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ARM BPABI breakage
- From: Alan Modra <amodra at bigpond dot net dot au>
- To: binutils at sourceware dot org
- Date: Fri, 19 May 2006 10:20:10 +0930
- Subject: ARM BPABI breakage
The other day I noticed that my 2006-04-21 change to
assign_file_positions_except_relocs probably broke ARM BPABI PT_DYNAMIC
segment. The comment saying "If the section has not yet been assigned a
file position... so it will not be processed above" is no longer true,
because all sections have been processed by the time we hit that code.
This will result in p_filesz not being set. I also noticed the hack in
assign_file_positions_for_load_sections for PT_NOTE p_filesz, which of
course is working around exactly the same problem: Non-loaded segments
don't have p_filesz set. Fixed by setting p_filesz for all these
segments in assign_file_positions_for_non_load_sections.
Bugzilla 594 also mentioned that p_memsz was unexpectedly being set for
the PT_NOTE segment. That particular bug was likely introduced with
a 2004-09-22 change I made with changelog saying "Don't bother checking
SEC_ALLOC in PT_LOAD segments." Looks like I missed the fact that some
of the SEC_ALLOC checks I removed were for non-PT_LOAD segments.
Finally, I think we can safely increase p_align from maxpagesize in
demand-paged executables so long as p_vaddr and p_offset are congruent
modulo the alignment.
* elf.c (elf_fake_sections): Formatting.
(assign_file_positions_for_load_sections): Only add SEC_ALLOC
sections to p_memsz. Remove hack for PT_NOTE sections. Allow
section alignment to increase p_align for PT_LOAD.
(assign_file_positions_for_non_load_sections): Remove ARM BPABI
hack for PT_DYNAMIC. Instead, set p_filesz for all segments
other than PT_LOAD, and PT_NOTE in core.
Index: bfd/elf.c
===================================================================
RCS file: /cvs/src/src/bfd/elf.c,v
retrieving revision 1.337
diff -c -p -r1.337 elf.c
*** bfd/elf.c 17 May 2006 05:09:24 -0000 1.337
--- bfd/elf.c 18 May 2006 23:00:37 -0000
*************** elf_fake_sections (bfd *abfd, asection *
*** 2736,2743 ****
if ((asect->flags & SEC_GROUP) != 0)
this_hdr->sh_type = SHT_GROUP;
else if ((asect->flags & SEC_ALLOC) != 0
! && (((asect->flags & (SEC_LOAD | SEC_HAS_CONTENTS)) == 0)
! || (asect->flags & SEC_NEVER_LOAD) != 0))
this_hdr->sh_type = SHT_NOBITS;
else
this_hdr->sh_type = SHT_PROGBITS;
--- 2736,2743 ----
if ((asect->flags & SEC_GROUP) != 0)
this_hdr->sh_type = SHT_GROUP;
else if ((asect->flags & SEC_ALLOC) != 0
! && (((asect->flags & (SEC_LOAD | SEC_HAS_CONTENTS)) == 0)
! || (asect->flags & SEC_NEVER_LOAD) != 0))
this_hdr->sh_type = SHT_NOBITS;
else
this_hdr->sh_type = SHT_PROGBITS;
*************** assign_file_positions_for_load_sections
*** 4379,4384 ****
--- 4379,4389 ----
}
}
+ /* Set up p_filesz, p_memsz, p_align and p_flags from the section
+ maps. Set filepos for sections in PT_LOAD segments, and in
+ core files, for sections in PT_NOTE segments.
+ assign_file_positions_for_non_load_sections will set filepos
+ for other sections and update p_filesz for other segments. */
for (i = 0, secpp = m->sections; i < m->count; i++, secpp++)
{
asection *sec;
*************** assign_file_positions_for_load_sections
*** 4410,4417 ****
}
/* .tbss is special. It doesn't contribute to p_memsz of
normal segments. */
! else if ((flags & SEC_THREAD_LOCAL) == 0
! || p->p_type == PT_TLS)
{
/* The section VMA must equal the file position
modulo the page size. */
--- 4415,4423 ----
}
/* .tbss is special. It doesn't contribute to p_memsz of
normal segments. */
! else if ((flags & SEC_ALLOC) != 0
! && ((flags & SEC_THREAD_LOCAL) == 0
! || p->p_type == PT_TLS))
{
/* The section VMA must equal the file position
modulo the page size. */
*************** assign_file_positions_for_load_sections
*** 4475,4490 ****
p->p_filesz += sec->size;
p->p_memsz += sec->size;
}
- /* PR ld/594: Sections in note segments which are not loaded
- contribute to the file size but not the in-memory size. */
- else if (p->p_type == PT_NOTE
- && (flags & SEC_HAS_CONTENTS) != 0)
- p->p_filesz += sec->size;
/* .tbss is special. It doesn't contribute to p_memsz of
normal segments. */
! else if ((flags & SEC_THREAD_LOCAL) == 0
! || p->p_type == PT_TLS)
p->p_memsz += sec->size;
if (p->p_type == PT_TLS
--- 4481,4492 ----
p->p_filesz += sec->size;
p->p_memsz += sec->size;
}
/* .tbss is special. It doesn't contribute to p_memsz of
normal segments. */
! else if ((flags & SEC_ALLOC) != 0
! && ((flags & SEC_THREAD_LOCAL) == 0
! || p->p_type == PT_TLS))
p->p_memsz += sec->size;
if (p->p_type == PT_TLS
*************** assign_file_positions_for_load_sections
*** 4497,4503 ****
}
if (align > p->p_align
! && (p->p_type != PT_LOAD || (abfd->flags & D_PAGED) == 0))
p->p_align = align;
}
--- 4499,4507 ----
}
if (align > p->p_align
! && (p->p_type != PT_LOAD
! || (abfd->flags & D_PAGED) == 0
! || ((p->p_vaddr - p->p_offset) & (align - 1)) == 0))
p->p_align = align;
}
*************** assign_file_positions_for_non_load_secti
*** 4624,4650 ****
m != NULL;
m = m->next, p++)
{
! if (p->p_type != PT_LOAD && m->count > 0)
{
! BFD_ASSERT (! m->includes_filehdr && ! m->includes_phdrs);
! /* If the section has not yet been assigned a file position,
! do so now. The ARM BPABI requires that .dynamic section
! not be marked SEC_ALLOC because it is not part of any
! PT_LOAD segment, so it will not be processed above. */
! if (p->p_type == PT_DYNAMIC && m->sections[0]->filepos == 0)
! {
! Elf_Internal_Shdr ** const i_shdrpp = elf_elfsections (abfd);
!
! i = 1;
! while (i_shdrpp[i]->bfd_section != m->sections[0])
! ++i;
! off = (_bfd_elf_assign_file_position_for_section
! (i_shdrpp[i], off, TRUE));
! p->p_filesz = m->sections[0]->size;
}
- p->p_offset = m->sections[0]->filepos;
}
! if (m->count == 0)
{
if (m->includes_filehdr)
{
--- 4628,4651 ----
m != NULL;
m = m->next, p++)
{
! if (m->count != 0)
{
! if (p->p_type != PT_LOAD
! && (p->p_type != PT_NOTE || bfd_get_format (abfd) != bfd_core))
! {
! Elf_Internal_Shdr *hdr;
! BFD_ASSERT (!m->includes_filehdr && !m->includes_phdrs);
!
! hdr = &elf_section_data (m->sections[m->count - 1])->this_hdr;
! p->p_filesz = (m->sections[m->count - 1]->filepos
! - m->sections[0]->filepos);
! if (hdr->sh_type != SHT_NOBITS)
! p->p_filesz += hdr->sh_size;
!
! p->p_offset = m->sections[0]->filepos;
}
}
! else
{
if (m->includes_filehdr)
{
--
Alan Modra
IBM OzLabs - Linux Technology Centre