[PATCH 01/12] ARM: assembler: introduce adr_l, ldr_l and str_l macros

[Nick Desaulniers]

On Tue, Sep 15, 2020 at 12:35 AM Ard Biesheuvel <ardb at kernel.org> wrote:
>
> On Mon, 14 Sep 2020 at 12:57, Ard Biesheuvel <ardb at kernel.org> wrote:
> >
> > diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
> > index feac2c8b86f2..39e972eaaa3f 100644
> > --- a/arch/arm/include/asm/assembler.h
> > +++ b/arch/arm/include/asm/assembler.h
> > @@ -494,4 +494,88 @@ THUMB(     orr     \reg , \reg , #PSR_T_BIT        )
> >  #define _ASM_NOKPROBE(entry)
> >  #endif
> >
> > +       .macro          __adldst_l, op, reg, sym, tmp, c
> > +       .if             __LINUX_ARM_ARCH__ < 7
> > +       ldr\c           \tmp, .La\@
> > +       .subsection     1
> > +       .align          2
> > +.La\@: .long           \sym - .Lpc\@
> > +       .previous
> > +       .else
> > +       .ifnb           \c
> > + THUMB(        ittt            \c                      )
> > +       .endif
> > +       movw\c          \tmp, #:lower16:\sym - .Lpc\@
> > +       movt\c          \tmp, #:upper16:\sym - .Lpc\@
> > +       .endif
> > +
> > +#ifndef CONFIG_THUMB2_KERNEL
> > +       .set            .Lpc\@, . + 8                   // PC bias
> > +       .ifc            \op, add
> > +       add\c           \reg, \tmp, pc
> > +       .else
> > +       \op\c           \reg, [\tmp, pc]
>
> This should be
>
>        \op\c           \reg, [pc, \tmp]

That looks better.  I had tested this series yesterday and wasn't able
to build with either toolchains.  Was going to ask if I was using the
wrong base or if there was an issue with my version binutils.  All
good now, I'll try to hammer on this a bit.
-- 
Thanks,
~Nick Desaulniers