This patch fixes a few linker crashes due to TLS code reaching an assert when it
shouldn't.
The first scenario is with weak TLS symbols that remain weak during linking. In
this case the mid-end would not have seen a TLS symbol and so wouldn't have
allocated the TLS section. We currently assert here and the linker crashes with
a not very useful message.
This patch changes this to return the value 0 for the TLS symbol in question
emulating what lld and gold and other BFD targets do. However because weak TLS
is implementation defined and we don't define any behavior for it I also emit a
warning to the user to inform them of such.
Secondly when a strong TLS reference is undefined. The linker crashes even after
it correctly reported that there is an undefined reference. This changes it so
that it gracefully exits and reports a useful error.
bfd/ChangeLog:
PR ld/24601
* elfnn-aarch64.c (aarch64_relocate): Handle weak TLS and undefined TLS.
Also Pass input_bfd to _bfd_aarch64_elf_resolve_relocation.
* elfxx-aarch64.c (_bfd_aarch64_elf_resolve_relocation): Use it.
* elfxx-aarch64.h (_bfd_aarch64_elf_resolve_relocation): Emit warning
for weak TLS.
ld/ChangeLog:
PR ld/24601
* testsuite/ld-aarch64/aarch64-elf.exp (undef-tls, weak-tls): New.
* testsuite/ld-aarch64/undef-tls.d: New test.
* testsuite/ld-aarch64/undef-tls.s: New test.
* testsuite/ld-aarch64/weak-tls.d: New test.
* testsuite/ld-aarch64/weak-tls.s: New test.
If the new GNU property section was being created by the linker
(this will happen only if none of the inputs have any GNU property
section but the command line to the linker forces a bti with
--force-bti), the alignment of the section and hence the program
header of PT_GNU_PROPERTY type was not being set correctly. This
patch fixes this issue.
bfd/ChangeLog:
2019-06-06 Sudakshina Das <sudi.das@arm.com>
* elfxx-aarch64.c (_bfd_aarch64_elf_link_setup_gnu_properties): Set
alignment of the new gnu property section.
ld/ChangeLog:
2019-06-06 Sudakshina Das <sudi.das@arm.com>
* testsuite/ld-aarch64/aarch64-elf.exp: Add new tests.
* testsuite/ld-aarch64/property-bti-pac4-a.d: New test.
* testsuite/ld-aarch64/property-bti-pac4-b.d: New test.
* testsuite/ld-aarch64/property-bti-pac4.s: New test.
The AArch64 linker option to turn on BTI (--force-bti) warns in case there are
input objects which have a missing GNU NOTE section for BTI. This patch is trying
to improve the warnings that come out.
In order to do so, I propose adding a new argument to elf_merge_gnu_properties
and the backend function merge_gnu_properties. This new argument makes sure
that we now pass both the objects along with the properties to which they
belong to. The x86 backend function has also been updated to match this
change.
*** bfd/ChangeLog ***
2019-03-21 Sudakshina Das <sudi.das@arm.com>
* elf-bfd.h (struct elf_backend_data): Add argument to
merge_gnu_properties.
* elf-properties.c (elf_merge_gnu_properties): Add argument to
itself and while calling bed->merge_gnu_properties.
(elf_merge_gnu_property_list): Update the calls for
elf_merge_gnu_properties.
* elfnn-aarch64.c (elfNN_aarch64_merge_gnu_properties): Update handling
of --force-bti warning and add argument.
* elfxx-aarch64.c (_bfd_aarch64_elf_link_setup_gnu_properties): Add
warning.
* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Add argument.
* elfxx-x86.h (_bfd_x86_elf_merge_gnu_properties): Likewise in
declaration.
*** ld/ChangeLog ***
2019-03-21 Sudakshina Das <sudi.das@arm.com>
* testsuite/ld-aarch64/aarch64-elf.exp: Add new test.
* testsuite/ld-aarch64/bti-plt-1.s: Add .ifdef for PAC note section.
* testsuite/ld-aarch64/bti-plt-6.d: Update warning.
* testsuite/ld-aarch64/bti-plt-7.d: Likewise.
* testsuite/ld-aarch64/bti-warn.d: New test.
This patch add support for elf_backend_fixup_gnu_properties for GNU
property support for AArch64. The new AArch64 specific definition
_bfd_aarch64_elf_link_fixup_gnu_properties goes through the property
list to find AArch64 type properties and removes the properties that
are marked as "property_remove".
*** bfd/ChangeLog ***
2019-03-20 Sudakshina Das <sudi.das@arm.com>
* elfxx-aarch64.c (_bfd_aarch64_elf_link_fixup_gnu_properties): Define.
* elfxx-aarch64.h (_bfd_aarch64_elf_link_fixup_gnu_properties): Declare.
(elf_backend_fixup_gnu_properties): Define for AArch64.
This is part of the patch series to add support for BTI and
PAC in AArch64 linker.
This patch implements the following:
1) This extends in the gnu property support in the linker for
AArch64 by defining backend hooks for elf_backend_setup_gnu_properties,
elf_backend_merge_gnu_properties and elf_backend_parse_gnu_properties.
2) It defines AArch64 specific GNU property
GNU_PROPERTY_AARCH64_FEATURE_1_AND and 2 bit for BTI and PAC in it.
3) It also adds support in readelf.c to read and print these new
GNU properties in AArch64.
All these are made according to the new AArch64 ELF ABI
https://developer.arm.com/docs/ihi0056/latest/elf-for-the-arm-64-bit-architecture-aarch64-abi-2018q4
*** bfd/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elf-properties.c (_bfd_elf_link_setup_gnu_properties): Exclude
linker created inputs from merge.
* elfnn-aarch64.c (struct elf_aarch64_obj_tdata): Add field for
GNU_PROPERTY_AARCH64_FEATURE_1_AND properties.
(elfNN_aarch64_link_setup_gnu_properties): New.
(elfNN_aarch64_merge_gnu_properties): New.
(elf_backend_setup_gnu_properties): Define for AArch64.
(elf_backend_merge_gnu_properties): Likewise.
* elfxx-aarch64.c (_bfd_aarch64_elf_link_setup_gnu_properties): Define.
(_bfd_aarch64_elf_parse_gnu_properties): Define.
(_bfd_aarch64_elf_merge_gnu_properties): Define.
* elfxx-aarch64.h (_bfd_aarch64_elf_link_setup_gnu_properties): Declare.
(_bfd_aarch64_elf_parse_gnu_properties): Declare.
(_bfd_aarch64_elf_merge_gnu_properties): Declare.
(elf_backend_parse_gnu_properties): Define for AArch64.
*** binutils/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* readelf.c (decode_aarch64_feature_1_and): New.
(print_gnu_property_note): Add case for AArch64 gnu notes.
*** include/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* elf/common.h (GNU_PROPERTY_AARCH64_FEATURE_1_AND): New.
(GNU_PROPERTY_AARCH64_FEATURE_1_BTI): New.
(GNU_PROPERTY_AARCH64_FEATURE_1_PAC): New.
*** ld/ChangeLog ***
2019-03-13 Sudakshina Das <sudi.das@arm.com>
* NEWS: Document GNU_PROPERTY_AARCH64_FEATURE_1_BTI and
GNU_PROPERTY_AARCH64_FEATURE_1_PAC.
* testsuite/ld-aarch64/aarch64-elf.exp: Add run commands for new tests.
* testsuite/ld-aarch64/property-bti-pac1.d: New test.
* testsuite/ld-aarch64/property-bti-pac1.s: New test.
* testsuite/ld-aarch64/property-bti-pac2.d: New test.
* testsuite/ld-aarch64/property-bti-pac2.s: New test.
* testsuite/ld-aarch64/property-bti-pac3.d: New test.
Fixes a number of build errors like the following
.../elf32-arm.c: In function 'elf32_arm_nabi_write_core_note':
.../elf32-arm.c:2177: error: #pragma GCC diagnostic not allowed inside functions
.../elf32-arm.c:2186: error: #pragma GCC diagnostic not allowed inside functions
See the comment in diagnostics.h.
include/
* diagnostics.h: Comment on macro usage.
bfd/
* elf32-arm.c (elf32_arm_nabi_write_core_note): Don't use
DIAGNOTIC_PUSH and DIAGNOSTIC_POP unconditionally.
* elf32-ppc.c (ppc_elf_write_core_note): Likewise.
* elf32-s390.c (elf_s390_write_core_note): Likewise.
* elf64-ppc.c (ppc64_elf_write_core_note): Likewise.
* elf64-s390.c (elf_s390_write_core_note): Likewise.
* elfxx-aarch64.c (_bfd_aarch64_elf_write_core_note): Likewise.
This patch is aimed at silencing gcc8 -Wstringop-truncation warnings.
Unfortunately adding __attribute__ ((__nonstring)) doesn't work in a
number of the places patched here, (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643) so if you have
recent glibc headers installed you'll need to configure binutils with
--disable-werror to compile using gcc8 or gcc9.
include/
* ansidecl.h: Import from gcc.
* coff/internal.h (struct internal_scnhdr): Add ATTRIBUTE_NONSTRING
to s_name.
(struct internal_syment): Add ATTRIBUTE_NONSTRING to _n_name.
bfd/
* elf-linux-core.h (struct elf_external_linux_prpsinfo32_ugid32),
(struct elf_external_linux_prpsinfo32_ugid16),
(struct elf_external_linux_prpsinfo64_ugid32),
(struct elf_external_linux_prpsinfo64_ugid16): Add ATTRIBUTE_NONSTRING
to pr_fname and pr_psargs fields. Remove GCC diagnostic pragmas.
Move comment to..
* elf.c (elfcore_write_prpsinfo): ..here. Indent nested preprocessor
directives.
* elf32-arm.c (elf32_arm_nabi_write_core_note): Add ATTRIBUTE_NONSTRING
to data.
* elf32-ppc.c (ppc_elf_write_core_note): Likewise.
* elf32-s390.c (elf_s390_write_core_note): Likewise.
* elf64-s390.c (elf_s390_write_core_note): Likewise.
* elfxx-aarch64.c (_bfd_aarch64_elf_write_core_note): Likewise.
* elf64-x86-64.c (elf_x86_64_write_core_note): Add GCC diagnostic
pragmas.
* peXXigen.c (_bfd_XXi_swap_scnhdr_out): Use strnlen to avoid
false positive gcc-8 warning.
gas/
* config/obj-evax.c (shorten_identifier): Use memcpy in place
of strncpy.
* config/obj-macho.c (obj_mach_o_make_or_get_sect): Ensure
segname and sectname fields are NUL terminated.
This patch adds the following relocation support into binutils bfd linker.
BFD_RELOC_AARCH64_TLSLE_LDST16_TPREL_LO12,
BFD_RELOC_AARCH64_TLSLE_LDST16_TPREL_LO12_NC,
BFD_RELOC_AARCH64_TLSLE_LDST32_TPREL_LO12,
BFD_RELOC_AARCH64_TLSLE_LDST32_TPREL_LO12_NC,
BFD_RELOC_AARCH64_TLSLE_LDST64_TPREL_LO12,
BFD_RELOC_AARCH64_TLSLE_LDST64_TPREL_LO12_NC,
BFD_RELOC_AARCH64_TLSLE_LDST8_TPREL_LO12,
BFD_RELOC_AARCH64_TLSLE_LDST8_TPREL_LO12_NC.
Those relocations includes both ip64 and ilp32 variant.
There are quite a few duplicated code supporting several GP based
relocation types. They are:
BFD_RELOC_AARCH64_LD64_GOTOFF_LO15
BFD_RELOC_AARCH64_MOVW_GOTOFF_G0_NC
BFD_RELOC_AARCH64_MOVW_GOTOFF_G1
These relocation types are supposed to be used for large memory model PIC/pic
mode under which we will have an initialized GP register points to the base of
GOT table, then these relocations are supposed to put the distance between GOT
entry and GOT table base address into the related instructions.
So, the parameters required to calculate the relocation should be the same as
BFD_RELOC_AARCH64_LD64_GOTPAGE_LO15 etc, all of them are require the GOT entry
address and GOT table base address to perform the relocation.
This patch has removed those duplicated code when handling above listed
relocation types, grouped them with others as relocation types that are
require GOT table base address during performing relocation, reused the
existed GOT handling code.
The relocation calculation for these types before and after this patch should be
identical.
bfd/
* elfnn-aarch64.c (aarch64_relocation_aginst_gp_p): New function.
(elfNN_aarch64_final_link_relocate): Delete duplicated code for
BFD_RELOC_AARCH64_LD64_GOTOFF_LO15, BFD_RELOC_AARCH64_MOVW_GOTOFF_G0_NC,
BFD_RELOC_AARCH64_MOVW_GOTOFF_G1.
* elfxx-aarch64.c (_bfd_aarch64_elf_resolve_relocation): Optimize the
support for them.
Since the backend elf_add_symbol_hook isn't called on local symbols,
the EI_OSABI field isn't to ELFOSABI_GNU where are local IFUNC symbols.
This patch changes the x86 backends to set has_gnu_symbols if there are
relocations against IFUNC symbols. Other backends with IFUNC support
may need a similar change.
This patch also changes the type of has_gnu_symbols from bfd_boolean to
enum elf_gnu_symbols.
bfd/
PR ld/18815
* elf-bfd.h (elf_gnu_symbols): New enum.
(elf_obj_tdata): Use elf_gnu_symbols on has_gnu_symbols.
* elf-s390-common.c (elf_s390_add_symbol_hook): Set
has_gnu_symbols to elf_gnu_symbol_any.
* elf32-arm.c (elf32_arm_add_symbol_hook): Likewise.
* elf32-m68k.c (elf_m68k_add_symbol_hook): Likewise.
* elf32-ppc.c (ppc_elf_add_symbol_hook): Likewise.
* elf32-sparc.c (elf32_sparc_add_symbol_hook): Likewise.
* elf64-ppc.c (ppc64_elf_add_symbol_hook): Likewise.
* elf64-sparc.c (elf64_sparc_add_symbol_hook): Likewise.
* lfxx-aarch64.c (_bfd_aarch64_elf_add_symbol_hook): Likewise.
* elf32-i386.c (elf_i386_check_relocs): Update has_gnu_symbols
if there are relocations against IFUNC symbols.
(elf_i386_add_symbol_hook): Don't check STT_GNU_IFUNC here.
* elf64-x86-64. (elf_x86_64_check_relocs): Update has_gnu_symbols
if there are relocations against IFUNC symbols.
(elf_x86_64_add_symbol_hook): Don't check STT_GNU_IFUNC here.
ld/testsuite/
PR ld/18815
* ld-i386/i386.exp: Run pr18815.
* ld-x86-64/x86-64.exp: Likewise.
* ld-i386/pr18815.d: New file.
* ld-i386/pr18815.s: Likewise.
* ld-x86-64/pr18815.d: Likewise.
* ld-x86-64/pr18815.s: Likewise.
BFD_RELOC_AARCH64_TLSLE_ADD_LO12 is used to generate simplest
one-instruction addressing for TLS LE model when tls size is smaller
4K. Linker need to make sure there is no TLS offset overflow.
2015-06-01 Jiong Wang <jiong.wang@arm.com>
bfd/
* elfnn-aarch64.c (elfNN_aarch64_howto_table): Set overflow type to
complain_overflow_unsigned for BFD_RELOC_AARCH64_TLSLE_ADD_LO12.
* elfxx-aarch64.c (_bfd_aarch64_elf_resolve_relocation): Don't use
PGOFF for BFD_RELOC_AARCH64_TLSLE_ADD_LO12, that will mask off all
potential high overflowed bits.
ld/testsuite/
* ld-aarch64/tprel_add_lo12_overflow.s: New testcase.
* ld-aarch64/tprel_add_lo12_overflow.d: Nex expectation file.
* ld-aarch64/aarch64-elf.exp: Run new testcase.
Some early revisions of the Cortex-A53 have an erratum (843419). The
details of the erratum are quite complex and involve dynamic
conditions. For the purposes of the workaround we have simplified the
static conditions to an ADRP in the last two instructions of a 4KByte
page, followed within four instructions by a load/store dependent on
the ADRP.
This patch adds support to conservatively scan for and workaround
Cortex A53 erratum 843419. There are two different workaround
strategies used. The first is to rewrite ADRP instructions which form
part of an erratum sequence with an ADR instruction. In situations
where the ADR provides insufficient offset the dependent load or store
instruction from the sequence is moved to a stub section and branches
are inserted from the original sequence to the relocated instruction
and back again.
Stub section sizes are rounded up to a multiple of 4096 in order to
ensure that the act of inserting work around stubs does not create
more errata sequences.
Workaround stubs are always inserted into the stub section associated
with the input section containing the erratum sequence. This ensures
that the fully relocated form of the veneered load store instruction
is available at the point in time when the stub section is written.
bfd/
PR gas/17843
* elfxx-aarch64.c (_bfd_aarch64_elf_put_addend): Expect
R_AARCH64_TLSLE_MOVW_TPREL_G0_NC and R_AARCH64_TLSLE_MOVW_TPREL_G1_NC
to be used with MOVK rather than MOVZ.
gas/
PR gas/17843
* config/tc-aarch64.c (process_movw_reloc_info): Allow
R_AARCH64_TLSLE_MOVW_TPREL_G0_NC and R_AARCH64_TLSLE_MOVW_TPREL_G1_NC
for MOVK.
gas/testsuite/
PR gas/17843
* gas/aarch64/tls.s, gas/aarch64/tls.d: Add test for
R_AARCH64_TLSLE_MOVW_TPREL_G0/R_AARCH64_TLSLE_MOVW_TPREL_G1_NC
sequence.
ld/testsuite/
PR gas/17843
* ld-aarch64/tlsle.s, ld-aarch64/tlsle.d: New test.
* ld-aarch64/aarch64-elf.exp: Run it.
