lkml.org 
[lkml]   [2017]   [Sep]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Problems compiling with KCFLAGS="-frecord-gcc-switches"
On Fri, Sep 29, 2017 at 01:00:56PM -0700, Guenter Roeck wrote:
> Hi Josh,
>
> when trying to compile an image with KCFLAGS="-frecord-gcc-switches",
> I get the folllowing build warning/error.
>
> make allmodconfig
> KCFLAGS="-frecord-gcc-switches" make arch/x86/kvm/emulate.o
> ./tools/objtool/objtool check --no-unreachable "arch/x86/kvm/emulate.o"
>
> arch/x86/kvm/emulate.o: warning:
> objtool: .GCC.command.line+0x0: special: can't find new instruction
>
> Building a full image aborts with:
>
> WARNING: arch/x86/kvm/kvm.o(__ex_table+0x4c): Section mismatch in reference
> from the (unknown reference) (unknown)
> to the variable .GCC.command.line:kvm_fastop_exception
> FATAL: The relocation at __ex_table+0x4c references
> section ".GCC.command.line" which is not executable, IOW
> the kernel will fault if it ever tries to
> jump to it. Something is seriously wrong
> and should be fixed.
> make[2]: *** [arch/x86/kvm/kvm.o] Error 1
>
> Any idea what might cause this problem ?
>

Here is another interesting problem, seen when building arm64 allmodconfig
-CONFIG_CPU_BIG_ENDIAN +CONFIG_EFI.

kallsyms failure:
relative symbol value 0xffffff9008073000 out of range in relative mode

This is due to symbols such as

000000000000000e n __efistub_$d

in the symbol table. Those are not filtered out by kallsyms, resulting in a
relative "base" address of 0x0e, and all other symbols are out of range.
Those symbols are only generated in efi/libstubs.

Any idea what might be going on there, and how to fix it ?
An easy fix would be something like

- else if (stype == 'N')
+ else if (toupper(stype) == 'N')

in kallsyms, but that doesn't seem like a clean solution to me.

Thanks,
Guenter

\
 
 \ /
  Last update: 2017-09-29 22:39    [W:0.060 / U:0.084 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site