The linker merges all the input .sframe sections. When merging, the
linker verifies that all the input .sframe sections have the same
abi/arch.
The linker uses libsframe library to perform key actions on the
.sframe sections - decode, read, and create output data. This
implies buildsystem changes to make and install libsframe before
libbfd.
The linker places the output .sframe section in a new segment of its
own: PT_GNU_SFRAME. A new segment is not added, however, if the
generated .sframe section is empty.
When a section is discarded from the final link, the corresponding
entries in the .sframe section for those functions are also deleted.
The linker sorts the SFrame FDEs on start address by default and sets
the SFRAME_F_FDE_SORTED flag in the .sframe section.
This patch also adds support for generation of SFrame unwind
information for the .plt* sections on x86_64. SFrame unwind info is
generated for IBT enabled PLT, lazy/non-lazy PLT.
The existing linker option --no-ld-generated-unwind-info has been
adapted to include the control of whether .sframe unwind information
will be generated for the linker generated sections like PLT.
Changes to the linker script have been made as necessary.
ChangeLog:
* Makefile.def: Add install dependency on libsframe for libbfd.
* Makefile.in: Regenerated.
* bfd/Makefile.am: Add elf-sframe.c
* bfd/Makefile.in: Regenerated.
* bfd/bfd-in2.h (SEC_INFO_TYPE_SFRAME): Regenerated.
* bfd/configure: Regenerate.
* bfd/configure.ac: Add elf-sframe.lo.
* bfd/elf-bfd.h (struct sframe_func_bfdinfo): New struct.
(struct sframe_dec_info): Likewise.
(struct sframe_enc_info): Likewise.
(struct elf_link_hash_table): New member for encoded .sframe
object.
(struct output_elf_obj_tdata): New member.
(elf_sframe): New access macro.
(_bfd_elf_set_section_sframe): New declaration.
* bfd/elf.c (get_segment_type): Handle new segment
PT_GNU_SFRAME.
(bfd_section_from_phdr): Likewise.
(get_program_header_size): Likewise.
(_bfd_elf_map_sections_to_segments): Likewise.
* bfd/elf64-x86-64.c (elf_x86_64_link_setup_gnu_properties): Add
contents to the .sframe sections or .plt* entries.
* bfd/elflink.c (elf_section_ignore_discarded_relocs): Handle
SEC_INFO_TYPE_SFRAME.
(_bfd_elf_default_action_discarded): Handle .sframe section.
(elf_link_input_bfd): Merge .sframe section.
(bfd_elf_final_link): Write the output .sframe section.
(bfd_elf_discard_info): Handle discarding .sframe section.
* bfd/elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Create
.sframe section for .plt and .plt.sec.
(_bfd_x86_elf_finish_dynamic_sections): Handle .sframe from
.plt* sections.
* bfd/elfxx-x86.h (PLT_SFRAME_FDE_START_OFFSET): New
definition.
(SFRAME_PLT0_MAX_NUM_FRES): Likewise.
(SFRAME_PLTN_MAX_NUM_FRES): Likewise.
(struct elf_x86_sframe_plt): New structure.
(struct elf_x86_link_hash_table): New member.
(struct elf_x86_init_table): New members for .sframe
creation.
* bfd/section.c: Add new definition SEC_INFO_TYPE_SFRAME.
* binutils/readelf.c (get_segment_type): Handle new segment
PT_GNU_SFRAME.
* ld/ld.texi: Update documentation for
--no-ld-generated-unwind-info.
* ld/scripttempl/elf.sc: Support .sframe sections.
* ld/Makefile.am (TESTSFRAMELIB): Use it.
(check-DEJAGNU): Likewise.
* ld/Makefile.in: Regenerated.
* ld/configure.ac (TESTSFRAMELIB): Set to the .so or .a like TESTBFDLIB.
* ld/configure: Regenerated.
* bfd/elf-sframe.c: New file.
include/ChangeLog:
* elf/common.h (PT_GNU_SFRAME): New definition.
* elf/internal.h (struct elf_segment_map): Handle new segment
type PT_GNU_SFRAME.
ld/testsuite/ChangeLog:
* ld/testsuite/ld-bootstrap/bootstrap.exp: Add SFRAMELIB.
* ld/testsuite/ld-aarch64/aarch64-elf.exp: Add new test
sframe-simple-1.
* ld/testsuite/ld-aarch64/sframe-bar.s: New file.
* ld/testsuite/ld-aarch64/sframe-foo.s: Likewise.
* ld/testsuite/ld-aarch64/sframe-simple-1.d: Likewise.
* ld/testsuite/ld-sframe/sframe-empty.d: New test.
* ld/testsuite/ld-sframe/sframe-empty.s: New file.
* ld/testsuite/ld-sframe/sframe.exp: New testsuite.
* ld/testsuite/ld-x86-64/sframe-bar.s: New file.
* ld/testsuite/ld-x86-64/sframe-foo.s: Likewise.
* ld/testsuite/ld-x86-64/sframe-simple-1.d: Likewise.
* ld/testsuite/ld-x86-64/sframe-plt-1.d: Likewise.
* ld/testsuite/ld-x86-64/sframe-simple-1.d: Likewise.
* ld/testsuite/ld-x86-64/x86-64.exp: Add new tests -
sframe-simple-1, sframe-plt-1.
* ld/testsuite/lib/ld-lib.exp: Add new proc to check if
assembler supports SFrame section.
* ld/testsuite/ld-sframe/discard.d: New file.
* ld/testsuite/ld-sframe/discard.ld: Likewise.
* ld/testsuite/ld-sframe/discard.s: Likewise.
Data and instruction memories are strictly separated, so it is not
possible to execute instructions from the stack memory on PRU.
I don't see any difference in testsuite results with or without this
change.
bfd/ChangeLog:
* elf32-pru.c (elf_backend_default_execstack): Define as 0.
ld/ChangeLog:
* testsuite/ld-elf/elf.exp (target_defaults_to_execstack):
Return 0 for pru.
Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
This tidies SEC_RELOC handling in bfd, in the process fixing a bug
with objcopy when renaming sections.
bfd/
* reloc.c (_bfd_generic_set_reloc): Set/clear SEC_RELOC depending
on reloc count.
* elf64-sparc.c (elf64_sparc_set_reloc): Likewise.
binutils/
* objcopy.c (copy_relocations_in_section): Remove now unnecessary
clearing of SEC_RELOC.
* testsuite/binutils-all/rename-section-01.d: New test.
* testsuite/binutils-all/objcopy.exp: Run it.
gas/
* write.c (size_seg): Remove unneccesary twiddle of SEC_RELOC.
(write_relocs): Likewise. Always call bfd_set_reloc.
This patch provides a new function to sanity check section sizes.
It's mostly extracted from what we had in bfd_get_full_section_contents
but also handles compressed debug sections.
Improvements are:
- section file offset is taken into account,
- added checks that a compressed section can be read from file.
The function is then used when handling multiple .debug_* sections
that need to be read into a single buffer, to sanity check sizes
before allocating the buffer.
PR 26946, PR 28834
* Makefile.am (LIBBFD_H_FILES): Add section.c.
* compress.c (bfd_get_full_section_contents): Move section size
sanity checks..
* section.c (_bfd_section_size_insane): ..to here. New function.
* dwarf2.c (read_section): Use _bfd_section_size_insane.
(_bfd_dwarf2_slurp_debug_info): Likewise.
* Makefile.in: Regenerate.
* libbfd.h: Regenerate.
The idea here is the stop tools from allocating up to 32G per section
for the arelent pointer array, only to find a little later that the
section reloc count was fuzzed. This usually doesn't hurt much (on
systems that allow malloc overcommit) except when compiled with asan.
We already do this for ELF targets, and while fixing the logic
recently I decided other targets ought to do the same.
* elf64-sparc.c (elf64_sparc_get_reloc_upper_bound): Sanity check
section reloc count against file size.
* mach-o.c (bfd_mach_o_get_reloc_upper_bound): Likewise.
* aoutx.h (get_reloc_upper_bound): Likewise, and don't duplicate
check done in bfd_get_reloc_upper_bound.
* pdp11.c (get_reloc_upper_bound): Likewise.
* coffgen.c (coff_get_reloc_upper_bound): Likewise.
gas uses ZSTD_compressStream2 which is only available with libzstd >=
1.4.0, leading to build errors when an older version is installed.
This patch updates the check libzstd presence to check its version is
>= 1.4.0. However, since gas seems to be the only component requiring
such a recent version this may imply that we disable ZSTD support for
all components although some would still benefit from an older
version.
I ran 'autoreconf -f' in all directories containing a configure.ac
file, using vanilla autoconf-2.69 and automake-1.15.1. I noticed
several errors from autoheader in readline, as well as warnings in
intl, but they are unrelated to this patch.
This should fix some of the buildbots.
OK for trunk?
Thanks,
Christophe
Despite that the RISC-V ISA Manual version 2.2 prohibited "RV32EF", later
versions beginning with the version 20190608-Base-Ratified removed this
restriction. Because the 'E' extension is still a draft, the author chose
to *just* remove the conflict (not checking the ISA version).
Note that, because RV32E is only used with a soft-float calling convention,
there's no valid official ABI for RV32EF. It means, even if we can assemble
a program with -march=rv32ef -mabi=ilp32e, floating-point registers are kept
in an unmanaged state (outside ABI management).
The purpose of this commit is to suppress unnecessary errors while parsing
an ISA string and/or disassembling, not to allow hard-float with RVE.
bfd/ChangeLog:
* elfxx-riscv.c (riscv_parse_check_conflicts): Accept RV32EF
because only older specifications disallowed it.
gas/ChangeLog:
* testsuite/gas/riscv/march-fail-rv32ef.d: Remove as not directly
prohibited.
* testsuite/gas/riscv/march-fail-rv32ef.l: Likewise.
This patch is based on MULTIPLE_FRAME_SECTIONS and EH_FRAME_LINKONCE,
it allows backend to enable this feature and use '--gc-sections' simply.
* gas/dw2gencfi.h (TARGET_MULTIPLE_EH_FRAME_SECTIONS): New.
(MULTIPLE_FRAME_SECTIONS): Add TARGET_MULTIPLE_EH_FRAME_SECTIONS.
* gas/dw2gencfi.c (EH_FRAME_LINKONCE): Add TARGET_MULTIPLE_EH_FRAME_SECTIONS.
(is_now_linkonce_segment): Likewise.
(get_cfi_seg): Create relocation info between .eh_frame.* and .text.* section.
* bfd/elf-bfd.h (elf_backend_can_make_multiple_eh_frame): New.
* bfd/elfxx-target.h (elf_backend_can_make_multiple_eh_frame): Likewise.
* bfd/elflink.c (_bfd_elf_default_action_discarded): Add checking for
elf_backend_can_make_multiple_eh_frame.
And do the sanity check in a way that can't overflow.
* pef.c (bfd_pef_parse_function_stubs): Sanity check header
imported_library_count and total_imported_symbol_count before
allocating memory.
objcopy copy_object may omit the call to bfd_copy_private_bfd_data for
various conditions deemed non-fatal, in which case obj_som_exec_data
will be NULL for the output file.
* som.c (som_finish_writing): Don't dereference NULL
obj_som_exec_data.
RISC-V Psabi pr196,
https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/196
bfd/
* elfxx-riscv.c (riscv_release_subset_list): Free arch_str if needed.
(riscv_copy_subset_list): Copy arch_str as well.
* elfxx-riscv.h (riscv_subset_list_t): Store arch_str for each subset list.
gas/
* config/tc-riscv.c (riscv_reset_subsets_list_arch_str): Update the
architecture string in the subset_list.
(riscv_set_arch): Call riscv_reset_subsets_list_arch_str after parsing new
architecture string.
(s_riscv_option): Likewise.
(need_arch_map_symbol): New boolean, used to indicate if .option
directives do affect instructions.
(make_mapping_symbol): New boolean parameter reset_seg_arch_str. Need to
generate $x+arch for MAP_INSN, and then store it into tc_segment_info_data
if reset_seg_arch_str is true.
(riscv_mapping_state): Decide if we need to add $x+arch for MAP_INSN. For
now, only add $x+arch if the architecture strings in subset list and segment
are different. Besides, always add $x+arch at the start of section, and do
not add $x+arch for code alignment, since rvc for alignment can be judged
from addend of R_RISCV_ALIGN.
(riscv_remove_mapping_symbol): If current and previous mapping symbol have
same value, then remove the current $x only if the previous is $x+arch;
Otherwise, always remove previous.
(riscv_add_odd_padding_symbol): Updated.
(riscv_check_mapping_symbols): Don't need to add any $x+arch if
need_arch_map_symbol is false, so changed them to $x.
(riscv_frag_align_code): Updated since riscv_mapping_state is changed.
(riscv_init_frag): Likewise.
(s_riscv_insn): Likewise.
(riscv_elf_final_processing): Call riscv_release_subset_list to release
subset_list of riscv_rps_as, rather than only release arch_str in the
riscv_write_out_attrs.
(riscv_write_out_attrs): No need to call riscv_arch_str, just get arch_str
from subset_list of riscv_rps_as.
* config/tc-riscv.h (riscv_segment_info_type): Record current $x+arch mapping
symbol of each segment.
* testsuite/gas/riscv/mapping-0*: Merged and replaced by mapping.s.
* testsuite/gas/riscv/mapping.s: New testcase, to test most of the cases in
one file.
* testsuite/gas/riscv/mapping-symbols.d: Likewise.
* testsuite/gas/riscv/mapping-dis.d: Likewise.
* testsuite/gas/riscv/mapping-non-arch.s: New testcase for the case that
does need any $x+arch.
* testsuite/gas/riscv/mapping-non-arch.d: Likewise.
* testsuite/gas/riscv/option-arch-01a.d: Updated.
opcodes/
* riscv-dis.c (riscv_disassemble_insn): Set riscv_fpr_names back to
riscv_fpr_names_abi or riscv_fpr_names_numeric when zfinx is disabled
for some specfic code region.
(riscv_get_map_state): Recognized mapping symbols $x+arch, and then reset
the architecture string once the ISA is different.
elfnn-riscv.c: In function ‘riscv_relax_resolve_delete_relocs’:
elfnn-riscv.c:4256:30: error: operand of ‘?:’ changes signedness from ‘int’ to ‘unsigned int’ due to unsignedness of other operand [-Werror=sign-compare]
So make the operands unsigned could resolve problem.
bfd/
* elfnn-riscv.c (riscv_relax_resolve_delete_relocs): Fixed build
failures for -Werror=sign-compare.
The external reloc size check was wrong. Here asect is the code/data
section, not the reloc section. So using this_hdr gave the size of
the code/data section.
* elf.c (_bfd_elf_get_reloc_upper_bound): Properly get
external size from reloc headers.
This patch checks that relocations emitted in som_write_fixups have
offsets that are monotonic and within a section. To do that properly
using bfd_reloc_offset_in_range it is necessary to set the reloc howto
size field, which isn't used otherwise by the som backend. Note that
the sizes used are not exactly those in the old sizing switch
statement deleted from som_write_fixups, but all relocs handled by the
main switch statement there get the same size. Most unhandled relocs
get a zero size (exceptions being R_RELOCATION, R_SPACE_REF,
R_MILLI_REL, R_BREAKPOINT which all involve writing one word according
to my SOM reference). I figure it doesn't matter since any unhandled
reloc is converted to 0xff R_RESERVED, and a default of zero is better
for a "don't know" reloc.
Besides tidying the code, stringizing name from type in SOM_HOWTO
fixes R_REPEATED_INIT name.
* som.c (SOM_HOWTO): Add SIZE arg, delete NAME. Stringize type
to name.
(som_hppa_howto_table): Update with sizes.
(som_write_fixups): Delete sizing switch statement. Sanity check
bfd_reloc address against subsection size.
Fuzzed object files can put random values in bfd_reloc->address,
leading to large som_reloc_skip output.
* som.c (som_write_fixups): Allow for maximal som_reloc_skip.
On x86-64 the default ELF_MAXPAGESIZE depends on a configure
option (--disable-separate-code). Since 9833b775
("PR28824, relro security issues") we use max-page-size for relro
alignment (with a short interval, from 31b4d3a ("PR28824, relro
security issues, x86 keep COMMONPAGESIZE relro") to its revert
a1faa5ea, where x86-64 only used COMMONPAGESIZE as relro alignment
target).
But that means that a linker configured with --disable-separate-code
behaves different from one configured with --enable-separate-code
(the default), _even if using "-z {no,}separate-code" option to use
the non-configured behaviour_ . In particular it means that when
configuring with --disable-separate-code the linker will produce
binaries aligned to 2MB pages on disk, and hence generate 2MB
executables for a hello world (and even 6MB when linked with
"-z separate-code").
Generally we can't have constants that ultimately land in static
variables be depending on configure options if those only influence
behaviour that is overridable by command line options.
So, do away with that, make the default MAXPAGESIZE be 4k (as is default
for most x86-64 configs anyway, as most people won't configure with
--disable-separate-code). If people need more they can use the
"-z max-page-size" (with would have been required right now for a
default configure binutils).
bfd/
* elf64-x86-64.c (ELF_MAXPAGESIZE): Don't depend on
DEFAULT_LD_Z_SEPARATE_CODE.
The R_RISCV_DELETE relocations are no longer deleted at another relax pass,
so we should reset 'again' flag to true for _bfd_riscv_relax_pc, while the
deleted bytes are marked as R_RISCV_DELETE.
bfd/
* elfnn-riscv.c (_bfd_riscv_relax_pc): Set `again' to true while the
deleted bytes are marked as R_RISCV_DELETE.
The riscv port does deletion and symbol table update for each relocation
while relaxing, so we are moving section bytes and scanning symbol table once
for each relocation. Compared to microblaze port, they record the relaxation
changes into a table, then do the deletion and symbol table update once per
section, rather than per relocation. Therefore, they should have better link
time complexity than us.
To improve the link time complexity, this patch try to make the deletion in
linear time. Compared to record the relaxation changes into a table, we
replace the unused relocation with R_RISCV_DELETE for the deleted bytes, and
then resolve them at the end of the section. Assuming the number of
R_RISCV_DELETE is m, and the number of symbols is n, the total link complexity
should be O(m) for moving section bytes, and O(m*n^2) for symbol table update.
If we record the relaxation changes into the table, and then sort the symbol
table by values, then probably can reduce the time complexity to O(m*n*log(n))
for updating symbol table, but it doesn't seem worth it for now.
bfd/
* elfnn-riscv.c (_riscv_relax_delete_bytes): Renamed from
riscv_relax_delete_bytes, updated to reduce the tiem complexity to O(m)
for memmove.
(typedef relax_delete_t): Function pointer declaration of delete functions.
(riscv_relax_delete_bytes): Can choose to use _riscv_relax_delete_piecewise
or _riscv_relax_delete_immediate for deletion.
(_riscv_relax_delete_piecewise): Just mark the deleted bytes as R_RISCV_DELETE.
(_riscv_relax_delete_immediate): Delete some bytes from a section while
relaxing.
(riscv_relax_resolve_delete_relocs): Delete the bytes for R_RISCV_DELETE
relocations from a section, at the end of _bfd_riscv_relax_section.
(_bfd_riscv_relax_call): Mark deleted bytes as R_RISCV_DELETE by reusing
R_RISCV_RELAX.
(_bfd_riscv_relax_lui): Likewise, but reuse R_RISCV_HI20 for lui, and reuse
R_RISCV_RELAX for c.lui.
(_bfd_riscv_relax_tls_le): Likewise, but resue R_RISCV_TPREL_HI20 and
R_RISCV_TPREL_ADD.
(_bfd_riscv_relax_pc): Likewise, but resue R_RISCV_PCREL_HI20 for auipc.
(_bfd_riscv_relax_align): Updated, don't need to resue relocation since
calling _riscv_relax_delete_immediate.
(_bfd_riscv_relax_delete): Removed.
(_bfd_riscv_relax_section): Set riscv_relax_delete_bytes for each relax_func,
to delete bytes immediately or later. Call riscv_relax_resolve_delete_relocs
to delete bytes for DELETE relocations from a section.
