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In-Reply-To: <874kabp9fb.fsf@oldenburg.str.redhat.com>
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 23 Sep 2021 09:15:35 -0700
Message-ID: <CAMe9rOrSNcT_0iUqA9BHx9Z+oEqLjp+kJX8TCand3OkgvL69CA@mail.gmail.com>
Subject: Re: [PATCH v4] ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld
To: Florian Weimer <fweimer@redhat.com>
Cc: GNU C Library <libc-alpha@sourceware.org>,
 Siddhesh Poyarekar <siddhesh@sourceware.org>
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On Thu, Sep 23, 2021 at 9:02 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > We can define DL_RO_DYN_SECTION and do
> >
> > diff --git a/elf/rtld.c b/elf/rtld.c
> > index 8d2bba3d43..83adf1c5f5 100644
> > --- a/elf/rtld.c
> > +++ b/elf/rtld.c
> > @@ -547,6 +547,7 @@ _dl_start (void *arg)
> >
> >    /* Read our own dynamic section and fill in the info array.  */
> >    bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic ();
> > +  bootstrap_map.l_ld_readonly = DL_RO_DYN_SECTION;
> >    elf_get_dynamic_info (&bootstrap_map);
> >
> >  #if NO_TLS_OFFSET != 0
> >
> > Will this work?
>
> I think it should.  We can use DL_RO_DYN_SECTION to define a single,
> generic version of dl_relocate_ld, too.

Here is the patch:

https://sourceware.org/pipermail/libc-alpha/2021-September/131294.html

-- 
H.J.