Re: [PATCH 2/5] readelf: Adapt src/readelf -h/-S/-r/-w/-l/-d/-a on mips

[Mark Wielaard <mark@klomp.org>]

Hi Ying,

On Mon, 2023-07-24 at 16:35 +0800, Ying Huang wrote:
> Hi Mark,
> 
> > > diff --git a/libebl/eblreloctypecheck.c b/libebl/eblreloctypecheck.c
> > > index 80e67ef7..e3c43944 100644
> > > --- a/libebl/eblreloctypecheck.c
> > > +++ b/libebl/eblreloctypecheck.c
> > > @@ -32,10 +32,14 @@
> > > #endif
> > > 
> > >  #include 
> 
> > > -
> > > +#include 
> 
> > > 
> > > bool
> > > ebl_reloc_type_check (Ebl *ebl, int reloc)
> > > {
> > > - return ebl != NULL ? ebl->reloc_type_check (reloc) : false;
> > > + int relocNew = reloc;
> > > + GElf_Ehdr ehdr;
> > > + if(ebl->elf->class == ELFCLASS64 && gelf_getehdr(ebl->elf, &ehdr) != NULL && ehdr.e_machine == EM_MIPS)
> > > + relocNew = ELF64_MIPS_R_TYPE(reloc);
> > > + return ebl != NULL ? ebl->reloc_type_check (relocNew) : false;
> > > }
> > This should not go into the generic ebl_reloc_type_check but has to be
> > hooked so it uses a mips_reloc_type_check.
> > 
> > > diff --git a/libebl/eblreloctypename.c b/libebl/eblreloctypename.c
> > > index e53ec0c0..4276d8e3 100644
> > > --- a/libebl/eblreloctypename.c
> > > +++ b/libebl/eblreloctypename.c
> > > @@ -33,14 +33,18 @@
> > > 
> > >  #include 
> 
> > >  #include 
> 
> > > -
> > > +#include 
> 
> > > 
> > > const char *
> > > ebl_reloc_type_name (Ebl *ebl, int reloc, char *buf, size_t len)
> > > {
> > > const char *res;
> > > + int relocNew = reloc;
> > > + GElf_Ehdr ehdr;
> > > + if(ebl->elf->class == ELFCLASS64 && gelf_getehdr(ebl->elf, &ehdr) != NULL && ehdr.e_machine == EM_MIPS)
> > > + relocNew = ELF64_MIPS_R_TYPE(reloc);
> > > 
> > > - res = ebl != NULL ? ebl->reloc_type_name (reloc, buf, len) : NULL;
> > > + res = ebl != NULL ? ebl->reloc_type_name (relocNew, buf, len) : NULL;
> > > if (res == NULL)
> > > /* There are no generic relocation type names. */
> > >      res = "";
> > Likewise for hooking reloc_type_name.
> > 
> The function reloc_type_check and reloc_type_name were common hooks in file backends/common-reloc.c, so if we also need a new hook for mips and copy the check codes from common-reloc.c?

There are no other arches which use those hooks at the moment. But you
should be able to simply define them as mips_reloc_type_xxx and then
HOOK them in your mips.c init function.

Cheers,

Mark