> > > ifeq ($(ARCH),x86_64)
>> > > ARCH := x86
>> > > endif
>>
>> > > Because, as you say, 'make ARCH=x86' works :-\ I think it will not be
>> > > needed with your patch, right? I'm checking your patch below right now,
>>
>> > Yeah, that shouldn't be needed with my patch.  I think either would
>> > work, but my patch is more of a permanent solution.
>>
>> Sure, I left it there because then we don't have bisection broke at that
>> fix I made, i.e. 'make ARCH=x86_64' works at that point too.
>>
>> I applied your patch and will push it to Ingo, now we must cross our
>> fingers so that Stephen doesn't come back to us once more telling it is
>> still broken :o)
>
> Unfortunately, this is what I get when I just build perf/core:
>
>   DESCEND  objtool
>   CC       /home/sfr/next/x86_64_allmodconfig/tools/objtool/builtin-check.o
>   LD       /home/sfr/next/x86_64_allmodconfig/tools/objtool/objtool-in.o
> Warning: objtool: x86 instruction decoder differs from kernel
>   LINK     /home/sfr/next/x86_64_allmodconfig/tools/objtool/objtool
> In file included from /home/sfr/next/next/arch/x86/include/uapi/asm/bitsperlong.h:10:0,
>                  from /home/sfr/next/next/include/uapi/asm-generic/int-ll64.h:11,
>                  from /home/sfr/next/next/include/uapi/asm-generic/types.h:6,
>                  from /home/sfr/next/next/arch/x86/include/uapi/asm/types.h:4,
>                  from /home/sfr/next/next/tools/include/linux/types.h:9,
>                  from /home/sfr/next/next/include/uapi/linux/elf.h:4,
>                  from /home/sfr/next/next/arch/x86/entry/vdso/vdso2c.c:66:
> /home/sfr/next/next/tools/include/asm-generic/bitsperlong.h:13:2: error: #error Inconsistent word size. Check asm/bitsperlong.h
>  #error Inconsistent word size. Check asm/bitsperlong.h
>   ^
>
> The be clear: this is a ppc64le hosted, x86_64 target cross build.
>
> I than added the following patch, and the build finishes successfully.
>
> From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> Date: Sat, 23 Jul 2016 14:35:40 +1000
> Subject: [PATCH] x86: make the vdso2c compiler use the host architecture
>  headers

Aha, I missed that bit in the makefile.

Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>

>
> Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> ---
>  arch/x86/entry/vdso/Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
> index 253b72eaade6..25e88c030c47 100644
> --- a/arch/x86/entry/vdso/Makefile
> +++ b/arch/x86/entry/vdso/Makefile
> @@ -55,7 +55,7 @@ VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
>  $(obj)/vdso64.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
>         $(call if_changed,vdso)
>
> -HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/x86/include/uapi
> +HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/$(SUBARCH)/include/uapi
>  hostprogs-y                    += vdso2c
>
>  quiet_cmd_vdso2c = VDSO2C  $@
> --
> 2.8.1
>
> There may be a more correct way to do this ...
> --
>Can  Cheers,
> Stephen Rothwell



-- 
Andy Lutomirski
AMA Capital Management, LLC