Re: Build failure on CONFIG_DEBUG_FORCE_WEAK_PER_CPU?

[Tejun Heo <tj@kernel.org>]

On 10/05/2010 09:23 AM, Namhyung Kim wrote:
> The following message is a courtesy copy of an article
> that has been posted to gmane.linux.kernel as well.
> 
> Hello,
> 
> When I tried to build 2.6.36-rc6 on x86_64 allyesconfig,
> I got following messages and the build was broken:
> 
>   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
>   LD      .tmp_vmlinux1
> ld: arch/x86/kernel/init_task.o:(.debug_info+0xeee): error: undefined reference to '__pcpu_scope_init_tss'
> ld: arch/x86/kernel/init_task.o:(.debug_info+0x1558): error: undefined reference to '__pcpu_unique_init_tss'
> ld: arch/x86/built-in.o:(.debug_info+0x2bed2): error: undefined reference to '__pcpu_unique_shared_msrs'
> ld: arch/x86/built-in.o:(.debug_info+0x2c037): error: undefined reference to '__pcpu_unique_cpu_tsc_khz'
> ld: arch/x86/built-in.o:(.debug_info+0x2c0ab): error: undefined reference to '__pcpu_unique_current_vcpu'
> ld: arch/x86/built-in.o:(.debug_info+0x5801a): error: undefined reference to '__pcpu_unique_vmxarea'
> ld: arch/x86/built-in.o:(.debug_info+0x58046): error: undefined reference to '__pcpu_unique_current_vmcs'
> ld: arch/x86/built-in.o:(.debug_info+0x58072): error: undefined reference to '__pcpu_unique_vcpus_on_cpu'
> ld: arch/x86/built-in.o:(.debug_info+0x5809e): error: undefined reference to '__pcpu_unique_host_gdt'
> ld: arch/x86/built-in.o:(.debug_info+0x6086f): error: undefined reference to '__pcpu_unique_svm_data'
> ld: arch/x86/built-in.o:(.debug_info+0x659ff): error: undefined reference to '__pcpu_scope_xen_vcpu'
> ld: arch/x86/built-in.o:(.debug_info+0x65a41): error: undefined reference to '__pcpu_scope_xen_vcpu_info'
> ld: arch/x86/built-in.o:(.debug_info+0x65b2c): error: undefined reference to '__pcpu_unique_xen_vcpu'
> ld: arch/x86/built-in.o:(.debug_info+0x65b42): error: undefined reference to '__pcpu_unique_xen_vcpu_info'
> ld: arch/x86/built-in.o:(.debug_info+0x65b96): error: undefined reference to '__pcpu_unique_idt_desc'
> ... (snipped)
> make[2]: *** [.tmp_vmlinux1] Error 1
> make[1]: *** [sub-make] Error 2
> make: *** [all] Error 2
> 
> After reading comments on CONFIG_DEBUG_FORCE_WEAK_PER_CPU, I am
> not sure whether it is intended or not. I think it's not, but
> I can't find any report about this though the change was made
> last year by 7c756e6e19e71f0327760d8955f7077118ebb2b1. Or Am I
> missing something?
> 
> Anyway, the breakage was due to conflict between
> CONFIG_DEBUG_FORCE_WEAK_PER_CPU and CONFIG_DEBUG_INFO. I think a
> kconfig dependency has to be set between them something like:

Weird, I just did an allyesconfig build (sans CONFIG_GCOV_KERNEL for
parallel build) and it worked just fine.  Which toolchain versions are
you using?  Can you create a minimal .config which reproduces the
build failure?

Thanks.

-- 
tejun