Re: [PATCH] lkdtm: avoid link error on ARM

From: Greg Kroah-Hartman
Date: Fri Jun 17 2016 - 11:36:47 EST


On Fri, Jun 17, 2016 at 08:33:00AM -0700, Kees Cook wrote:
> On Fri, Jun 17, 2016 at 3:07 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> > The lkdtm_rodata file is built so that a function in it gets linked into
> > the .rodata ELF section. This works fine normally, but on 32-bit ARM
> > with really large kernels, it prevents the linker from inserting a
> > veneer for the call to __gnu_mcount_nc in case we are building with
> > "gcc -pg":
> >
> > drivers/misc/built-in.o: In function `lkdtm_rodata_do_nothing':
> > panel.c:(.rodata+0x1480): relocation truncated to fit: R_ARM_CALL against symbol `__gnu_mcount_nc' defined in .text section in arch/arm/kernel/built-in.o
> >
> > We probably never want the profiling code to be enabled for this file
> > anyway, so this just removes the option here, and for the sake of
> > consistency also in the lkdtm core module.
> >
> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> > Fixes: 9a49a528dcf3 ("lkdtm: add function for testing .rodata section")
>
> Looks fine to me, thanks!
>
> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
>
> Greg, can you take this into your tree for -next?

Yes,will do.