This change increases the default alignment for the .plt section
from 4 bytes to 8 bytes. When function descriptors are 8-byte
aligned, they can be updated atomically on 32-bit hppa. This
helps with ordering issues on SMP machines. It also ensures
that descriptors reside on the same cache line. This reduces
the probability of a double TLB miss in a call.
2019-10-20 John David Anglin <danglin@gcc.gnu.org>
* elf32-hppa.c (elf32_hppa_size_dynamic_sections): Provide 8-byte
minimum alignment for .plt section.
This commit updates the import stubs to leave the pointer to the
function descriptor in register %r22. This provides a backup
mechanism for _dl_runtime_resolve to fixup descriptors during
lazy binding.
bfd/ChangeLog
2019-10-19 John David Anglin <danglin@gcc.gnu.org>
* elf32-hppa.c: Revise import stub sequences.
(LONG_BRANCH_STUB_SIZE): Define.
(LONG_BRANCH_SHARED_STUB_SIZE): Define.
(IMPORT_STUB_SIZE): Define.
(IMPORT_SHARED_STUB_SIZE): Define.
(EXPORT_STUB_SIZE): Define.
(plt_stub): Revise to not use register %r22.
(LDO_R1_R22): Define.
(LDW_R22_R21): Define.
(LDW_R22_R19): Define.
(hppa_build_one_stub): Update stub generation and use new defines.
(hppa_size_one_stub): Likewise.
The last patch was enough to cure the testcase, but not the original
object file. This patch does the same for hppa as is done for ppc64,
simply test for the section belonging to a group. I've also
restricted stubs to load, alloc, code sections.
PR 23207
* elf32-hppa.c (hppa_get_stub_entry): Return NULL when link_sec
is NULL.
(elf32_hppa_size_stubs): Only create stubs for load, alloc, code
sections.
(final_link_relocate): Revert last change.
We don't create PLT call stubs for anything in non-alloc sections,
so it doesn't pay to go looking for them. The problem is that
non-alloc sections aren't processed by group_sections and thus don't
get a link_sec set up for them.
PR 23207
* elf32-hppa.c (final_link_relocate): Don't look for plt call
stubs in non-alloc sections.
We were emitting dynamic relocs on the second word of a TLS GD GOT
entry pair (the dtprel offset), without the addend necessary when no
symbol is present on the dynamic reloc. Unfortunately the simple
solution of providing the proper addend doesn't work due to an hppa
glibc ld.so bug that ignores such addends. So instead optimize the
relocs. The dtprel offset is known at link time for locally defined
symbols (the only case where we'll end up with no symbol on a dynamic
reloc) so we can omit the dynamic reloc in that case.
Furthermore, we can omit a dynamic reloc on the first word of a TLS GD
GOT entry pair (the module id) if the symbol is local and we are
producing an executable. Similarly, a tprel reloc on a TLS IE GOT
entry is not needed for local symbols in an executable. So the
condition for TLS GOT relocs can become bfd_link_dll(info) rather than
bfd_link_pic(info) as needed for normal GOT relocs.
This all presumes hppa ld.so doesn't need to differentiate TLS GD GOT
pairs from TLS LD GOT pairs, which is currently true.
PR 22978
* elf32-hppa.c (got_relocs_needed): Add extra param to special
case both dtprel and tprel relocs.
(allocate_dynrelocs): Adjust conditions for got relocs.
(elf32_hppa_relocate_section): Likewise for local sym got relocs.
Emit dynamic relocs on TLS GOT entries for shared libraries,
not when pic. Omit dynamic reloc on dtprel entry when local,
and on tprel entry when local and executable.
The only stub type that makes sense for undefined symbols, or those
defined in shared libraries, is a plt call stub. This patch arranges
to have "destination" set to -1 on such symbols, making for an easy
test in hppa_type_of_stub.
PR 22537
* elf32-hppa.c (elf32_hppa_size_stubs): Init "destination" to -1.
(hppa_type_of_stub): Don't return a long branch stub for
symbols other than those defined statically.
Many targets define their own dyn_relocs struct when they could use
struct elf_dyn_relocs. This patch tidies that, and uses
readonly_dynrelocs in a few more places.
The SH adjust_dynamic_symbol had some really weird code dating back to
2002 that looked over dynamic relocations for any in SEC_HAS_CONTENTS
or SEC_READONLY sections, rather than just the usual SEC_READONLY
sections. So basically any dynamic relocation. What's more, the SH
relocate_section has no support for emitting dynamic relocations in
non-PIC. In other words, SH has no support for avoiding copy relocs
in non-PIC. I've made that more obvious by using "if (0 && ..)" in
asjust_dynamic_symbol.
Unfortunately, LM32, M32R, NDS32, and OR1K copied the bogus SH
adjust_dynamic_symbol code. So none of those targets would have
avoided copy relocs. LM32, M32R, NDS32 get the "if (0)" treatment
too. (LM32 is even more broken in that non_got_ref is never set.)
OR1K relocate_section looks like it might support dynamic relocs in
non-PIC, so I've enabled the copy reloc avoidance code for that
target.
* elf32-hppa.c (struct elf32_hppa_dyn_reloc_entry): Delete. Use
struct elf_dyn_relocs throughout file instead.
(elf32_hppa_adjust_dynamic_symbol): Comment tidy.
* elf32-lm32.c (struct elf_lm32_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(lm32_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-m32r.c (struct elf_m32r_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(m32r_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-metag.c (struct elf_metag_dyn_reloc_entry): Delete. Use
struct elf_dyn_relocs throughout file instead.
(elf_metag_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-microblaze.c (struct elf32_mb_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(readonly_dynrelocs): New function.
(microblaze_elf_adjust_dynamic_symbol): Use it.
* elf32-nds32.c (struct elf_nds32_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(nds32_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-nios2.c (struct elf32_nios2_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
* elf32-or1k.c (struct elf_or1k_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(or1k_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-sh.c (struct elf_sh_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(sh_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-tilepro.c (struct tilepro_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(tilepro_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfnn-riscv.c (struct riscv_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(riscv_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfxx-sparc.c (struct _bfd_sparc_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(_bfd_sparc_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfxx-tilegx.c (struct tilegx_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(tilegx_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-s390.c (elf_s390_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf64-s390.c (elf_s390_adjust_dynamic_symbol): Use readonly_dynrelocs.
In early October, HJ Lu added support for a number of targets to "Dump
dynamic relocation in read-only section with minfo". This extends
that support to more targets, displays the symbol involved, and splits
the existing function that sets TEXTREL into a "readonly_dynrelocs"
and "maybe_set_textrel" function. I'll need "readonly_dynrelocs" if I
ever get around to fixing "pr22374 function pointer initialization"
fails.
am33_2.0, arc, bfin, hppa64, mn10300, and nios2 fail to mark a binary
needing text relocations with DT_TEXTREL. That's not good. xtensa also
fails to do so but complains about "dangerous relocation: dynamic
relocation in read-only section" so I reckon that is fine and have
marked the test as an xfail. The other targets need maintainer
attention.
Curiously, the map file dump wasn't added for x86, so the map test
currently fail on x86. It also fails on alpha, am33_2.0, arc, bfin,
hppa64, ia64, m68k, mips, mn10300, nios2, score and vax. cris
complains with "tmpdir/textrel.o, section .rodata: relocation
R_CRIS_32 should not be used in a shared object; recompile with -fPIC"
so I've marked it as an xfail.
bfd/
* elf32-hppa.c (maybe_set_textrel): Print symbol for map file output.
* elf32-ppc.c (maybe_set_textrel): Likewise.
* elf64-ppc.c (maybe_set_textrel): Likewise.
* elf32-arm.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(elf32_arm_readonly_dynrelocs): ..this.
* elf32-lm32.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-m32r.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-metag.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-nds32.c: Delete unnecessary forward declarations.
(readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-or1k.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-s390.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-sh.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-tic6x.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(elf32_tic6x_readonly_dynrelocs): ..this.
* elf32-tilepro.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf64-s390.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfnn-aarch64.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(aarch64_readonly_readonly_dynrelocs): ..this.
* elfnn-riscv.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfxx-sparc.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfxx-tilegx.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
ld/
* testsuite/ld-elf/shared.exp: Run new textrel tests.
* testsuite/ld-elf/textrel.map: New file.
* testsuite/ld-elf/textrel.rd: New file.
* testsuite/ld-elf/textrel.s: New file.
* testsuite/ld-elf/textrel.warn: New file.
This cleans up yet more craziness with non_got_ref.
PR 22533
* elf32-hppa.c (elf32_hppa_copy_indirect_symbol): Don't do anything
special with non_got_ref for weak aliases.
(elf32_hppa_check_relocs): Tweak setting of non_got_ref.
(elf32_hppa_adjust_dynamic_symbol): When initialising weak aliases,
don't uselessly copy non_got_ref. Clear dyn_relocs instead if
strong symbol is allocated in dynbss. Tidy comments.
(elf32_hppa_relocate_section): Comment fix.
* elf32-ppc.c (ppc_elf_copy_indirect_symbol): Don't do anything
special with non_got_ref for weak aliases.
(ppc_elf_adjust_dynamic_symbol): When initialising weak aliases,
don't uselessly copy non_got_ref. Clear dyn_relocs instead if
strong symbol is allocated in dynbss. Tidy comments.
* elf64-ppc.c (ppc64_elf_copy_indirect_symbol): Don't do anything
special with non_got_ref for weak aliases.
(ppc64_elf_adjust_dynamic_symbol): When initialising weak aliases,
don't uselessly copy non_got_ref. Clear dyn_relocs instead if
strong symbol is allocated in dynbss. Tidy comments.
I did this for powerpc64 a while ago. Not moving weak symbol
dyn_relocs to the strong alias makes for a much simpler test for
dynamic relocs in relocate_section.
This patch implements the change for powerpc and hppa. Other targets
could benefit from similar changes.
* elf32-hppa.c (pc_dynrelocs): Define.
(elf32_hppa_copy_indirect_symbol): Don't copy dyn_relocs to weakdefs.
(alias_readonly_dynrelocs): New function.
(elf32_hppa_adjust_dynamic_symbol): Don't clear non_got_ref to
indicate dyn_relocs should be discarded, discard them here.
Use alias_readonly_dynrelocs.
(allocate_dynrelocs): Don't test or clear non_got_ref.
(elf32_hppa_relocate_section): Simplify test for dynamic relocs.
* elf32-ppc.c (ppc_elf_copy_indirect_symbol): Don't copy dyn_relocs
to weakdefs.
(alias_readonly_dynrelocs, pc_dynrelocs): New functions.
(ppc_elf_adjust_dynamic_symbol): Don't clear non_got_ref to
indicate dyn_relocs should be discarded, discard them here.
Use alias_readonly_dynrelocs.
(allocate_dynrelocs): Don't test or clear non_got_ref.
(ppc_elf_relocate_section): Simplify test for dynamic relocs.
This makes the elf_link_hash_entry weakdef field, currently used to
point from a weak symbol to a strong alias, a circular list so that
all aliases can be found from any of them. A new flag, is_weakalias,
distinguishes the weak symbol from a strong alias, and is used in all
places where we currently test u.weakdef != NULL.
With the original u.weakdef handling it was possible to have two or
more weak symbols pointing via u.weakdef to a strong definition.
Obviously that situation can't map to a circular list; One or more of
the weak symbols must point at another weak alias rather than the
strong definition. To handle that, I've added an accessor function to
return the strong definition.
* elf-bfd.h (struct elf_link_hash_entry): Add is_weakalias.
Rename u.weakdef to u.alias and update comment.
(weakdef): New static inline function.
* elflink.c (bfd_elf_record_link_assignment) Test is_weakalias
rather than u.weakdef != NULL, and use weakdef function.
(_bfd_elf_adjust_dynamic_symbol): Likewise.
(_bfd_elf_fix_symbol_flags): Likewise. Clear is_weakalias on
all aliases if def has been overridden in a regular object, not
u.weakdef.
(elf_link_add_object_symbols): Delete new_weakdef flag. Test
is_weakalias and use weakdef. Set is_weakalias and circular
u.alias. Update comments.
(_bfd_elf_gc_mark_rsec): Test is_weakalias rather than
u.weakdef != NULL and use weakdef function.
* elf-m10300.c (_bfd_mn10300_elf_adjust_dynamic_symbol): Test
is_weakalias rather than u.weakdef != NULL and use weakdef
function. Assert that def is strong defined.
* elf32-arc.c (elf_arc_adjust_dynamic_symbol): Likewise.
* elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Likewise.
* elf32-bfin.c (elf32_bfinfdpic_adjust_dynamic_symbol): Likewise.
(bfin_adjust_dynamic_symbol): Likewise.
* elf32-cr16.c (_bfd_cr16_elf_adjust_dynamic_symbol): Likewise.
* elf32-cris.c (elf_cris_adjust_dynamic_symbol): Likewise.
* elf32-frv.c (elf32_frvfdpic_adjust_dynamic_symbol): Likewise.
* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol): Likewise.
* elf32-i370.c (i370_elf_adjust_dynamic_symbol): Likewise.
* elf32-lm32.c (lm32_elf_adjust_dynamic_symbol): Likewise.
* elf32-m32r.c (m32r_elf_adjust_dynamic_symbol): Likewise.
* elf32-m68k.c (elf_m68k_adjust_dynamic_symbol): Likewise.
* elf32-metag.c (elf_metag_adjust_dynamic_symbol): Likewise.
* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Likewise.
* elf32-nds32.c (nds32_elf_adjust_dynamic_symbol): Likewise.
* elf32-nios2.c (nios2_elf32_adjust_dynamic_symbol): Likewise.
* elf32-or1k.c (or1k_elf_adjust_dynamic_symbol): Likewise.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Likewise.
* elf32-s390.c (elf_s390_adjust_dynamic_symbol): Likewise.
* elf32-score.c (s3_bfd_score_elf_adjust_dynamic_symbol): Likewise.
* elf32-score7.c (s7_bfd_score_elf_adjust_dynamic_symbol): Likewise.
* elf32-sh.c (sh_elf_adjust_dynamic_symbol): Likewise.
* elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol): Likewise.
* elf32-tilepro.c (tilepro_elf_gc_mark_hook): Likewise.
(tilepro_elf_adjust_dynamic_symbol): Likewise.
* elf32-vax.c (elf_vax_adjust_dynamic_symbol): Likewise.
* elf32-xtensa.c (elf_xtensa_adjust_dynamic_symbol): Likewise.
* elf64-alpha.c (elf64_alpha_adjust_dynamic_symbol): Likewise.
* elf64-hppa.c (elf64_hppa_adjust_dynamic_symbol): Likewise.
* elf64-ia64-vms.c (elf64_ia64_adjust_dynamic_symbol): Likewise.
* elf64-ppc.c (ppc64_elf_gc_mark_hook): Likewise.
(ppc64_elf_adjust_dynamic_symbol): Likewise.
* elf64-s390.c (elf_s390_adjust_dynamic_symbol): Likewise.
* elf64-sh64.c (sh64_elf64_adjust_dynamic_symbol): Likewise.
* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol): Likewise.
* elfnn-ia64.c (elfNN_ia64_adjust_dynamic_symbol): Likewise.
* elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol): Likewise.
* elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol): Likewise.
* elfxx-sparc.c (_bfd_sparc_elf_gc_mark_hook): Likewise.
(_bfd_sparc_elf_adjust_dynamic_symbol): Likewise.
* elfxx-tilegx.c (tilegx_elf_gc_mark_hook): Likewise.
(tilegx_elf_adjust_dynamic_symbol): Likewise.
* elfxx-x86.c (_bfd_x86_elf_adjust_dynamic_symbol): Likewise.
This patch was aimed at a FIXME in elf32-hppa.c, the ludicrous and
confusing fact that non_got_ref after adjust_dynamic_relocs in that
backend means precisely the inverse of what it means before
adjust_dynamic_relocs. Before, when non_got_ref is set it means there
are dynamic relocs, after, if non_got_ref is clear it means "keep
dynamic relocs" and later, "has dynamic relocs". There is a reason
why it was done that way.. Some symbols that may have dynamic
relocations pre-allocated in check_relocs turn out to not be dynamic,
and then are not seen by the backend adjust_dynamic_symbols. We want
those symbols to lose their dynamic relocs when non-pic, so it's handy
that non_got_ref means the opposite after adjust_dynamic_relocs. But
it's really confusing.
Most other targets, like ppc32, don't always set non_got_ref on
non-GOT references that have dynamic relocations. This is because the
primary purpose of non_got_ref before adjust_dynamic_relocs is to flag
symbols that might need to be copied to .dynbss, and there are
relocation types that may require dyn_relocs but clearly cannot have
symbols copied into .dynbss, for example, TLS relocations.
Why do we need a flag after adjust_dynamic_relocs to say "keep
dynamic relocations"? Well, you can discard most unwanted dyn_relocs
in the backend adjust_dynamic_relocs, and for those symbols that
aren't seen by the backend adjust_dynamic_relocs, in
allocate_dynrelocs based on a flag set by adjust_dynamic relocs,
dynamic_adjusted. That doesn't solve all our difficulties though.
relocate_section needs to know whether a symbol has dyn_relocs, and
many targets transfer dyn_relocs to a weakdef if the symbol has one.
The transfer means relocate_section can't test dyn_relocs itself and
the weakdef field has been overwritten by that time. So non_got_ref
is used to flag "this symbol has dynamic relocations" for
relocate_section.
Confused still? Well, let's hope the comments I've added help clarify
things.. The patch also fixes a case where we might wrongly emit
dynamic relocations in an executable for common and undefined symbols.
* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol): Set non_got_ref
to keep dyn_relocs, clear to discard. Comment.
(allocate_dynrelocs): Always clear non_got_ref when clearing
dyn_relocs in non-pic case. Invert non_got_ref test. Also test
dynamic_adjusted and ELF_COMMON_DEF_P. Move code deleting
dyn_relocs on undefined syms to handle for non-pic too.
(elf32_hppa_relocate_section): Simplify test for non-pic dyn relocs.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Set non_got_ref
to keep dyn_relocs, clear to discard. Comment.
(allocate_dynrelocs): Always clear non_got_ref when clearing
dyn_relocs in non-pic case. Invert non_got_ref test. Also test
dynamic_adjusted and ELF_COMMON_DEF_P. Move code deleting
dyn_relocs on undefined syms to handle for non-pic too.
(ppc_elf_relocate_section): Simplify test for non-pic dyn relocs.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol): Discard
dyn_relocs here. Don't bother setting non_got_ref. Comment.
(allocate_dynrelocs): Delete special handling of non-pic ELFv2
ifuncs. Move code deleting dyn_relocs on undefined symbols to
handle for non-pic too. Don't test non_got_ref. Do test
dynamic_adjusted and ELF_COMMON_DEF_P.
This patch fixes various problems with TLS relocations.
1) Report an error if a symbol has both TLS and normal GOT entries.
2) The GOT entry size calculation was obscure and made use of the fact
that a symbol shouldn't have both normal and TLS GOT entries.
3) The second word of a GD GOT entry sometimes omitted a dynamic
reloc, which was fine except that doing so makes it impossible for
ld.so to differentiate GD and LD entries. Also, a NONE reloc was
emitted.
4) Unnecessary relocs were emitted for GOT entries.
5) GOT relocs didn't take note of UNDEFWEAK_NO_DYNAMIC_RELOC.
* elf32-hppa.c (enum _tls_type): Move.
(struct elf32_hppa_link_hash_entry): Make tls_type a bitfield.
(elf32_hppa_check_relocs): Set DF_STATIC_TLS only for shared libraries.
Tidy tls_type handling. Set symbol tls_type for GOT_TLS_LDM too.
(got_entries_needed, got_relocs_needed): New functions.
(allocate_dynrelocs): Use them.
(elf32_hppa_size_dynamic_sections): Likewise.
(elf32_hppa_relocate_section): Delete bogus FIXME. Formatting.
Correct code emitting relocs on GD/IE got entries. Report an
error when a symbol has both normal and TLS GOT relocs.
gcc -mfast-indirect-calls emits a function pointer initialization
without a P% (plabel) modifier. ld does not create the necessary
dynamic relocations for this to work. It turns out that the problem
is caused by the non_got_ref symbol flag. This flag is set for
non-pic by check_relocs to indicate that the symbol might need copy
relocations or dynamic relocations. Later, the backend
adjust_dynamic_symbol clears the flag to indicate dynamic relocations
are needed, but leaves it set when copy relocations were created. The
inversion in meaning is insane, but it's that way because the backend
adjust_dynamic_symbol function doesn't get to look at all symbols..
Anyway, the insanity works for non-function symbols. However, the
flag is left set on any function symbol with a dynamic relocation.
This patch fixes the non_got_ref handling for function symbols, adds
-z nocopyreloc for hppa-elf, reports where textrel occurs, and expands
comments. The check_relocs change just stops creation of dyn_relocs
we always threw away later.
PR 22394
* elf32-hppa.c (elf32_hppa_check_relocs): Don't create dyn_relocs
for plabels when non-pic.
(maybe_set_textrel): New function.
(readonly_dynrelocs): Move and rewrite.
(elf32_hppa_adjust_dynamic_symbol): Use it. Don't create copy
relocs when def_regular or -z nocopyreloc. Handle non_got_ref
for functions. Expand non_got_ref comments.
(elf32_hppa_size_dynamic_sections): Use maybe_set_textrel.
Adds UNDEFWEAK_NO_DYNAMIC_RELOC in the rest of places needed in this
file, reduces dynamic relocations in a number of cases, and removes
some bogus code that was attempting to handle dynamic common symbols
specially.
PR 22269
* elf32-hppa.c (elf32_hppa_check_relocs): Move SEC_ALLOC test to
ensure non_got_ref is not set due to debug references.
(elf32_hppa_adjust_dynamic_symbol): Tidy plabel handling. Use
SYMBOL_CALLS_LOCAL and UNDEFWEAK_NO_DYNAMIC_RELOC when determining
need for a plt entry.
(allocate_dynrelocs): Similarly for got entries. Tidy code discarding
dynamic relocs when pic. Remove bogus code attempting to handle
commons.
(elf32_hppa_relocate_section): Similarly. Delete resolved_to_zero
and simplify.
(elf32_hppa_finish_dynamic_symbol): Use UNDEFWEAK_NO_DYNAMIC_RELOC
and SYMBOL_REFERENCES_LOCAL in GOT handling.
polyml produces object files with the wrong OS/ABI for hppa-linux.
This, along with the fact that elf32-hppa.c is using the strictest
backend relocs_compatible, results in wrong merging of ELF symbols.
So, remove the relocs_compatible check in _bfd_elf_merge_symbol.
_bfd_elf_merge_symbol is only called nowadays from within blocks
protected by is_elf_hash_table, so "we are doing an ELF link" as the
removed comment says, is true.
Also relax relocs_compatible for hppa and powerpc. relocs_compatible
is used for more than just merging symbols, as the name suggests.
This allows objects that are in fact reasonably compatible to be
linked.
PR 22300
* elflink.c (_bfd_elf_merge_symbol): Remove relocs_compatible check.
* elf32-hppa.c (elf_backend_relocs_compatible): Define.
* elf32-ppc.c (elf_backend_relocs_compatible): Define.
* elf64-ppc.c (elf_backend_relocs_compatible): Define.
Don't generate dynamic relocation against weak undefined symbol if it
is resolved to zero. FIXME: UNDEFWEAK_NO_DYNAMIC_RELOC may need to be
checked in more places.
PR ld/22269
* elf32-hppa.c (ensure_undef_dynamic): Don't make undefined
symbol dynamic if UNDEFWEAK_NO_DYNAMIC_RELOC is true.
(allocate_dynrelocs): Discard dynamic relocations if
UNDEFWEAK_NO_DYNAMIC_RELOC is true.
(elf32_hppa_relocate_section): Don't generate dynamic
relocation if UNDEFWEAK_NO_DYNAMIC_RELOC is true.
..if they have dynamic relocs. An undefined symbol in a PIC object
that finds no definition ought to become dynamic in order to support
--allow-shlib-undefined, but there is nothing in the generic ELF
linker code to do this if the reference isn't via the GOT or PLT. (An
initialized function pointer is an example.) So it falls to backend
code to ensure the symbol is made dynamic.
PR 21988
* elf64-ppc.c (ensure_undef_dynamic): Rename from
ensure_undefweak_dynamic. Handle undefined too.
* elf32-ppc.c (ensure_undef_dynamic): Likewise.
* elf32-hppa.c (ensure_undef_dynamic): Likewise.
(allocate_dynrelocs): Discard undefined non-default visibility
relocs first. Make undefined syms dynamic. Tidy goto.
The base bfd_link_hash_table works fine here, the only thing to watch
out for is to only set elf_gp if the output is ELF.
bfd/
* elf32-hppa.c (elf32_hppa_set_gp): Don't require an
hppa_link_hash_table.
ld/
* testsuite/ld-unique/pr21529.d: Don't xfail hppa.
I'd made this dynamic section read-only so a flag test distinguished
it from .dynbss, but like any other .data.rel.ro section it really
should be marked read-write. (It is read-only after relocation, not
before.) When using the standard linker scripts this usually doesn't
matter since the output section is among other read-write sections and
not page aligned. However, it might matter in the extraordinary case
of the dynamic section being the only .data.rel.ro section with the
output section just happening to be page aligned and a multiple of a
page in size. In that case the output section would be read-only, and
live it its own read-only PT_LOAD segment, which is incorrect.
* elflink.c (_bfd_elf_create_dynamic_sections): Don't make
dynamic .data.rel.ro read-only.
* elf32-arm.c (elf32_arm_finish_dynamic_symbol): Compare section
rather than section flags when deciding where copy reloc goes.
* elf32-cris.c (elf_cris_finish_dynamic_symbol): Likewise.
* elf32-hppa.c (elf32_hppa_finish_dynamic_symbol): Likewise.
* elf32-i386.c (elf_i386_finish_dynamic_symbol): Likewise.
* elf32-metag.c (elf_metag_finish_dynamic_symbol): Likewise.
* elf32-microblaze.c (microblaze_elf_finish_dynamic_symbol): Likewise.
* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol): Likewise.
* elf32-or1k.c (or1k_elf_finish_dynamic_symbol): Likewise.
* elf32-ppc.c (ppc_elf_finish_dynamic_symbol): Likewise.
* elf32-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
* elf32-tic6x.c (elf32_tic6x_finish_dynamic_symbol): Likewise.
* elf32-tilepro.c (tilepro_elf_finish_dynamic_symbol): Likewise.
* elf64-ppc.c (ppc64_elf_finish_dynamic_symbol): Likewise.
* elf64-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
* elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Likewise.
* elfnn-aarch64.c (elfNN_aarch64_finish_dynamic_symbol): Likewise.
* elfnn-riscv.c (riscv_elf_finish_dynamic_symbol): Likewise.
* elfxx-mips.c (_bfd_mips_vxworks_finish_dynamic_symbol): Likewise.
* elfxx-sparc.c (_bfd_sparc_elf_finish_dynamic_symbol): Likewise.
* elfxx-tilegx.c (tilegx_elf_finish_dynamic_symbol): Likewise.
I misunderstood the hppa alias problem. File offsets of segments need
to be such that no page is mapped twice with different permissions.
(Which still seems to me like something the kernel could fix, but
anyhow, this is not so difficult to achieve in ld.)
PR 21000
bfd/
* elf-bfd.h (struct elf_backend_data): Add no_page_alias.
* elfxx-target.h (elf_backend_no_page_alias): Define.
(elfNN_bed): Init new field.
* elf.c (assign_file_positions_for_load_sections): If no_page_alias
ensure PT_LOAD segment starts on a new page.
* elf32-hppa.c (elf_backend_no_page_alias): Define.
ld/
* testsuite/ld-elf/loadaddr1.d: Adjust for hppa file offsets.
* testsuite/ld-elf/loadaddr2.d: Likewise.
* testsuite/ld-elf/loadaddr3a.d: Likewise.
* testsuite/ld-scripts/rgn-at5.d: Likewise.
This fixes a long-standing hppa bug seen when generating PIEs, and I
think possible to trigger with forced local symbols in shared
libraries. Not allocating enough space for PLT relocs results in ld
writing outside of the buffer.
PR 21132
* elf32-hppa.c (allocate_plt_static): Allocate space for relocs
if pic.
Fixes: tmpdir/pr14525: symbol lookup error: tmpdir/pr14525: undefined
symbol: __executable_start
FAIL: PIE PR ld/14525
* elf32-hppa.c (ensure_undef_weak_dynamic): New function.
(allocate_plt_static, allocate_dynrelocs): Use it.
A while ago HJ fixed PR ld/18720 with commit 6e33951ed, which, among
other things, modified _bfd_elf_link_hash_copy_indirect to not copy
ref_dynamic, ref_regular, ref_regular_nonweak, non_got_ref, needs_plt
and pointer_equality_needed when setting up an indirect non-versioned
symbol pointing to a non-default versioned symbol. I didn't notice at
the time, but the pr18720 testcase fails on hppa-linux with
"internal error, aborting at binutils-gdb-2.28/bfd/elf32-hppa.c:3933
in elf32_hppa_relocate_section".
Now hppa-linux creates entries in the plt even for local functions, if
they are referenced using plabel (function pointer) relocations. So
needs_plt is set for foo when processing pr18720a.o. When the aliases
in pr28720b.o are processed, we get an indirection from foo to
foo@FOO, but don't copy needs_plt. Since foo@FOO is the "real" symbol
that is used after that point, no plt entry is made for foo and we
bomb when relocating the plabel.
As shown by the hppa-linux scenario, needs_plt should be copied even
for non-default versioned symbols. I believe all of the others ought
to be copied too, with the exception of ref_dynamic. Not copying
ref_dynamic is right because if a shared lib references "foo" it
should not be satisfied by any non-default version "foo@FOO".
* elflink.c (_bfd_elf_link_hash_copy_indirect): Only omit
copying one flag, ref_dynamic, when versioned_hidden.
* elf64-ppc.c (ppc64_elf_copy_indirect_symbol): Likewise.
* elf32-hppa.c (elf32_hppa_copy_indirect_symbol): Use same
logic for copying weakdef flags. Copy plabel flag and merge
tls_type.
* elf32-i386.c (elf_i386_copy_indirect_symbol): Use same logic
for copying weakdef flags.
* elf32-ppc.c (ppc_elf_copy_indirect_symbol): Likewise.
* elf32-s390.c (elf_s390_copy_indirect_symbol): Likewise.
* elf32-sh.c (sh_elf_copy_indirect_symbol): Likewise.
* elf64-s390.c (elf_s390_copy_indirect_symbol): Likewise.
* elfnn-ia64.c (elfNN_ia64_hash_copy_indirect): Likewise.
* elf64-x86-64.c (elf_x86_64_copy_indirect_symbol): Likewise.
Simplify.
Variables defined in shared libraries are copied into an executable's
.bss section when code in the executable is non-PIC and thus would
require dynamic text relocations to access the variable directly in
the shared library. Recent x86 toolchains also copy variables into
the executable to gain a small speed improvement.
The problem is that if the variable was originally read-only, the copy
in .bss is writable, potentially opening a security hole. This patch
cures that problem by putting the copy in a section that becomes
read-only after ld.so relocation, provided -z relro is in force.
The patch also fixes a microblaze linker segfault on attempting to
use dynamic bss variables.
bfd/
PR ld/20995
* elf-bfd.h (struct elf_link_hash_table): Add sdynrelro and
sreldynrelro.
(struct elf_backend_data): Add want_dynrelro.
* elfxx-target.h (elf_backend_want_dynrelro): Define.
(elfNN_bed): Update initializer.
* elflink.c (_bfd_elf_create_dynamic_sections): Create
sdynrelro and sreldynrelro sections.
* elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Place variables
copied into the executable from read-only sections into sdynrelro.
(elf32_arm_size_dynamic_sections): Handle sdynrelro.
(elf32_arm_finish_dynamic_symbol): Select sreldynrelro for
dynamic relocs in sdynrelro.
(elf_backend_want_dynrelro): Define.
* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol)
(elf32_hppa_size_dynamic_sections, elf32_hppa_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-i386.c (elf_i386_adjust_dynamic_symbol)
(elf_i386_size_dynamic_sections, elf_i386_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-metag.c (elf_metag_adjust_dynamic_symbol)
(elf_metag_size_dynamic_sections, elf_metag_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol)
(microblaze_elf_size_dynamic_sections)
(microblaze_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol)
(nios2_elf32_adjust_dynamic_symbol)
(nios2_elf32_size_dynamic_sections)
(elf_backend_want_dynrelro): As above.
* elf32-or1k.c (or1k_elf_finish_dynamic_symbol)
(or1k_elf_adjust_dynamic_symbol, or1k_elf_size_dynamic_sections)
(elf_backend_want_dynrelro): As above.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol)
(ppc_elf_size_dynamic_sections, ppc_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-s390.c (elf_s390_adjust_dynamic_symbol)
(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol)
(elf32_tic6x_size_dynamic_sections)
(elf32_tic6x_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf32-tilepro.c (tilepro_elf_adjust_dynamic_symbol)
(tilepro_elf_size_dynamic_sections)
(tilepro_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol)
(ppc64_elf_size_dynamic_sections, ppc64_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-s390.c (elf_s390_adjust_dynamic_symbol)
(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elf64-x86-64.c (elf_x86_64_adjust_dynamic_symbol)
(elf_x86_64_size_dynamic_sections)
(elf_x86_64_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol)
(elfNN_aarch64_size_dynamic_sections)
(elfNN_aarch64_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol)
(riscv_elf_size_dynamic_sections, riscv_elf_finish_dynamic_symbol)
(elf_backend_want_dynrelro): As above.
* elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol)
(_bfd_mips_elf_size_dynamic_sections)
(_bfd_mips_vxworks_finish_dynamic_symbol): As above.
* elfxx-sparc.c (_bfd_sparc_elf_adjust_dynamic_symbol)
(_bfd_sparc_elf_size_dynamic_sections)
(_bfd_sparc_elf_finish_dynamic_symbol): As above.
* elfxx-tilegx.c (tilegx_elf_adjust_dynamic_symbol)
(tilegx_elf_size_dynamic_sections)
(tilegx_elf_finish_dynamic_symbol): As above.
* elf32-mips.c (elf_backend_want_dynrelro): Define.
* elf64-mips.c (elf_backend_want_dynrelro): Define.
* elf32-sparc.c (elf_backend_want_dynrelro): Define.
* elf64-sparc.c (elf_backend_want_dynrelro): Define.
* elf32-tilegx.c (elf_backend_want_dynrelro): Define.
* elf64-tilegx.c (elf_backend_want_dynrelro): Define.
* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Tidy.
(microblaze_elf_size_dynamic_sections): Handle sdynbss.
* elf32-nios2.c (nios2_elf32_size_dynamic_sections): Make use
of linker shortcuts to dynamic sections rather than comparing
names. Correctly set "got" flag.
ld/
PR ld/20995
* testsuite/ld-arm/farcall-mixed-app-v5.d: Update to suit changed
stub hash table traversal caused by section id increment. Accept
the previous output too.
* testsuite/ld-arm/farcall-mixed-app.d: Likewise.
* testsuite/ld-arm/farcall-mixed-lib-v4t.d: Likewise.
* testsuite/ld-arm/farcall-mixed-lib.d: Likewise.
* testsuite/ld-elf/pr20995a.s, * testsuite/ld-elf/pr20995b.s,
* testsuite/ld-elf/pr20995.r: New test.
* testsuite/ld-elf/elf.exp: Run it.
Alan Modra
John David Anglin
H.J. Lu
Nick Clifton