So far, SFrame sections were of type SHT_PROGBITS.
As per ELF specification, SHT_PROGBITS indicates that the section holds
information defined by the program, whose format and meaning are
determined solely by the program.
On the linker side, SHT_PROGBITS should be reserved for the simple "cat
contents after applying relocs" semantics.
Currently, the only way to know that a section contains SFrame stack
trace data is if consumer checks for section name. Such a check for
section name is not quite conformant to ELF principles.
Some of this was discussed here
https://sourceware.org/pipermail/binutils/2025-March/140181.html
With this change, the SFrame sections generated by gas, ld will have
section type set to SHT_GNU_SFRAME. The new section type is defined in
the SHT_LOOS/SHT_HIOS space. The SFrame parsing routine
_bfd_elf_parse_sframe () now admits sections only when the the section
type is SHT_GNU_SFRAME.
No special handling / validation is done at the moment for the case of
manual creation of SFrame sections via obj_elf_section (). Add function
level comments for now to add a note about this.
Although the default handling for (sh_type >= SHT_LOOS && sh_type <=
SHT_HIOS) is sufficient when SHT_GNU_SFRAME is in that range, it makes
sense to add it as a case of its own.
bfd/
* elf-sframe.c (_bfd_elf_parse_sframe): Check if section type is
SHT_GNU_SFRAME.
(_bfd_elf_set_section_sframe): Set SHT_GNU_SFRAME for output
SFrame section.
* elflink.c (obj_elf_section): Use section type for check
instead of section name.
* elfxx-x86.c: Set SHT_GNU_SFRAME for SFrame sections for
.plt* sections.
* elf.c (bfd_section_from_shdr): Add case for SHT_GNU_SFRAME.
binutils/
* readelf.c (get_os_specific_section_type_name): Add
SHT_GNU_SFRAME.
gas/
* NEWS: Announce emitted SFrame sections have SHT_GNU_SFRAME
set.
* config/obj-elf.c (obj_elf_attach_to_group): Add comments to
indicate no special handling for SFrame yet.
* dw2gencfi.c (cfi_finish): Set SHT_GNU_SFRAME for emitted
SFrame section.
ld/
* NEWS: Announce emitted SFrame sections have SHT_GNU_SFRAME
set.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Add new test.
* gas/cfi-sframe/cfi-sframe-common-1b.d: New test.
* gas/cfi-sframe/cfi-sframe-common-1b.s: New test.
include/
* elf/common.h (SHT_GNU_SFRAME): Add new section type for SFrame
stack trace information.
libsframe/doc/
* sframe-spec.texi: Add expected ELF section type.
Enable SFrame stack tracing through PLT entries. Based on x86-64.
On s390x both PLT0 and PLTn entries are 32-bytes in size. Their code
neither alters the stack pointer (SP), frame pointer (FP), nor return
address (RA) registers. Therefore the PLT0 can be represented using
a SFrame FDE of type PCINC with a single SFrame FRE and the PLTn can
be represented using a SFrame FDE of type PCMASK, with a repetition
block size of 32 (PLTn size), and a single SFrame FRE.
Note that as both the PLT0 entry and the PLTn entries have equal size
and could both be represented using the identical SFrame FRE, the whole
.plt section on s390x could be represented using a single SFrame FDE of
type PCMASK, with a repetition block size of 32 (PLT0 and PLTn size),
and a single SFrame FRE. Keep the x86-64 logic with separate SFrame
FDEs for PLT0 and PLTn, to ease potential generalization of the .sframe
for .plt generation logic among architectures.
bfd/
* elf64-s390.c: Include sframe.h and sframe-api.h.
(PLT_SFRAME_FDE_START_OFFSET, SFRAME_PLT0_MAX_NUM_FRES,
SFRAME_PLTN_MAX_NUM_FRES, elf_s390x_sframe_plt_fre,
elf_s390x_sframe_plt): New .sframe template for .plt section.
(elf_s390_link_hash_table): Add plt_cfe_ctx, plt_sframe, and
sframe_plt fields.
(_bfd_s390_elf_create_sframe_plt): New function. Fill in
.sframe section for .plt section.
(_bfd_s390_elf_write_sframe_plt): New function. Write .sframe
section.
(elf_s390_create_dynamic_sections): Create .sframe section for
.plt section.
(elf_s390_late_size_sections): Call
_bfd_s390_elf_create_sframe_plt and
_bfd_s390_elf_write_sframe_plt.
(elf_s390_finish_dynamic_sections): Write .plt section start
into .sframe FDE covering .plt section. Call
_bfd_elf_merge_section_sframe on htab->plt_sframe.
ld/
* NEWS: Add news entry.
ld/testsuite/
* ld-s390/s390.exp: Add new test.
* ld-s390/sframe-plt-1.d: New linker-generated .sframe for .plt
test.
* ld-s390/sframe-simple-1.d: Adjust expected test output due to
linker-generated .sframe for .plt.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
The SFrame FDE's function start address is always emitted as follows by
GAS and ld: it is the offset of the start PC of the respective function
from the FDE field itself.
GAS and ld will emit a flag SFRAME_F_FDE_FUNC_START_PCREL set to 1
when emitting the field in this encoding.
* binutils/NEWS: Announce the change of encoding for SFrame FDE
func start addr field.
* gas/NEWS: Announce the emission of new flag
SFRAME_F_FDE_FUNC_START_PCREL.
* ld/NEWS: Likewise. Relocatable links are now fixed.
This patch locates the linker stubs / trampolines *after* all the .progmem
sections. This is the natural placement since progmem data has to reside
in the lower 64 KiB (it is accessed using LPM), whereas the linker stubs
are only required to be located in the lower 128 KiB of program memory.
(They must be in the range of EICALL / EIJMP with EIND = 0.)
The current location of the linker stubs was motivated by an invalid test
case from PR13812 that allocates more than 64 KiB of progmem data.
The patch adds an assertion that makes sure that no progmem data is
allocated past 0xffff.
Data that is accessed using ELPM should be located to .progmemx so that
no .progmem addresses are wasted. .progmemx was introduced in 2017 and
is used by __memx, __flashx and by the current AVR-LibC.
(The compiler uses .jumptables.gcc for its jump dispatch tables since
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63223 / GCC v4.9.2).
PR ld/32968
ld/
* scripttempl/avr.sc: Move the trampolines section after the
.progmem sections. Assert that .progmem is in the lower 64 KiB.
The -taso switch was quite useful 25 years ago for porting 32-bit
code with broken integer-pointer casting. Not anymore. The EF_ALPHA_32BIT
Linux support is going to be dropped in kernel v6.14 [1], NetBSD and OpenBSD
never had it, so there is no point in keeping the -taso option around.
Also remove alpha special case that uses -taso from gdb.base/dump.exp
in gdb testsuite.
[1] https://lore.kernel.org/all/87jzb2tdb7.fsf_-_@email.froward.int.ebiederm.org
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Reviewed-By: Maciej W. Rozycki <macro@orcam.me.uk>
Approved-By: Andrew Burgess <aburgess@redhat.com>
Enable unwinding using .eh_frame information through PLT entries. Based
on x86-64.
This enhances stack traces if the instruction pointer is in a PLT entry.
For instance perf call graphs, when using --call-graph=dwarf, and Glibc
backtraces, when using backtrace() e.g. from a signal handler.
Note that GDB could already unwind through PLT entries using its s390-
specific prologue unwinder.
Furthermore this lays the foundation to generate SFrame information for
the PLT section in the future.
bfd/
* elf64-s390.c: Include dwarf2.h.
(PLT_CIE_SIZE, PLT_FDE_SIZE,
PLT_FDE_START_OFFSET, PLT_FDE_LEN_OFFSET,
elf_s390x_eh_frame_plt): New .eh_frame template for .plt
section.
(elf_s390_link_hash_table): Add plt_eh_frame field.
(elf_s390_create_dynamic_sections): New s390-specific wrapper
around _bfd_elf_create_dynamic_sections. Create .eh_frame
section for .plt section.
(elf_backend_create_dynamic_sections): Register s390-specific
elf_s390_create_dynamic_sections.
(elf_s390_late_size_sections): Fill in .eh_frame section for
.plt section. Write .plt section size into .eh_frame FDE
covering .plt section.
(elf_s390_finish_dynamic_sections): Write .plt section start
into .eh_frame FDE covering .plt section. Call
_bfd_elf_write_section_eh_frame on on htab->plt_eh_frame
section.
ld/
* NEWS: Add news entry.
* emulparams/elf64_s390.sh: Include plt_unwind.sh.
ld/testsuite/
* ld-s390/plt_64-1_eh.wf: New PLT .eh_frame generation test.
* ld-s390/s390.exp: Link some existing test cases with
--no-ld-generated-unwind-info so that they do not fail. Run
new PLT .eh_frame generation test.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
The GNU_PROPERTY_MEMORY_SEAL gnu property is a way to mark binaries
to be memory sealed by the loader, to avoid further changes of
PT_LOAD segments (such as unmapping or change permission flags).
This is done along with Linux kernel (the mseal syscall [1]), and
C runtime supports to instruct the kernel on the correct time during
program startup (for instance, after RELRO handling). This support
is added along the glibc support to handle the new gnu property [2].
This is a opt-in security features, like other security hardening
ones like NX-stack or RELRO.
The new property is ignored if present on ET_REL objects, and only
added on ET_EXEC/ET_DYN if the linker option is used. A gnu property
is used instead of DT_FLAGS_1 flag to allow memory sealing to work
with ET_EXEC without PT_DYNAMIC support (at least on glibc some ports
still do no support static-pie).
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=8be7258aad44b5e25977a98db136f677fa6f4370
[2] https://sourceware.org/pipermail/libc-alpha/2024-September/160291.html
Change-Id: Id47fadabecd24be0e83cff45653f7ce9a900ecf4
The Nios II architecture has been EOL'ed by the vendor. This patch
removes all binutils, bfd, gas, binutils, and opcodes support for this
target with the exception of the readelf utility. (The ELF EM_*
number remains valid and the relocation definitions from the Nios II
ABI will never change in future, so retaining the readelf support
seems consistent with its purpose as a utility that tries to parse the
headers in any ELF file provided as an argument regardless of target.)
Specifying the compiler flag `-Wl,--package-metadata=<JSON>` will not
work in case the JSON contains a comma, because compiler drivers eat
commas. Example:
```
$ echo "void main() { }" > test.c
$ gcc '-Wl,--package-metadata={"type":"deb","os":"ubuntu"}' test.c
/usr/bin/ld: cannot find "os":"ubuntu"}: No such file or directory
collect2: error: ld returned 1 exit status
```
The quotation marks in the JSON value do not work well with shell nor
make. Specifying the `--package-metadata` linker flag in a `LDFLAGS`
environment variable might loose its quotation marks when it hits the
final compiler call.
So support percent-encoded and %[string] encoded JSON data in the
`--package-metadata` linker flag. Percent-encoding is used because it is
a standard, simple to implement, and does take too many additional
characters. %[string] encoding is supported for having a more readable
encoding.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32003
Bug-Ubutru: https://bugs.launchpad.net/bugs/2071468
Signed-off-by: Benjamin Drung <benjamin.drung@canonical.com>
LLD has dropped the option -Ttext-segment for specifying image base
addresses, instead forcing the use of the --image-base option for both
ELF and PE targets. As it stands, GNU LD and LLVM LLD are incompatible,
having two different options for the same functionality.
This patch enables the use of --image-base on ELF targets, advancing
consistency and compatibility.
See: https://reviews.llvm.org/D70468https://maskray.me/blog/2020-11-15-explain-gnu-linker-options#address-relatedhttps://sourceware.org/bugzilla/show_bug.cgi?id=25207
Moreover, a new test has been added to ensure -z separate-code behaviour
when used with -Ttext-segment stays the same. When this combination is
used, -Ttext-segment sets the address of the first segment (R), not the
text segment (RX), and like with -z noseparate-code, no segments lesser
than the specified address are created. If this behaviour was to change,
the first (R) segment of the ELF file would begin in a lesser address
than the specified text (RX) segment, breaking traditional use of this
option for specifying image base address.
The is patch adds a new ld build-id computation mode, "xx", using
xxhash in its 128-bit mode. The patch prereqs the xxhash-devel
headers being installed, and uses the "all-inlined" model, so no
run-time or link-time library dependence exists.
The xxhash mode performs well, saving roughly 20% of total userspace
run time from an ld job over a 800MB shared library relative to sha1.
128 bits of good hash should be collision-resistant to a number of
distinct binaries that numbers in the 2**32 - 2**64 range, even if not
"crypto" level hash. Confirmations of this are in progress.
ld/configury: add --with-xxhash mode, different from gdb case
because only using it in inline mode
ld/ldbuildid.c: add "xx" mode, #if WITH_XXHASH
ld/NEWS, ld.texi: mention new option
ld/lexsup.c: add enumeration of --build-id STYLES to --help
ld/testsuite/ld-elf/build-id.exp: add test case for 0xHEX case
and conditional for xx case;
also, simply tcl list syntax
https://inbox.sourceware.org/binutils/20240917201509.GB26396@redhat.com/
Signed-off-by: Frank Ch. Eigler <fche@redhat.com>
Change 2.42 to 2.43 for binutils 2.43 NEWS entries.
binutils/
* NEWS: Change 2.42 to 2.43 for 2.43 NEWS entries.
ld/
* NEWS: Change 2.42 to 2.43 for 2.43 NEWS entries.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Add -plugin-save-temps to store plugin intermediate files permanently.
It can be used to exam the final input object files generated from IR
inputs.
* NEWS: Mention -plugin-save-temps.
* ld.h (ld_config_type): Add plugin_save_temps.
* ld.texi: Document -plugin-save-temps.
* ldlex.h (option_values): Add OPTION_PLUGIN_SAVE_TEMPS.
* lexsup.c (ld_options): Add -plugin-save-temps.
(parse_args): Handle OPTION_PLUGIN_SAVE_TEMPS.
* plugin.c (plugin_call_cleanup): Don't call plugin
cleanup_handler for -plugin-save-temps.
Add --enable-mark-plt linker configure option to mark PLT entries with
DT_X86_64_PLT, DT_X86_64_PLTSZ and DT_X86_64_PLTENT dynamic tags by
default.
* NEWS: Mention -z mark-plt/-z nomark-plt and --enable-mark-plt.
* config.in: Regenerated.
* configure: Likewise.
* configure.ac: Add --enable-mark-plt.
(DEFAULT_LD_Z_MARK_PLT): New AC_DEFINE_UNQUOTED.
* emulparams/x86-64-plt.sh (PARSE_AND_LIST_OPTIONS_X86_64_PLT):
Support DEFAULT_LD_Z_MARK_PLT.
* emultempl/elf-x86.em (elf_x86_64_before_parse): New function.
(LDEMUL_BEFORE_PARSE): New. Set to elf_x86_64_before_parse for
x86-64 targets.
Adds two new external authors to etc/update-copyright.py to cover
bfd/ax_tls.m4, and adds gprofng to dirs handled automatically, then
updates copyright messages as follows:
1) Update cgen/utils.scm emitted copyrights.
2) Run "etc/update-copyright.py --this-year" with an extra external
author I haven't committed, 'Kalray SA.', to cover gas testsuite
files (which should have their copyright message removed).
3) Build with --enable-maintainer-mode --enable-cgen-maint=yes.
4) Check out */po/*.pot which we don't update frequently.
* Problematic fix commit,
2029e13917
RISC-V: Clarify the behaviors of SET/ADD/SUB relocations
* Bugzilla,
https://sourceware.org/bugzilla/show_bug.cgi?id=31179#c5
The addend of SUB_ULEB128 should be zero if using .uleb128, but we make it
non-zero by accident in assembler before. This causes troubles by applying
the above commit, since the calculation is changed to support .reloc *SUB*
relocations with non-zero addend.
We encourage people to rebuild their stuff to get the non-zero addend of
SUB_ULEB128, but that might need some times, so report warnings to inform
people need to rebuild their stuff if --check-uleb128 is enabled.
Since the failed .reloc cases for ADD/SET/SUB/ULEB128 are rarely to use,
it may acceptable that stop supproting them until people rebuld their stuff,
maybe half-year or a year later. Or maybe we should teach people that don't
write the .reloc R_RISCV_SUB* with non-zero constant, and then report
warnings/errors in assembler.
bfd/
* elfnn-riscv.c (perform_relocation): Ignore the non-zero addend of
R_RISCV_SUB_ULEB128.
(riscv_elf_relocate_section): Report warnings to inform people need
to rebuild their stuff if --check-uleb128 is enabled. So that can
get the right non-zero addend of R_RISCV_SUB_ULEB128.
* elfxx-riscv.h (struct riscv_elf_params): Added bool check_uleb128.
ld/
* NEWS: Updated.
* emultempl/riscvelf.em: Added linker risc-v target options,
--[no-]check-uleb128, to enable/disable checking if the addend of
uleb128 is non-zero or not. So that people will know they need to
rebuild the objects with binutils 2.42 and up, to get the right zero
addend of SUB_ULEB128 relocation, or they may get troubles if using
.reloc.
* ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp: Updated.
* ld/testsuite/ld-riscv-elf/pr31179*: New test cases.
PR 27565
* ldlex.l: Add REVERSE.
* ldgram.y: Allow REVERSE to be used wherever a sorting command can be used.
* ld.h (struct wildcard_spec): Add 'reversed' field.
* ldlang.h (lang_wild_statement_struct): Add 'filenames_reversed' field.
* ldlang.c (compare_sections): Add reversed parameter. (wild_sort): Reverse the comparison if requested. (print_wild_statement): Handle the reversed field.
* ld.texi: Document the new feature.
* NEWS: Mention the new feature.
* testsuite/ld-scripts/sort-file-reversed-1.d: New test driver.
* testsuite/ld-scripts/sort-file-reversed-1.t: New test source.
* testsuite/ld-scripts/sort-file-reversed-2.t: New test source.
* testsuite/ld-scripts/sort-file-reversed-2.d: New test driver.
* testsuite/ld-scripts/sort-sections-reversed-1.d: New test driver.
* testsuite/ld-scripts/sort-sections-reversed-1.t: New test source.
* testsuite/ld-scripts/sort-sections-reversed-2.t: New test source.
* testsuite/ld-scripts/sort-sections-reversed-2.d: New test driver.
* testsuite/ld-scripts/sort-sections-reversed-3.d: New test driver.
* testsuite/ld-scripts/sort-sections-reversed-3.t: New test source.
PR 30374
* ldfile.c (struct input_remap): New structure. (ldfile_add_remap): New function. (ldfile_remap_input_free): New function. (ldfile_add_remap_file): New function. (ldfile_possibly_remap_input): New function. (ldfile_print_input_remaps): New function. * ldfile.h: Add prototypes for new functions.
* ldlang.c (new_afile): Call ldfile_possibly_remap_input. (lang_finish): Call ldfile_remap_input_free. (lang_map): Call ldfile_print_input_remaps.
* ldlex.h (OPTION_REMAP_INPUTS, OPTION_REMAP_INPUTS_FILE): Define.
* lexsup.c (ld_options): Add --remap-inputs-file and --remap-inputs. (parse_args): Handle new options.
* NEWS: Mention the new feature.
* ld.texi: Document the new options.
* testsuite/ld-misc/input-remap.exp: New test driver.
* testsuite/ld-misc/remaps.r: New file: Expected linker output.
* testsuite/ld-misc/remaps.txt: New file. Input remaps file.
PR 16566
* ldlang.c (ld_is_local_symbol): New function. (print_input_section): Add code to display local symbols in the section.
* ldlex.h (enum option_values): Add OPTION_PRINT_MAP_LOCALS and OPTION_PRINT_MAP_LOCALS.
* lexsup.c (ld_options[]): Add entries for --print-map-locals and --no-print-map-locals.
* NEWS: Mention the new feature.
* ld.h (struct ld_config_type): Add print_map_locals field.
* ld.texi: Document the new command line option.
* testsuite/ld-scripts/sizeof.s: Add a local symbol.
* testsuite/ld-scripts/map-locals.d: New test control file.
* testsuite/ld-scripts/map-address.exp: Run the new test.
Revert "Prevent the ASCII linker script directive from generating huge amounts of padding if the size expression is not a constant."
This reverts commit adbe951fc9.
Revert "ld test asciz and ascii fails"
This reverts the ascii.d part of commit 5f497256be.
Revert "Add support for the ASCII directive inside linker scripts."
This mostly reverts commit 9fe129a410
leaving the asciz.d and asciz.t changes in place.
This is a hopefully temporary reversion of new ld features for
embedded processors by Ulf Samuelsson, plus some followup patches.
Squashed together from the following:
Revert "lddigest 32-bit support and gcc-4 compile errors"
This reverts commit d7ee19be87110a8f5342cec6e323d83d01c641d1.
Revert "ld: Use correct types for crc64 calculations"
This reverts commit 9a534b9f8e.
Revert "Re: DIGEST: testsuite"
This reverts commit c8e85484d8.
Revert "Regen potfiles"
This reverts commit 4d98c966f8.
Revert "DIGEST: Makefile.*"
This reverts commit 78ef6ab03f.
Revert "DIGEST: calculation"
This reverts commit 5243990191.
Revert "DIGEST: ldlang.*: add timestamp"
This reverts commit bd9466d4aa.
Revert "DIGEST: ldmain.c"
This reverts commit c8f8653fa7.
Revert "DIGEST: ldgram.y"
This reverts commit d73c01be26.
Revert "DIGEST: ldlex.l"
This reverts commit 48b5163a9d.
Revert "DIGEST: testsuite"
This reverts commit a4135d1a48.
Revert "DIGEST: Documentation"
This reverts commit 3ec28966c3.
Revert "DIGEST: NEWS"
This reverts commit 099bf2927d.
Revert "DIGEST: LICENSING"
This reverts commit 5c8a0c6654.
