| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
For relocatable links the output .sframe section size may be wrong.
This can be observed when dumping the SFrame information from the x86-64
sframe-reloc-1 test:
Name Address Off Size
.sframe 0000000000000000 000110 00007f
Offset Type Symbol's Value Symbol's Name + Addend
000000000000001c R_X86_64_PC32 0000000000000000 .text + 1c
0000000000000030 R_X86_64_PC32 0000000000000000 .text + 65
0x00000000 e2de0201 0300f800 02000000 08000000 ................
0x00000010 1e000000 00000000 28000000 00000000 ........(.......
0x00000020 35000000 00000000 04000000 00000000 5...............
0x00000030 00000000 25000000 0f000000 04000000 ....%...........
offset 1st FRE---^^^^^^^^ ^^^^^^^^---number of FREs
0x00000040 00000000 00030801 0510f004 0410f034 ...............4
FDE info---^^ | begin of FDEs
0x00000050 0508f000 03080105 10f00404 10f02405 ..............$.
11111112222222223333333334444---FRE 1, 2, 3, 4
0x00000060 08f00000 00000000 00000000 00000000 ................
4444^^^^...
0x00000070 00000000 00000000 00000000 000000 ...............
...^^^^^^---excessive section
When running the x86-64 test cross build on a big-endian system, such
as s390x, objdump and readelf fail to dump the SFrame information with
the following error message:
Error: SFrame decode failure: Buffer does not contain SFrame data.
This is because the following check in flip_sframe() fails, which gets
only invoked if the endianness of the SFrame data is different from the
host system one:
/* All FDEs and FREs must have been endian flipped by now. */
if ((j != ihp->sfh_num_fres) || (bytes_flipped != (buf_size - hdrsz)))
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
With:
j=8, ihp->sfh_num_fres=8, bytes_flipped=70, buf_size=127, hdrsz=28
While at it, remove the incorrect code comment. There is no
relationship between "do not update size" and the fact that the
"contents have not been relocated".
bfd/
* elf-sframe.c (_bfd_elf_write_section_sframe): Update section
size also for relocatable links.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
---
[Changes in V4]
- Adjust commit log to indicate that the comment being removed was
bogus to begin with.
[End of changes in V4]
[No changes in V3]
[No changes in V2]
|
|
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_ADDR_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_ADDR_PCREL.
* ld/NEWS: Likewise. Relocatable links are now fixed.
---
[Changes in V4]
- In gas/NEWS, updated:
From: "Setting the flag is necessary for fixing relocatable SFrame links"
To: "Setting the flag ensures compliance with the updated SFrame V2 specification"
[End of changes in V4]
[Changes in V3]
- Add items in gas/NEWS and ld/NEWS too.
- Adjusted binutils/NEWS text a bit.
[End of changes in V3]
[No changes in V2]
|
|
PR/32666 Incorrect .rela.sframe when using ld -r
Input SFrame sections are merged using _bfd_elf_merge_section_sframe (),
which clubs all SFrame FDEs together in one blob and all SFrame FREs in
another. This, of course, means the offset of an SFrame FDE in the output
section cannot be simply derived from the output_offset of the sections.
Fix this by providing _bfd_elf_sframe_section_offset () which returns
the new offset of the SFrame FDE in the merged SFrame section.
Unlike EH_Frame sections, which also use the _bfd_elf_section_offset (),
to update the r_offset, SFrame sections have distinct merging semantics.
In case of SFrame, the SFrame FDE will not simply sit at location
"sec->output_offset + offset of SFrame FDE in sec". Recall that information
layout in an SFrame section is as follows:
SFrame Header
SFrame FDE 1
SFrame FDE 2
...
SFrame FDEn
SFrame FREs (Frame Row Entries)
Note how the SFrame FDEs and SFrame FREs are clubber together in groups
of their own.
Next, also note how the elf_link_input_bfd () does a:
irela->r_offset += o->output_offset;
This, however, needs to be avoided for SFrame sections because the
placement of all FDEs is at the beginning of the section. So, rather than
conditionalizing this as follows:
if (o->sec_info_type != SEC_INFO_TYPE_SFRAME)
irela->r_offset += o->output_offset;
the implementation in _bfd_elf_sframe_section_offset () does a reverse
adjustment, so that the generic parts of the linking process in
elf_link_input_bfd () are not made to do SFrame specific adjustments.
Add a new enum to track the current state of the SFrame input section
during the linking process (SFRAME_SEC_DECODED, SFRAME_SEC_MERGED) for
each input SFrame section. This is then used to assert an assumption
that _bfd_elf_sframe_section_offset () is being used on an input SFrame
sections which have not been merged (via
_bfd_elf_merge_section_sframe ()) yet.
bfd/
* elf-bfd.h: New declaration.
* elf-sframe.c (_bfd_elf_sframe_section_offset): New definition.
* elf.c (_bfd_elf_section_offset): Adjust offset if SFrame
section.
ld/testsuite/
* ld-x86-64/x86-64.exp: New test.
* ld-x86-64/sframe-reloc-1.d: New test.
---
Notes:
This patch was previously reviewed.
https://inbox.sourceware.org/binutils/d914ea1f-6c11-4ef5-ac15-404fd7afd26d@suse.com/
There was a comment on moving this
if (o->sec_info_type != SEC_INFO_TYPE_SFRAME)
irela->r_offset += o->output_offset;
to inside the _bfd_elf_sframe_section_offset () or keep it in
elf_link_input_bfd () with some code comments. Although, I think
keeping it deliberatly out of _bfd_elf_sframe_section_offset () was
clearer as that helped keep the contract of _bfd_elf_section_offset ()
symmetrical across section types. That said, taking the overall
opinions shared in the previous review, I have moved the stub inside
_bfd_elf_sframe_section_offset (). But if opinions have changed, I am
happy to bring the conditional back to elf_link_input_bfd ().
[No changes in V4]
[No changes in V3]
[No changes in V2]
|
|
This patch convenes a set of changes in bfd, gas, ld, libsframe towards
moving to the new encoding for the 'sfde_func_start_address' field in
SFrame FDE.
First, gas must now mark all SFrame sections with the new flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL. gas was already emitting the field
in the said encoding.
* gas/gen-sframe.c (output_sframe_internal): Emit the flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL.
Similarly for ld, adopt the new semantics of sfde_func_start_address
consistently. This means:
- When merging SFrame sections, check that all input SFrame sections
have the SFRAME_F_FDE_FUNC_START_ADDR_PCREL flag set. If the check
fails, ld errors out.
- When merging SFrame sections, keep even the in-memory contents of
the FDE function start address (buffer passed to libsframe
sframe_encoder_write () for writing out) are encoded in the new
semantics. While it is, in theory, possible that instead of doing this
change here, we adjust the value of sfde_func_start_address at the final
write (sframe_encoder_write) time. But latter is not favorable for
maintenanance and may be generally confusing for developers.
- When creating SFrame for PLT entries, emit flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL.
include/
* sframe-api.h (SFRAME_F_LD_MUSTHAVE_FLAGS): New definition.
bfd/
* elf-sframe.c (_bfd_elf_merge_section_sframe): Check for flag
combinatation SFRAME_F_LD_MUSTHAVE_FLAGS set for all input and
output SFrame sections. If not, error out. Also, adopt the new
semantics of function start address encoding.
* bfd/elfxx-x86.c (_bfd_x86_elf_create_sframe_plt): Emit flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL.
Next, for dumping SFrame sections, now that we are emitting the same
encoding in GAS, non-relocatable and relocatable SFrame links, it is the
time to set relocate to TRUE in debug_displays[].
binutils/
* dwarf.c (struct dwarf_section_display): Allow sframe sections
to now be relocated.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe-aarch64-pac-ab-key-1.d: Update the
test. Relocatable SFrame sections now display non-zero value
(appropriate function start address).
Now, as the SFrame sections on-disk and in-memory use the new semantics of
sfde_func_start_address encoding (i.e., function start address is the
offset from the sfde_func_start_address field to the start PC), the
calculation to make it human readable (i.e., relatable to the addresses
in .text sections) needs adjustment.
libsframe/
* sframe-dump.c (dump_sframe_func_with_fres): Adjust the
function start address for dumping.
Now that both the emission of the new encoding, and the relocation of
sections before dumping them is in place, it is time to adjust the
testcases.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe-aarch64-1.d: Update expected output
to include SFRAME_F_FDE_FUNC_START_ADDR_PCREL instead of NONE.
* gas/cfi-sframe/cfi-sframe-aarch64-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-aarch64-3.d: Likewise.
* gas/cfi-sframe/cfi-sframe-aarch64-4.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-10.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-11.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-3.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-4.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-5.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-6.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-7.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-8.d: Likewise.
* gas/cfi-sframe/cfi-sframe-common-9.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-empty-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-empty-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-empty-3.d: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-empty-4.d: Likewise.
* gas/cfi-sframe/common-empty-1.d: Likewise.
* gas/cfi-sframe/common-empty-2.d: Likewise.
* gas/cfi-sframe/common-empty-3.d: Likewise.
* gas/scfi/x86_64/scfi-cfi-sections-1.d: Likewise.
* gas/scfi/x86_64/scfi-dyn-stack-1.d: Likewise.
ld/testsuite/
* ld-aarch64/sframe-simple-1.d: Update expected output to
include SFRAME_F_FDE_FUNC_START_ADDR_PCREL.
* ld-x86-64/sframe-ibt-plt-1.d: Likewise.
* ld-x86-64/sframe-plt-1.d: Likewise.
* ld-x86-64/sframe-pltgot-1.d: Likewise.
* ld-x86-64/sframe-pltgot-2.d: Likewise.
* ld-x86-64/sframe-simple-1.d: Likewise.
Naturally, the change of semantics for 'SFrame FDE function start address'
has consequences on the implementation in libsframe. As per the new
semantics:
- Function start address in the SFrame FDE (sfde_func_start_address)
is an offset from the FDE function start address field to the start
PC of the associated function.
Note that, the libsframe library brings the SFrame section contents into
its own memory to create a sframe_decoder_ctx object via sframe_decode
(). Many internal and user-interfacing APIs then use sframe_decoder_ctx
object to interact and fulfill the work.
In context of changing semantics for sfde_func_start_address, following
relevant examples may help understand the impact:
- sframe_find_fre () finds a the SFrame stack trace data (SFrame FRE)
given a lookup offset (offset of lookup_pc from the start of SFrame
section). Now that the sfde_func_start_address includes the
distance from the sfde_func_start_address field to the start of
SFrame section itself, the comparison checks of
sfde_func_start_address with the incoming lookup offset need
adjustment.
- Some internal functions (sframe_get_funcdesc_with_addr_internal ()
finds SFrame FDE by using binary seach comparing
sfde_func_start_address fields, etc.) need adjustments.
- sframe_encoder_write () sorts the SFrame FDEs before writing out
the SFrame data. Sorting of SFrame FDE via the internal function
sframe_sort_funcdesc() needs adjustments: the new encoding of
sfde_func_start_address means the distances are not from the same
anchor, so cannot be sorted directly.
This patch takes the approach of adding a new internal function:
- sframe_decoder_get_secrel_func_start_addr (): This function returns
the offset of the start PC of the function from the start of SFrame
section, i.e., it gives a section-relative offset.
As the sframe_decoder_get_secrel_func_start_addr () API needs the value
of the function index in the FDE list, another internal API needs
sframe_fre_check_range_p () adjustments too.
Sorting the FDEs (via sframe_sort_funcdesc ()) is done by first bringing
all offsets in sfde_func_start_address relative to start of SFrame
section, followed by sorting, and then readjusting the offsets accroding
to the new position in the FDE list.
libsframe/
* sframe.c (sframe_decoder_get_secrel_func_start_addr): New
static function.
(sframe_fre_check_range_p): Adjust the interface a bit.
(sframe_get_funcdesc_with_addr_internal): Use
sframe_decoder_get_secrel_func_start_addr () when comparing
sfde_func_start_address with user input offset.
(sframe_find_fre): Adopt the new semantics.
(sframe_sort_funcdesc): Likewise.
For the libsframe testsuite, use the new encoding for FDE func start
addr: distance between the FDE sfde_func_start_address field and the
start PC of the function itself.
Use SFRAME_F_FDE_FUNC_START_ADDR_PCREL flag, though the sframe_encode ()
interface in libsframe applies no sanity checks for the encoding itself.
libsframe/testsuite/
* libsframe.find/findfre-1.c: Adjust to use the new
SFRAME_F_FDE_FUNC_START_ADDR_PCREL specific encoding.
* libsframe.find/findfunc-1.c: Likewise.
* libsframe.find/plt-findfre-1.c: Likewise.
* libsframe/testsuite/libsframe.decode/DATA2: Update data file
due to usage of new SFRAME_F_FDE_FUNC_START_ADDR_PCREL flag.
* libsframe/testsuite/libsframe.encode/encode-1.c: Use flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL.
---
[Changes in V4]
- Define new SFRAME_F_LD_MUSTHAVE_FLAGS. This will be the set of
flags that must be the same for all input SFrame decoder objects and
output SFrame encoder object.
- Use condensed form of check "(dctx_flags ^ ectx_flags) &
SFRAME_F_LD_MUSTHAVE_FLAGS" to enforce that decoder and encoder
flags are harmonious.
- Update commit log to weave in SFRAME_F_LD_MUSTHAVE_FLAGS.
- Add explicit check in sframe_encode () for the flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL to be set. The write APIs of the
SFrame encoder object are doing the right thing only for the case
when SFRAME_F_FDE_FUNC_START_ADDR_PCREL is set.
- Explicitly set SFRAME_F_FDE_FUNC_START_ADDR_PCREL before call to
sframe_encode () in _bfd_elf_merge_section_sframe ().
- Fix encode-1.c testcase to use SFRAME_F_FDE_FUNC_START_ADDR_PCREL
flag. This was uncovered due to the changes related to usage of
SFRAME_F_FDE_FUNC_START_ADDR_PCREL for invocation of and inside
sframe_encode ().
- Update code comments on why special handling of SFRAME_F_FDE_SORTED
before sframe_encode () call in _bfd_elf_merge_section_sframe ().
- Removed the TBD for libsframe versioning. The plan is to create a
LIBSFRAME_2.0 {
global:
sframe_decoder_get_flags;
sframe_decoder_get_offsetof_fde_start_addr;
sframe_encoder_get_flags;
sframe_encoder_get_offsetof_fde_start_addr;
... // list all the APIs.
};
before the 2.45 release.
[End of changes in V4]
[No changes in V3]
[No changes in V2]
|
|
PR libsframe/32589 - function start address is zero in SFrame section dump
Currently, readelf and objdump display the SFrame sections in ET_REL
object files with function start addresses of each function as 0. This
makes it difficult to correlate SFrame stack trace information with the
individual functions in the object file.
For objdump, use the dump_dwarf () interface to dump SFrame section.
Similarly, for readelf, use the display_debug_section () interface to
dump SFrame section. These existing interfaces (for DWARF debug
sections) already support relocating the section contents before
dumping, so lets use them for SFrame sections as well.
When adding a new entry for SFrame in debug_option_table[], use char
'nil' and the option name of "sframe-internal-only". This is done so
that there is no additional (unnecessary) user-exposed ways of dumping
SFrame sections. Additionally, we explicitly disallow the
"sframe-internal-only" from external/user input in --dwarf (objdump).
Similarly, "sframe-internal-only" is explicitly matched and disallowed
from --debug-dump (readelf).
For objdump and readelf, we continue to keep the same error messaging as
earlier:
$ objdump --sframe=sframe bubble_sort.o
...
No sframe section present
$ objdump --sframe=.sfram bubble_sort.o
...
No .sfram section present
$ objdump --sframe=sframe-internal-only sort
...
No sframe-internal-only section present
Similarly for readelf:
$ readelf --sframe= bubble_sort.o
readelf: Error: Section name must be provided
$ readelf --sframe=.sfram bubble_sort.o
readelf: Warning: Section '.sfram' was not dumped because it does not exist
$ readelf --sframe=sframe bubble_sort.o
readelf: Warning: Section 'sframe' was not dumped because it does not exist
PS: Note how this patch adds a new entry to debug_displays[] with a
relocate value set to FALSE. This will be set to TRUE in a subsequent
patch ("bfd: gas: ld: libsframe: emit func start addr field as an offset
from FDE") when fixes are made to emit the value of the
'sfde_func_start_address' field in the new encoding
SFRAME_F_FDE_FUNC_START_ADDR_PCREL across gas and ld.
binutils/
* dwarf.c (display_sframe): New definition.
(dwarf_select_sections_all): Enable SFrame section too.
(struct dwarf_section_display): Add entry for SFrame section.
* dwarf.h (enum dwarf_section_display_enum): Add enumerator for
SFrame.
* objdump.c (dump_section_sframe): Remove.
(dump_sframe_section): Add new definition.
(dump_bfd): Use dump_sframe_section.
* binutils/readelf.c (dump_section_as_sframe): Remove.
---
This patch was previously reviewed at part of other series previously:
https://inbox.sourceware.org/binutils/20250308073853.78738-3-indu.bhagat@oracle.com/
The review comments have been addressed in this patch. The setting of
relocate to FALSE for the new record is the new diff.
{ { ".sframe", "", "", NO_ABBREVS }, display_sframe, &do_sframe, false },
This is necessary to keep each patch in the series bisectable and reviewable.
Notes:
- V3 was OK'd https://sourceware.org/pipermail/binutils/2025-June/141796.html
[No changes in V4]
[No changes in V3]
[No changes in V2]
|
|
Add a new flag SFRAME_F_FDE_FUNC_START_ADDR_PCREL to SFrame stack trace
format. If set, this flag indicates that the function start address
field (sfde_func_start_address) is the offset to the function start
address from the SFrame FDE function start address field itself.
Such an encoding is friendlier to the exisitng PC-REL relocations
available in the ABIs supported in SFrame: AMD64 (R_X86_64_PC32) and
AArch64 (R_AARCH64_PREL32). In subsequent patches, we will make the
implementation in gas and ld to both:
- emit the values in the same (above-mentioned) encoding uniformly.
- set the flag SFRAME_F_FDE_FUNC_START_ADDR_PCREL in the SFrame header
for consumers to be able to distinguish.
Define SFRAME_F_ALL_FLAGS in sframe-api.h to help keep the
implementation less error-prone by keeping a set of all defined flags at
a central place. Adjust the check in sframe_header_sanity_check_p () to
use the SFRAME_F_ALL_FLAGS instead.
Add documentation for SFRAME_F_FDE_FUNC_START_ADDR_PCREL. Update the
documentation about the encoding of the sfde_func_start_address field.
Also, update the section "Changes from Version 1 to Version 2" to
include the specification of the new flag
SFRAME_F_FDE_FUNC_START_ADDR_PCREL as an errata release to the SFrame
Version 2 specification.
include/
* sframe-api.h (SFRAME_F_ALL_FLAGS): New definition.
* sframe.h (SFRAME_F_FDE_FUNC_START_ADDR_PCREL): Likewise.
libsframe/
* sframe-dump.c (dump_sframe_header_flags): Update to include
the new flag.
* sframe.c (sframe_header_sanity_check_p): Use uint8_t.
libsframe/doc/
* sframe-spec.texi: Add details about the new flag. Also update
the defails about the sfde_func_start_address encoding.
---
[Changes in V4]
- Define new SFRAME_F_ALL_FLAGS in sframe-api.h. Use it in
sframe_header_sanity_check_p (). Mention SFRAME_F_ALL_FLAGS in the
commit log.
- Add one liner in the SFrame spec "Bits corresponding to the currently
undefined flags must be set to zero."
[End of changes in V4]
[No changes in V3]
[Changes in V2]
- Switch back to the old style of flag values.
- Merge three patches from V1 into a single patch
include: libsframe: add APIs for offsetof FDE func start addr field
doc: sframe: add documentation for SFRAME_F_FDE_FUNC_START_ADDR_PCREL
doc: sframe: update documentation for sfde_func_start_address
[End of changes in V2]
|
|
These APIs will be later used by the linker to arrange SFrame FDEs in
the output SFrame section.
include/
* sframe-api.h (sframe_decoder_get_offsetof_fde_start_addr): New
declaration.
(sframe_encoder_get_offsetof_fde_start_addr): Likewise.
libsframe/
* libsframe.ver: List the new APIs.
* sframe.c (sframe_decoder_get_offsetof_fde_start_addr): New
definition.
(sframe_encoder_get_offsetof_fde_start_addr): Likewise.
---
[No changes in V4]
[No changes in V3]
[Changes in V2]
- Keep the function level comments in sync.
- Use an additional offsetof to convey the semantics clearly.
[End of changes in V2]
|
|
To prepare code for accommodating new flag additions easily as the
format evolves.
libsframe/
* sframe-dump.c (SFRAME_HEADER_FLAGS_STR_MAX_LEN): Remove.
(dump_sframe_header_flags): .. to here. New definition.
(PRINT_FLAG): New definition.
(dump_sframe_header): Move some implementation from here ..
--
[No Changes in V4]
[Changes in V3]
- Adjust macro PRINT_FLAGS to use a single argument with #x to
stringize for printing.
- Add stub to emit residual flags if any.
[End of changes in V3]
[Changes in V2]
- Get rid of helper struct and #defines and use simpler style as used
in binutils/objdump.c
[End of changes in V2]
|
|
Add new APIs, one each for getting flags from the SFrame decoder and
SFrame encoder context objects respectively.
These will later be used by the linker to uniformly access the flags,
given the SFrame decoder and SFrame encoder objects.
Use the new API, where applicable, within libsframe.
include/
* sframe-api.h (sframe_decoder_get_flags): New declaration.
(sframe_encoder_get_flags): Likewise.
libsframe/
* libsframe.ver: List new APIs.
* sframe.c (sframe_decoder_get_flags): New definition.
(sframe_encoder_get_flags): Likewise.
(sframe_get_funcdesc_with_addr_internal): Use the new API.
(sframe_encoder_get_flags): Likewise.
(sframe_encoder_write_sframe): Likewise.
---
Notes:
V2 was OK'd with some suggested changes which were done in V3.
[No changes in V4]
[Changes in V3]
- Use const sframe_header * where applicable.
- Revert the change of local variable from 'unsigned char all_flags'
to 'uint8_t all_flags'.
[End of changes in V3]
[Changes in V2]
- Amend function level comments and keep them in sync between decl and
def.
[End of changes in V2]
|
|
This patch add support for FEAT_PoPS feature which can be enabled
through +pops command line flag.
This patch also adds support for following DC instructions and the
spec can be found here [1].
1. "dc cigdvaps" enabled on passing +memtag+pops command line flags.
2. "dc civaps" enabled on passing +pops command line flag.
[1]: https://developer.arm.com/documentation/ddi0601/2025-03/AArch64-Instructions?lang=en
|
|
After the last commit there were still a couple of calls to
m_stream->emit_style_escape in the pager_file class. As discussed in
the last commit, these are likely wrong, but I'd not been able to
produce any bugs because of them.
The reason why there are no bugs is that these calls are, I think,
entirely redundant. Consider this block:
if (m_wrap_column)
{
/* We are about to insert a newline at an historic
location in the WRAP_BUFFER. Before we do we want to
restore the default style. To know if we actually
need to insert an escape sequence we must restore the
current applied style to how it was at the WRAP_COLUMN
location. */
m_applied_style = m_wrap_style;
m_stream->emit_style_escape (ui_file_style ());
/* If we aren't actually wrapping, don't output
newline -- if chars_per_line is right, we
probably just overflowed anyway; if it's wrong,
let us keep going. */
m_stream->puts ("\n");
}
What we know (see previous commit) is that the call:
m_stream->emit_style_escape (ui_file_style ());
is dangerous as m_stream->m_applied_style is going to be out of sync
with its current state. Actually, m_stream->m_applied_style is likely
to be the default style as it is not updated elsewhere. So why does
this not cause problems?
Well, GDB's style output is always done in tightly scoped regions.
That means if we want to print some styled output, and then apply a
wrap point the code might look like this:
fprintf_styled (gdb_stdout, file_name_style, "some text");
gdb_stdout->wrap_here (4);
But, after printing 'some text', the style of gdb_stdout will have
returned to the default style.
My claim is that, whenever we encounter a wrap_here call, the stream
in question will _always_ have been returned to the default style.
This means that, in the block above, the call:
m_stream->emit_style_escape (ui_file_style ());
will never emit anything because it depends on a check against
m_stream->m_applied_style, which will always mean that the above call
does nothing. But that's OK. By chance, we'll have always placed the
stream into a default style state anyway, so no harm done.
Similarly, the other call:
/* Having finished inserting the wrapping we should
restore the style as it was at the WRAP_COLUMN. */
m_stream->emit_style_escape (m_wrap_style);
Tries to return m_stream to the state it was in at the point of the
wrap_here call. But, as described above, this will always be the
default style, so the above call will do nothing, but that just
happens to be exactly what we want!
So what does this commit do?
Well, I "fix" the above code by removing the
m_stream->emit_style_escape calls and replacing them with calls to
puts, passing in the escape sequence for the required style, but only
if the m_stream style as tracked by pager_file::m_stream_style
indicates this is needed.
Got the reasons given above, this should mean there is no change after
this patch. We still shouldn't be emitting any extra escape
sequences. But, should we ever manage to get into a state where we
call wrap_here with a stream in a style other than the default, then
this should mean things work as expected.
There should be no user visible changes after this commit.
Approved-By: Tom Tromey <tom@tromey.com>
|
|
This commit fixes a couple of issues relating to the pagination
prompt and styling. The pagination prompt is this one:
--Type <RET> for more, q to quit, c to continue without paging--
I did try to split this into multiple patches, based on the three
issues I describe below, but in the end, the fixes were all too
interconnected, so it ended up as one patch that makes two related,
but slightly different changes:
1. Within the pager_file class, relying on the m_applied_style
attribute of the wrapped m_stream, as is done when calling
m_stream->emit_style_escape, is not correct, so stop doing that, and
2. Failing to update m_applied_style within the pager_file class can
leave that attribute out of date, which can then lead to styling
errors later on, so ensure m_applied_style is always updated.
The problems I have seen are:
1. After quitting from a pagination prompt, the next command can
incorrectly style its output. This was reported as bug PR
gdb/31033, and is fixed by this commit.
2. The pagination prompt itself could be styled. The pagination
prompt should always be shown in the default style.
3. After continuing the output at a pagination prompt, GDB can fail
to restore the default style the next time the output (within the
same command) switches back to the default style.
There are tests for all these issues as part of this patch.
The pager_file class is a sub-class of wrapped_file, this means that a
pager_file is itself a ui_file, while it also manages a pointer to a
ui_file object (called m_stream). An instance of pager_file can be
installed as the gdb_stdout ui_file object.
Output sent to a pager_file is stored within an internal
buffer (called m_wrap_buffer) until we have a complete line, when the
content is flushed to the wrapped m_stream. If sufficient lines have
been written out then the pager_file will present the pagination
prompt and allow the user to continue viewing output, or quit the
current command.
As a pager_file is a ui_file, it has an m_applied_style member
variable.
The managed stream (m_stream) is also a ui_file, and so also has an
m_applied_style member variable.
In some places within the pager_file class we attempt to change the
current style of the m_stream using calls like this:
m_stream->emit_style_escape (style);
See pager_file::emit_style_escape, pager_file::prompt_for_continue,
and pager_file::puts. These calls will end up in
ui_file::emit_style_escape, which tries to skip emitting unnecessary
style escapes by checking if the requested style matches the current
m_applied_style value.
The m_applied_style value is updated by calls to the emit_style_escape
function.
The problem here is that most of the time pager_file doesn't change
the style of m_stream by calling m_stream->emit_style_escape. Most of
the time, style changes are performed by pager_file writing the escape
sequence into m_wrap_buffer, and then later flushing this buffer to
m_stream by calling m_stream->puts.
It has to be done this way. Calling m_stream->emit_style_escape
would, if it actually changed the style, immediately change the style
by emitting an escape sequence. But pager_file doesn't want that, it
wants the style change to happen later, when m_wrap_buffer is
flushed.
To avoid excessive style escape sequences being written into
m_wrap_buffer, the pager_file::m_applied_style performs a function
similar to the m_applied_style within m_stream, it tracks the current
style for the end of m_wrap_buffer, and only allows style escape
sequences to be emitted if the style is actually changing.
However, a consequence of this is the m_applied_style within m_stream,
is not updated, which means it will be out of sync with the actual
current style of m_stream. If we then try to make a call to
m_stream->emit_style_escape, if the style we are changing too happens
to match the out of date style in m_stream->m_applied_style, then the
style change will be ignored.
And this is indeed what we see in pager_file::prompt_for_continue with
the call:
m_stream->emit_style_escape (ui_file_style ());
As m_stream->m_applied_style is not being updated, it will always be
the default style, however m_stream itself might not actually be in
the default style. This call then will not emit an escape sequence as
the desired style matches the out of date m_applied_style.
The fix in this case is to call m_stream->puts directly, passing in
the escape sequence for the desired style. This will result in an
immediate change of style for m_stream, which fixes some of the
problems described above.
In fact, given that m_stream's m_applied_style is always going to be
out of sync, I think we should change all of the
m_stream->emit_style_escape calls to instead call m_stream->puts.
However, just changing to use puts doesn't fix all the problems.
I found that, if I run 'apropos time', then quit at the first
pagination prompt. If for the next command I run 'maintenance time' I
see the expected output:
"maintenance time" takes a numeric argument.
However, everything after the first double quote is given the command
name style rather than only styling the text between the double
quotes.
Here is GDB's stack while printing the above output:
#2 0x0000000001050d56 in ui_out::vmessage (this=0x7fff1238a150, in_style=..., format=0x1c05af0 "", args=0x7fff1238a288) at ../../src/gdb/ui-out.c:754
#3 0x000000000104db88 in ui_file::vprintf (this=0x3f9edb0, format=0x1c05ad0 "\"%ps\" takes a numeric argument.\n", args=0x7fff1238a288) at ../../src/gdb/ui-file.c:73
#4 0x00000000010bc754 in gdb_vprintf (stream=0x3f9edb0, format=0x1c05ad0 "\"%ps\" takes a numeric argument.\n", args=0x7fff1238a288) at ../../src/gdb/utils.c:1905
#5 0x00000000010bca20 in gdb_printf (format=0x1c05ad0 "\"%ps\" takes a numeric argument.\n") at ../../src/gdb/utils.c:1945
#6 0x0000000000b6b29e in maintenance_time_display (args=0x0, from_tty=1) at ../../src/gdb/maint.c:128
The interesting frames here are #3, in here `this` is the pager_file
for GDB's stdout, and this passes its m_applied_style to frame #2 as
the `in_style` argument.
If the m_applied_style is wrong, then frame #2 will believe that the
wrong style is currently in use as the default style, and so, after
printing 'maintenance time' GDB will switch back to the wrong style.
So the question is, why is pager_file::m_applied_style wrong?
In pager_file::prompt_for_continue, there is an attempt to switch back
to the default style using:
m_stream->emit_style_escape (ui_file_style ());
If this is changed to a puts call (see above) then this still leaves
pager_file::m_applied_style out of date.
The right fix in this case is, I think, to instead do this:
this->emit_style_escape (ui_file_style ());
this will update pager_file::m_applied_style, and also send the
default style to m_stream using a puts call.
While writing the tests I noticed that I was getting unnecessary style
reset sequences emitted.
The problem is that, around pagination, we don't really know what
style is currently applied to m_stream. The
pager_file::m_applied_style tracks the style at the end of
m_wrap_buffer, but this can run ahead of the current m_stream style.
For example, if the screen is currently full, such that the next
character of output will trigger the pagination prompt, if the next
call is actually to pager_file::emit_style_escape, then
pager_file::m_applied_style will be updated, but the style of m_stream
will remain unchanged. When the next character is written to
pager_file::puts then the pagination prompt will be presented, and GDB
will try to switch m_stream back to the default style. Whether an
escape is emitted or not will depend on the m_applied_style value,
which we know is different than the actual style of m_stream.
It is, after all, only when m_wrap_buffer is flushed to m_stream that
the style of m_stream actually change.
And so, this commit also adds pager_file::m_stream_style. This new
variable tracks the current style of m_stream. This really is a
replacement for m_stream's ui_file::m_applied_style, which is not
accessible from pager_file.
When content is flushed from m_wrap_buffer to m_stream then the
current value of pager_file::m_applied_style becomes the current style
of m_stream. But, when m_wrap_buffer is filling up, but before it is
flushed, then pager_file::m_applied_style can change, but
m_stream_style will remain unchanged.
Now in pager_file::emit_style_escape we are able to skip some of the
direct calls to m_stream->puts() used to emit style escapes.
After all this there are still a few calls to
m_stream->emit_style_escape(). These are all in the wrap_here support
code. I think that these calls are technically broken, but don't
actually cause any issues due to the way styling works in GDB. I
certainly haven't been able to trigger any bugs from these calls yet.
I plan to "fix" these in the next commit just for completeness.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31033
Approved-By: Tom Tromey <tom@tromey.com>
|
|
On openSUSE Tumbleweed (with python 3.13), I get:
...
(gdb) PASS: gdb.python/py-warning.exp: python gdb.warning("")
python gdb.warning()^M
Python Exception <class 'TypeError'>: \
function missing required argument 'text' (pos 1)^M
Error occurred in Python: function missing required argument 'text' (pos 1)^M
(gdb) PASS: gdb.python/py-warning.exp: python gdb.warning()
...
But on openSUSE Leap 15.6 (with python 3.6), I get instead:
...
(gdb) PASS: gdb.python/py-warning.exp: python gdb.warning("")
python gdb.warning()^M
Python Exception <class 'TypeError'>: \
Required argument 'text' (pos 1) not found^M
Error occurred in Python: Required argument 'text' (pos 1) not found^M
(gdb) FAIL: gdb.python/py-warning.exp: python gdb.warning()
...
Fix this by updating the regexp.
Tested on x86_64-linux.
PR testsuite/33104
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33104
|
|
Disclaimer: this issue cannot occur with Object Attributes v1 (OAv1) while
using the GNU binutils because a value of '\0' (empty string) for a tag
with a string value is considered as the default value for the attribute,
and consequently is eliminated by gas from the output object file during
the serialization.
An empty string is a valid value for a NTBS tag in both OAv1 and OAv2 [1]
cases. However, contrarily to OAv1, a OAv2 subsection can be required and
so, tags in this subsection might have to be present even if the value is
the default. To comply with this requirement, the OAv2 serializer won't
drop the default values.
In the case where a NTBS tag has the value '\0' and is last in the object
attributes section, the current code in readelf used for dumping the object
attributes incorrectly detects an overflow, and prints out an error message
for a corrupted string tag.
This patch fixes the detection of the overflow so that it now accept an
empty string in the last tag of the object attributes section.
It also fixes the previous tests for the empty NTBS case and the non-null
terminated string one. The fix was also tested in the context of OAv2's
patch series [1] where the issue was originally detected. No regression
was found.
[1]: https://inbox.sourceware.org/binutils/20250509151319.88725-1-matthieu
.longo@arm.com/
|
|
The current testsuite for gas/readelf lacked two tests for EABI build
attributes:
- one when the final attribute is an empty string.
- one when the final attribute is a string missing the NULL terminator.
Those two issues cannot occur with Object Attributes v1 (OAv1) sections
created by the GNU binutils. Indeed a value of '\0' (empty string) for a
tag with a string value is considered as the default value for the
attribute, and consequently is eliminated by Gas from the output object
file during the serialization.
However, readelf should be able to process correctly files of an unknown
origin that could contain those two use cases.
This patch adds the two tests mentioned above. The first one is marked
as XFAIL because the empty string is not processed correctly by readelf
when it is in the last position. The second one passes, but simply print
out "[...]" without mentioning that the NTBS is corrupted.
A following patch will fix the bug in readelf, and will amend the newly
introduced tests.
|
|
On x86_64-freebsd with test-case gdb.base/infcall-failure.exp I get:
...
(gdb) continue
Continuing.
Program received signal SIGSEGV, Segmentation fault.
Address not mapped to object.
0x0000000000400522 in func_segfault () at infcall-failure.c:24
24 return *p; /* Segfault here. */
Error in testing condition for breakpoint 2:
The program being debugged was signaled while in a function called from GDB.
GDB remains in the frame where the signal was received.
To change this behavior use "set unwind-on-signal on".
Evaluation of the expression containing the function
(func_segfault) will be abandoned.
When the function is done executing, GDB will silently stop.
(gdb) FAIL: $exp: target_async=on: target_non_stop=on: \
run_cond_hits_segfault_test: continue
...
The problem is that the regexp in the test-case doesn't expect the
"Address not mapped to object." bit.
Fix this by updating the regexp.
Approved-by: Kevin Buettner <kevinb@redhat.com>
Tested on x86_64-freebsd and x86_64-linux.
|
|
|
|
This patch adds support for the RISC-V Profiles RVA23S64 and RVB23S64.
Version log:
Fix wrong test for rvb23s.
bfd/ChangeLog:
* elfxx-riscv.c: New Profiles.
gas/ChangeLog:
* testsuite/gas/riscv/attribute-rva23s.d: New test.
* testsuite/gas/riscv/attribute-rvb23s.d: New test.
|
|
PR testsuite/31831 reports the following failure in the
gdb.dap/log-message.exp test-case (formatted for readability):
...
{ "type": "event",
"event": "output",
"body": {
"category": "stdout",
"output": "Breakpoint 1 at 0x681: file log-message.c, line 23.\n"
},
"seq": 13
}
FAIL: $exp: logging output (checking body category)
...
for a gdb 14.2 based package.
The output event listed above is a result from the setBreakpoints request.
The test-case issues the setBreakpoints request and waits for the
corresponding response, but doesn't wait for the output event, and
consequently the output event is read by:
...
dap_wait_for_event_and_check "logging output" output \
{body category} console \
{body output} "got 23 - 23 = 0"
...
which triggers the failure.
I'm not able to reproduce this, but it looks worth fixing regardless.
We're fixing this on trunk though, and the output event looks different, and
there's one more output event:
...
{ "type": "event",
"event": "output",
"body": {
"category": "stdout",
"output": "No source file named log-message.c.\n"
},
"seq": 4
}
{ "type": "event",
"event": "output",
"body": {
"category": "stdout",
"output": "Breakpoint 1 (-source log-message.c -line 23) pending.\n"
},
"seq": 5
}
...
Fix this by waiting for these two output events, making the test-case a bit
more robust.
It is possible that one or both of these output events will be read by
dap_check_request_and_response "set breakpoint", and in that case restashing
them (for which there's currently no infrastructure) would be an easy way of
handling this. But I haven't been able to trigger that, so I'm leaving that
for if and when it does.
Tested on x86_64-linux.
Approved-By: Tom Tromey <tom@tromey.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31831
|
|
A user pointed out that DAP allows the "threads" request to work when
the inferior is running. This is documented in the overview, not the
specification.
While looking into this, I found a few other issues:
* The _thread_name function was not marked @in_gdb_thread.
This isn't very important but is still an oversight.
* DAP requires all threads to have a name -- the field is not optional
in the "Thread" type.
* There was no test examining events resulting from the inferior
printing to stdout.
This patch fixes all these problems.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33080
|
|
I changed my system linker to 'mold', but then I saw some gdb test
failures. This patch fixes a subset of the failures.
dw2-strp.exp was failing, and investigating showed that there were two
.debug_str sections. I tracked this down to the .S file not using the
correct section flags.
This patch fixes this problem, plus the other instances I could find.
(Strangely, these did not all cause problems, however.) I also
changed the DWARF assembler to always use these flags for .debug_str.
|
|
Split -v from -version/--version. They aren't the same; -v long form is
--verbose, which so far wasn't mentioned at all.
|
|
Update the Profiles string in RV23 to include the extensions 'b' and 'supm'.
bfd/ChangeLog:
* elfxx-riscv.c: Update Profiles string in RV23.
gas/ChangeLog:
* testsuite/gas/riscv/attribute-19.d: Update test string.
* testsuite/gas/riscv/attribute-20.d: Ditto.
|
|
|
|
|
|
|
|
This patch adds support for generating unlabeled landing pad PLT entries
for the RISC-V architecture. Unlabeled landing pad will place a LPAD
instruction at the PLT entry and PLT header, also PLT header will have
few changes due to the offset is different from the original one.
Ref: https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/417
|
|
GNU_PROPERTY_RISCV_FEATURE_1_AND will perform a bitwise AND operation
on the properties of the input files.
|
|
GNU_PROPERTY_RISCV_FEATURE_1_CFI_LP_UNLABELED
This patch adds two new GNU properties for RISC-V:
GNU_PROPERTY_RISCV_FEATURE_1_CFI_SS and GNU_PROPERTY_RISCV_FEATURE_1_CFI_LP_UNLABELED.
We only add readelf and define the properties in this patch.
Ref: https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/417
|
|
The goal of this refactor is to improve the possiblity of having
different PLT generation code for different RISC-V ABIs. The changes
include:
- Extract PLT generation logic into individual functions.
- Keep the PLT generation data in riscv_elf_link_hash_table.
In the following patches, we will use this framework to implement
different PLT.
|
|
|
|
Make sure we bail out early from amd64_analyze_prologue if CURRENT_PC
is reached to avoid unnecessary call to amd64_analyze_frame_setup.
Approved-By: Andrew Burgess <aburgess@redhat.com>
|
|
Compilers can put a sequence aligning the stack at the entry of a
function. However with -fcf-protection enabled, "endbr64" is
generated before. Current implementation of amd64 prologue analyzer
first checks for stack alignment and then for "endbr64", which is not
correct. This behavior was introduced with patch "gdb: handle endbr64
instruction in amd64_analyze_prologue". In case both are generated,
prologue will not be skipped. This patch swaps the order so that
"endbr64" is checked first and adds a regression test. i386-tdep
implementation also already had those checked in the correct order,
that is stack alignment is after endbr64.
Given such source compiled with gcc 11.4.0 via:
gcc -O0 main.c -o main
```
#include <alloca.h>
void
foo (int id)
{
volatile __attribute__ ((__aligned__ (64))) int a;
volatile char *p = (char *) alloca (id * 12);
p[2] = 'b';
}
int
main (int argc, char **argv)
{
foo (argc + 1);
return 1;
}
```
we get such function entry for foo (generated with objdump -d):
```
0000000000001149 <foo>:
1149: f3 0f 1e fa endbr64
114d: 4c 8d 54 24 08 lea 0x8(%rsp),%r10
1152: 48 83 e4 c0 and $0xffffffffffffffc0,%rsp
1156: 41 ff 72 f8 push -0x8(%r10)
115a: 55 push %rbp
115b: 48 89 e5 mov %rsp,%rbp
115e: 41 52 push %r10
1160: 48 81 ec a8 00 00 00 sub $0xa8,%rsp
1167: 89 7d 8c mov %edi,-0x74(%rbp)
...
```
The 3 instructions following endbr64 align the stack. If we were to set
a breakpoint on foo, gdb would set it at function's entry:
```
(gdb) b foo
Breakpoint 1 at 0x1149
(gdb) r
...
Breakpoint 1, 0x0000555555555149 in foo ()
(gdb) disassemble
Dump of assembler code for function foo:
=> 0x0000555555555149 <+0>: endbr64
0x000055555555514d <+4>: lea 0x8(%rsp),%r10
0x0000555555555152 <+9>: and $0xffffffffffffffc0,%rsp
0x0000555555555156 <+13>: push -0x8(%r10)
0x000055555555515a <+17>: push %rbp
0x000055555555515b <+18>: mov %rsp,%rbp
0x000055555555515e <+21>: push %r10
0x0000555555555160 <+23>: sub $0xa8,%rsp
0x0000555555555167 <+30>: mov %edi,-0x74(%rbp)
...
```
With this patch fixing the order of checked instructions, gdb can
properly analyze the prologue:
```
(gdb) b foo
Breakpoint 1 at 0x115e
(gdb) r
...
Breakpoint 1, 0x000055555555515e in foo ()
(gdb) disassemble
Dump of assembler code for function foo:
0x0000555555555149 <+0>: endbr64
0x000055555555514d <+4>: lea 0x8(%rsp),%r10
0x0000555555555152 <+9>: and $0xffffffffffffffc0,%rsp
0x0000555555555156 <+13>: push -0x8(%r10)
0x000055555555515a <+17>: push %rbp
0x000055555555515b <+18>: mov %rsp,%rbp
=> 0x000055555555515e <+21>: push %r10
0x0000555555555160 <+23>: sub $0xa8,%rsp
0x0000555555555167 <+30>: mov %edi,-0x74(%rbp)
...
```
Approved-By: Andrew Burgess <aburgess@redhat.com>
|
|
Refactor amd64_analyze_prologue so it clearly reflects what is the order
of operations in the prologue that we expect to encounter, as is the
case for i386's implementation.
Approved-By: Andrew Burgess <aburgess@redhat.com>
|
|
Update the make-check-all.sh script to use TESTS rather than passing
the test names within RUNTESTFLAGS. This addresses the following
issue:
I was running some tests like this:
make -C gdb check-all-boards TESTS="gdb.base/break*.exp"
And I was finding that I would get lots of DUPLICATE test results,
which is not what I expected.
What's happening here is that the 'make check-all-boards' rule runs
the 'make-check-all.sh' script, which then runs 'make check' with
various board files.
However, passing TESTS=... to the initial 'make check-all-boards'
command invocation automatically causes the TESTS value to be added to
the MAKEFLAGS environment variable, this is then picked up by the
later calls to 'make check'.
Now, in GDB's testfile/Makefile, we check for TESTS, and if this is
set, we expand the value and set `expanded_tests_or_none`. Otherwise,
if TESTS is not set, expanded_tests_or_none is left empty.
Finally, when handling 'make check', the value of
`expanded_tests_or_none` is passed through to dejagnu, along with the
RUNTESTFLAGS value.
What this means is that, when make-check-all.sh passes the test names
in the RUNTESTFLAGS, then dejagnu ends up seeing the list of tests
twice, once from RUNTESTFLAGS, and once from expanded_tests_or_none,
and this is why I was seeing duplicate testnames.
The easiest fix for the above is to have make-check-all.sh pass the
test names using TESTS="...", this will override the TESTS="..." value
already present in MAKEFLAGS, and means dejagnu will see the test
names just once.
Additionally, this is a start towards allowing parallel test running
from the make-check-all.sh script. Parallel test running only works
if the test names are passed in TESTS, and not in RUNTESTFLAGS.
Currently, in testsuite/Makefile, if RUNTESTFLAGS is not empty, then
we force single threaded test running. But with this change, at least
for the `local` board, we can now benefit from multi-threaded test
running, as this board has an empty RUNTESTFLAGS now. For the other
boards we'd need to set FORCE_PARALLEL in order to benefit from
parallel test running, but we'll need to double check that all the
board files actually support parallel test running first, so I'm
leaving that for another day.
|
|
Since the output section contents are copied from the input, don't
extend the output section size beyond the input section size.
PR binutils/33049
* objcopy.c (copy_section): Don't extend the output section
size beyond the input section size.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
|
|
Report corrupted group section instead of trying to recover.
PR binutils/33050
* elf.c (bfd_elf_set_group_contents): Report corrupted group
section.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
|
|
This commit adds filename completion for the shell command part of
the pipe command. This is a follow on from this commit:
commit 036e5c0c9121d0ac691dbf408a3bdf2bf3501d0f
Date: Mon May 19 20:54:54 2025 +0100
gdb: use quoted filename completion for the shell command
which fixed the completion for the 'shell' command itself.
Like with the 'shell' command, we don't offer completions of command
names pulled from $PATH, we just offer filename completion, which is
often useful for arguments being passed to commands. Maybe in the
future we could add completion for command names too (for both 'pipe'
and the 'shell' command), but that is left for a future commit.
There's some additional testing.
|
|
The use of user namespaces is required for normal users to use mount
namespaces. Consider trying this as an unprivileged user:
$ unshare --mount /bin/true
unshare: unshare failed: Operation not permitted
The problem here is that an unprivileged user doesn't have the
required permissions to create a new mount namespace. If, instead, we
do this:
$ unshare --mount --map-root-user /bin/true
then this will succeed. The new option causes unshare to create a
user namespace in which the unprivileged user is mapped to UID/GID 0,
and so gains all privileges (inside the namespace), the user is then
able to create the mount namespace as required.
So, how does this relate to GDB?
When a user attaches to a process running in a separate mount
namespace, GDB makes use of a separate helper process (see
linux_mntns_get_helper in nat/linux-namespaces.c), which will then use
the `setns` function to enter (or try to enter) the mount namespace of
the process GDB is attaching too. The helper process will then handle
file I/O requests received from GDB, and return the results back to
GDB, this allows GDB to access files within the mount namespace.
The problem here is that, switching to a mount namespace requires that
a process hold CAP_SYS_CHROOT and CAP_SYS_ADMIN capabilities within
its user namespace (actually it's a little more complex, see 'man 2
setns'). Assuming GDB is running as an unprivileged user, then GDB
will not have the required permissions.
However, if GDB enters the user namespace that the `unshare` process
created, then the current user will be mapped to UID/GID 0, and will
have the required permissions.
And so, this patch extends linux_mntns_access_fs (in
nat/linux-namespace.c) to first try and switch to the user namespace
of the inferior before trying to switch to the mount namespace. If
the inferior does have a user namespace, and does have elevated
privileges within that namespace, then this first switch by GDB will
mean that the second step, into the mount namespace, will succeed.
If there is no user namespace, or the inferior doesn't have elevated
privileges within the user namespace, then the switch into the mount
namespace will fail, just as it currently does, and the user will need
to give elevated privileges to GDB via some other mechanism (e.g. run
as root).
This work was originally posted here:
https://inbox.sourceware.org/gdb-patches/20230321120126.1418012-1-benjamin@sipsolutions.net
I (Andrew Burgess) have made some cleanups to the code to comply with
GDB's coding standard, and the test is entirely mine. This commit
message is also entirely mine -- the original message was very terse
and required the reader to understand how the various namespaces
work and interact. The above is my attempt to document what I now
understand about the problem being fixed.
I've left the original author in place as the core of the GDB change
itself is largely as originally presented, but any inaccuracies in the
commit message, or problems with the test, are all mine.
Co-Authored-by: Andrew Burgess <aburgess@redhat.com>
|
|
This commit works around a problem introduced by commit:
commit e58beedf2c8a1e0c78e0f57aeab3934de9416bfc
Date: Tue Jan 23 16:00:59 2024 +0000
gdb: attach to a process when the executable has been deleted
The above commit extended GDB for Linux, so that, of the executable
for a process had been deleted, GDB would instead try to use
/proc/PID/exe as the executable.
This worked by updating linux_proc_pid_to_exec_file to introduce the
/proc/PID/exe fallback. However, the result of
linux_proc_pid_to_exec_file is then passed to exec_file_find to
actually find the executable, and exec_file_find, will take into
account the sysroot. In addition, if GDB is attaching to a process in
a different MNT and/or PID namespace then the executable lookup is
done within that namespace.
This all means two things:
1. Just because linux_proc_pid_to_exec_file cannot see the
executable doesn't mean that GDB is actually going to fail to
find the executable, and
2. returning /proc/PID/exe isn't useful if we know GDB is then going
to look for this within a sysroot, or within some other
namespace (where PIDs might be different).
There was an initial attempt to fix this issue here:
https://inbox.sourceware.org/gdb-patches/20250511141517.2455092-4-kilger@sec.in.tum.de/
This proposal addresses the issue in PR gdb/32955, which is all about
the namespace side of the problem. The fix in this original proposal
is to check the MNT namespace inside linux_proc_pid_to_exec_file, and
for the namespace problem this is fine. But we should also consider
the sysroot problem.
And for the sysroot problem, the fix cannot fully live inside
linux_proc_pid_to_exec_file, as linux_proc_pid_to_exec_file is shared
between GDB and gdbserver, and gdbserver has no sysroot.
And so, I propose a slightly bigger change.
Now, linux_proc_pid_to_exec_file takes a flag which indicates if
GDB (or gdbserver) will look for the inferior executable in the
local file system, where local means the same file system as GDB (or
gdbserver) is running in.
This local file system check is true if:
1. The MNT namespace of the inferior is the same as for GDB, and
2. for GDB only, the sysroot must either be empty, or 'target:'.
If the local file system check is false then GDB (or gdbserver) is
going to look elsewhere for the inferior executable, and so, falling
back to /proc/PID/exe should not be done, as GDB will end up looking
for this file in the sysroot, or within the alternative MNT
namespace (which in also likely to be a different PID namespace).
Now this is all a bit of a shame really. It would be nice if
linux_proc_pid_to_exec_file could return /proc/PID/exe in such a way
that exec_file_find would know that the file should NOT be looked for
in the sysroot, or in the alternative namespace. But fixing that
problem would be a much bigger change, so for now lets just disable
the /proc/PID/exe fallback for cases where it might not work.
For testing, the sysroot case is now tested.
I don't believe we have any alternative namespace testing. It would
certainly be interesting to add some, but I'm not proposing any with
this patch, so the code for checking the MNT namespace has been tested
manually by me, but isn't covered by a new test I'm adding here.
Author of the original fix is listed as co-author here. Credit for
identifying the original problem, and proposing a solution belongs to
them.
Co-Authored-By: Fabian Kilger <kilger@sec.in.tum.de>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32955
|
|
Currently, when attaching to a process, if the user hasn't told GDB
which executable they are going to be debugging, GDB will try to
figure out the executable from the running process.
There are two (for this patch) interesting places where this can fail,
both in exec_file_locate_attach.
First GDB calls target_pid_to_exec_file, this does target specific
"stuff" to find the name of the executable file. If this returns NULL
then GDB will give a warning and return.
After this we need to "find" the executable. This is where we apply
things like the sysroot in order to transform the executable path.
This is done by calling exec_file_find, and this too can return NULL
to indicate that the executable couldn't be found.
Currently, if exec_file_find returns NULL then GDB doesn't give a
warning, instead we push on and call try_open_exec_file passing in the
NULL pointer as the filename string. This has the effect of removing
the current executable from the current program space.
However, exec_file_locate_attach already checks there is no executable
attached to the current program space. If there was, then there would
be no need to try and lookup the executable from the running process.
So calling try_open_exec_file with a NULL string is, I claim,
pointless.
But worse, calling try_open_exec_file with a NULL string means that
GDB prints the message: "No executable file now.", which, while
correct, isn't (I think) very helpful. To me this message indicates
that we've moved from a state of having an executable to a state of
not having one, which isn't correct.
I think we should introduce a new warning in exec_file_locate_attach,
which is printed if the executable cannot be found.
So, before this patch GDB's output looked like this:
(gdb) attach 12345
Attaching to process 12345
No executable file now.
warning: Could not load vsyscall page because no executable was specified
0x00007f0978b94557 in ?? ()
(gdb)
After this patch the output now looks like this:
(gdb) attach 12345
Attaching to process 12345
No executable has been specified, and target executable /tmp/my-exec (deleted) could not be found. Try using the "file" command.
warning: Could not load vsyscall page because no executable was specified
0x00007f0978b94557 in ?? ()
(gdb)
This warning includes the name of the file that GDB was looking for,
and gives a hint that the 'file' command should be used to tell GDB
which executable is being debugged. Much better.
There's no test for this change in this commit. The next commit fixes
another (semi-related) bug, and includes a test that checks for this
warning string.
|
|
Tom de Vries reported a build failure on x86_64-w64-mingw32 after
commit:
commit bd389c9515d240f55b117075b43184efdea41287
Date: Wed Jun 11 22:52:16 2025 +0200
gdb: implement linux namespace support for fileio_lstat and vFile::lstat
The build failure looks like this:
../../src/gdbserver/hostio.cc: In function 'void handle_lstat(char*, int*)':
../../src/gdbserver/hostio.cc:544:63: error: cannot convert '_stat64*' to 'stat*'
544 | ret = the_target->multifs_lstat (hostio_fs_pid, filename, &st);
| ^~~
| |
| _stat64*
In file included from ./../../src/gdbserver/server.h:58,
from <command-line>:
./../../src/gdbserver/target.h:448:74: note: initializing argument 3 of 'virtual int process_stratum_target::multifs_lstat(int, const char*, stat*)'
448 | virtual int multifs_lstat (int pid, const char *filename, struct stat *sb);
| ~~~~~~~~~~~~~^~
The problem is that in sys/stat.h for mingw, 'stat' is #defined to
_stat64, but target.h doesn't include sys/stat.h, and so doesn't see
this #define.
However, target.h does, by luck, manages to see the actual definition
of 'struct stat', which isn't in sys/stat.h itself, but is in some
other header that just happens to be pulled in by chance.
As a result of all this, the declaration of
process_stratum_target::multifs_lstat in target.h uses 'struct stat'
for its argument type, while the call in hostio.cc, uses 'struct
_stat64' as its argument type, which causes the build error seen
above.
The fix is to include sys/stat.h in target.h so that the declaration's
argument type will change to 'struct _stat64' (via the #define).
|
|
|
|
|
|
There are some OpenRISC CPUs that have their binaries stored in
little-endian format. Using objdump to disassemble these is
problematic, as some instructions fail to disassemble, for example:
objdump -D -b binary -EB -m or1k test_be.bin
0: 18 60 07 27 l.movhi r3,0x727
4: a8 63 0e 00 l.ori r3,r3,0xe00
8: 9c 63 ff ff l.addi r3,r3,-1
c: bc 43 00 00 l.sfgtui r3,0
10: 13 ff ff fe l.bf 0x8
14: 44 00 48 00 l.jr r9
objdump -D -b binary -EL -m or1k test_le.bin
0: 27 07 60 18 *unknown*
4: 00 0e 63 a8 l.ori r3,r3,0xe00
8: ff ff 63 9c *unknown*
c: 00 00 43 bc l.sfgtui r3,0
10: fe ff ff 13 *unknown*
14: 00 48 00 44 l.jr r9
It was found that the hash function was using the still little-endian
buffer to extract the opcode used for the hash lookup. This didn't work
as it was pulling the wrong hashcode causing instruction lookup to fail.
Fix the hash function by using the normalized/byte-swapped value instead
of the buffer.
Signed-off-by: Stafford Horne <shorne@gmail.com>
|
|
|
|
Theoretically, in functions core_addr_to_string_nz() and
core_addr_to_string(), strcat() can overflow, so use a safe
approach using xsnprintf().
Change-Id: Ib9437450b3634dc35077234f462a03a8640242d4
|
|
This patch simplifies the code at two points by removing redundant
null checks. There is no functional impact.
Reviewed-By: Keith Seitz <keiths@redhat.com>
Approved-By: Pedro Alves <pedro@palves.net>
Change-Id: I76e1c7fad00e8fcb24ced7bfd75d19cdd6266c32
|
|
This patch adds support for following system registers and the spec
can be found here[1].
1. PMBSR_EL12, PMBSR_EL2, PMBSR_EL3, PMBMAR_EL1 depends on FEAT_SPE
and Armv9.5-A architecture and these are enabled by passing
-march=armv9.5-a+profile.
2. TRBSR_EL12, TRBSR_EL2, and TRBSR_EL3 depends Armv9.5-A architecture
and these are enabled by passing -march=armv9.5-a.
3. HFGITR2_EL2 depends on Armv8.8-A architecture and enabled by passing
-march=armv8.8-a.
[1]: https://developer.arm.com/documentation/ddi0601/2025-03/AArch64-Registers?lang=en
|
|
Currently gdbserver uses the require_int() function to parse the
requested offset (in vFile::pread packet and the like). This function
allows integers up to 0x7fffffff (to fit in 32-bit int), however the
offset (for the pread system call) has an off_t type which can be
larger than 32-bit.
This patch allows require_int() function to parse offset up to the
maximum value implied by the off_t type.
Approved-By: Pedro Alves <pedro@palves.net>
Change-Id: I3691bcc1ab1838c0db7f8b82d297d276a5419c8c
|
