Re: [PATCH 2/2] LoongArch: Add support for relocating the kernel with RELR relocation

[Xi Ruoyao]

On Sat, 2024-07-06 at 21:49 +0800, Huacai Chen wrote:
> On Sat, Jul 6, 2024 at 6:34 PM Xi Ruoyao <xry111@xxxxxxxxxxx> wrote:
> > 
> > On Sat, 2024-07-06 at 18:29 +0800, Huacai Chen wrote:
> > 
> > /* snip */
> > 
> > > > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> > > > index ddc042895d01..03b3ef5edd24 100644
> > > > --- a/arch/loongarch/Kconfig
> > > > +++ b/arch/loongarch/Kconfig
> > > > @@ -607,6 +607,7 @@ config
> > > > ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
> > > > 
> > > >  config RELOCATABLE
> > > >         bool "Relocatable kernel"
> > > > +       select ARCH_HAS_RELR
> > > Why is this selection under RELOCATABLE? I know ARM64 is the same,
> > > but
> > > why?
> > 
> > Because if we just select it in CONFIG_LOONGARCH instead of
> > CONFIG_RELOCATABLE, the users who have disabled CONFIG_RELOCATABLE
> > will
> > still see the entry for RELR in their configuration interface.  And
> > they'll ask "hey what's this for?  Why my kernel needs relocation?"
> RELR is not a similar conception to RELA, it is only used for
> relocatable kernel?

It replaces R_LARCH_RELATIVE relocs in RELA (basically represent the
same info in a much more compact form).  For non-relocatable kernel both
RELR and RELA shouldn't exist.

-- 
Xi Ruoyao <xry111@xxxxxxxxxxx>
School of Aerospace Science and Technology, Xidian University