Commit graph

200 commits

Author SHA1 Message Date
Simon Marchi
05d9d66d92 gdb: remove unused includes in utils.h
Remove some includes reported as unused by clangd.  Add some includes in
other files that were previously relying on the transitive include.

Change-Id: Ibdd0a998b04d21362a20d0ca8e5267e21e2e133e
2024-05-30 22:43:52 -04:00
Simon Marchi
5b9707eb87 gdb: remove gdbcmd.h
Most files including gdbcmd.h currently rely on it to access things
actually declared in cli/cli-cmds.h (setlist, showlist, etc).  To make
things easy, replace all includes of gdbcmd.h with includes of
cli/cli-cmds.h.  This might lead to some unused includes of
cli/cli-cmds.h, but it's harmless, and much faster than going through
the 170 or so files by hand.

Change-Id: I11f884d4d616c12c05f395c98bbc2892950fb00f
Approved-By: Tom Tromey <tom@tromey.com>
2024-04-25 12:59:02 -04:00
Simon Marchi
18d2988e5d gdb, gdbserver, gdbsupport: remove includes of early headers
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them.  Remove all the inclusions of these files I could find.  Update
the generation scripts where relevant.

Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26 21:13:22 -04:00
Simon Marchi
6fdf95ae53 gdb: remove core_bfd macro
The core_bfd macro hides a use of current_program_space.  Remove it, so
that we have the opportunity to get the program space from the context,
if possible.  I guess that the macro was introduced at some point to
replace a global variable of the same name without changing all the
uses.

Change-Id: I971a65b29b5e5a5941f3cb7ea234547daa787268
Approved-By: Tom Tromey <tom@tromey.com>
2024-02-06 10:57:55 -05:00
Andrew Burgess
1d506c26d9 Update copyright year range in header of all files managed by GDB
This commit is the result of the following actions:

  - Running gdb/copyright.py to update all of the copyright headers to
    include 2024,

  - Manually updating a few files the copyright.py script told me to
    update, these files had copyright headers embedded within the
    file,

  - Regenerating gdbsupport/Makefile.in to refresh it's copyright
    date,

  - Using grep to find other files that still mentioned 2023.  If
    these files were updated last year from 2022 to 2023 then I've
    updated them this year to 2024.

I'm sure I've probably missed some dates.  Feel free to fix them up as
you spot them.
2024-01-12 15:49:57 +00:00
Tom Tromey
69f6730df3 Remove gdb_static_assert
C++17 makes the second parameter to static_assert optional, so we can
remove gdb_static_assert now.
2023-11-29 14:29:44 -07:00
Ilya Leoshkevich
fa1c74b22a gdb: Fix "target file /proc/.../cmdline contained unexpected null characters"
When using the gcore command, GDB prints the following warning:

    (gdb) gcore
    warning: target file /proc/.../cmdline contained unexpected null characters

The reason is that cmdline is read with target_fileio_read_stralloc(),
which warns on seeing null characters. However, it's perfectly valid
for cmdline to contain \0s, so switch to target_fileio_read_alloc().

Approved-By: Tom Tromey <tom@tromey.com>
2023-11-24 12:26:16 +01:00
Lancelot Six
8082468ffe gdb: Use std::string_view instead of gdb::string_view
Given that GDB now requires a C++17, replace all uses of
gdb::string_view with std::string_view.

This change has mostly been done automatically:
- gdb::string_view -> std::string_view
- #include "gdbsupport/gdb_string_view.h" -> #include <string_view>

One things which got brought up during review is that gdb::stging_view
does support being built from "nullptr" while std::sting_view does not.
Two places are manually adjusted to account for this difference:
gdb/tui/tui-io.c:tui_getc_1 and
gdbsupport/format.h:format_piece::format_piece.

The above automatic change transformed
"gdb::to_string (const gdb::string_view &)" into
"gdb::to_string (const std::string_view &)".  The various direct users
of this function are now explicitly including
"gdbsupport/gdb_string_view.h".  A later patch will remove the users of
gdb::to_string.

The implementation and tests of gdb::string_view are unchanged, they will
be removed in a following patch.

Change-Id: Ibb806a7e9c79eb16a55c87c6e41ad396fecf0207
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
2023-11-21 11:52:36 +00:00
Lancelot Six
6b09f1342c gdb: Replace gdb::optional with std::optional
Since GDB now requires C++17, we don't need the internally maintained
gdb::optional implementation.  This patch does the following replacing:
  - gdb::optional -> std::optional
  - gdb::in_place -> std::in_place
  - #include "gdbsupport/gdb_optional.h" -> #include <optional>

This change has mostly been done automatically.  One exception is
gdbsupport/thread-pool.* which did not use the gdb:: prefix as it
already lives in the gdb namespace.

Change-Id: I19a92fa03e89637bab136c72e34fd351524f65e9
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
2023-11-21 11:52:35 +00:00
Simon Marchi
aab2d3a649 gdb: use gdb::byte_vector instead of gdb::def_vector<gdb_byte>
Use the gdb::byte_vector typedef when possible.

Change-Id: Ib2199201c052496992011ea02979de023d4d8a9a
2023-11-01 13:06:13 -04:00
Simon Marchi
27b1f19f8f gdb: add inferior::{arch, set_arch}
Make the inferior's gdbarch field private, and add getters and setters.
This helped me by allowing putting breakpoints on set_arch to know when
the inferior's arch was set.  A subsequent patch in this series also
adds more things in set_arch.

Change-Id: I0005bd1ef4cd6b612af501201cec44e457998eec
Reviewed-By: John Baldwin <jhb@FreeBSD.org>
Approved-By: Andrew Burgess <aburgess@redhat.com>
2023-10-10 10:44:35 -04:00
Luis Machado
7070423f17 corefile/bug: Use thread-specific gdbarch when dumping register state to core files
When we have a core file generated by gdb (via the gcore command), gdb dumps
the target description to a note.  During loading of that core file, gdb will
first try to load that saved target description.

This works fine for almost all architectures. But AArch64 has a few
dynamically-generated target descriptions/gdbarch depending on the vector
length that was in use at the time the core file was generated.

The target description gdb dumps to the core file note is the one generated
at the time of attachment/startup.  If, for example, the SVE vector length
changed during execution, this would not reflect on the core file, as gdb
would still dump the initial target description.

Another issue is that the gdbarch potentially doesn't match the thread's
real gdbarch, and so things like the register cache may have different formats
and sizes.

To address this, fetch the thread's architecture before dumping its register
state.  That way we will always use the correct target description/gdbarch.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2023-10-04 16:23:40 +01:00
Luis Machado
147fa85a60 Get rid of linux-core-thread-data
This struct type seems to have been used in the past as a callback
parameter.  Now it seems that case is no longer true, so we can simplify
things by passing the individual parameters linux_core_thread_data
encapsulates directly to the functions.

This is just a cleanup before the next change.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-10-04 16:23:40 +01:00
Andrew Burgess
c14993e9dc gdb/corefile: write NT_GDB_TDESC based on signalled thread
When creating a core file from within GDB we include a NT_GDB_TDESC
that includes the target description of the architecture in use.

For architectures with dynamic architectures (e.g. AArch64 with
sve/sme) the original architecture, calculated from the original
target description, might not match the per-thread architecture.

In the general case, where each thread has a different architecture,
then we really need a separate NT_GDB_TDESC for each thread, however,
there's currently no way to read in multiple NT_GDB_TDESC.

This commit is a step towards per-thread NT_GDB_TDESC.  In this commit
I have updated the function that writes the NT_GDB_TDESC to accept a
gdbarch (rather than calling target_gdbarch() to find a gdbarch), and
I now pass in the gdbarch of the signalled thread.

In many cases (though NOT all) targets with dynamic architectures
really only use a single architecture, even when there are multiple
threads, so in the common case, this should ensure that GDB emits an
architecture that is more likely to be correct.

Additional work will be needed in order to support corefiles with
truly per-thread architectures, but that will need to be done in the
future.
2023-10-03 17:43:50 +01:00
Tom Tromey
ef0f16ccf8 Remove explanatory comments from includes
I noticed a comment by an include and remembered that I think these
don't really provide much value -- sometimes they are just editorial,
and sometimes they are obsolete.  I think it's better to just remove
them.  Tested by rebuilding.

Approved-By: Andrew Burgess <aburgess@redhat.com>
2023-09-20 11:45:16 -06:00
Simon Marchi
4a1283c8d5 gdb: pass execing and following inferior to inferior_execd observers
The upcoming patch to support exec in the amd-dbgapi target needs to
detach amd-dbgapi from the inferior doing the exec and attach amd-dbgapi
to the inferior continuing the execution.  They may or may not be the
same, depending on the `set follow-exec-mode` setting.  But even if they
are the same, we need to do the detach / attach dance.

With the current observable signature, the observers only receive the
inferior in which execution continues (the "following" inferior).

Change the signature to pass both inferiors, and update all existing
observers.

Change-Id: I259d1ea09f70f43be739378d6023796f2fce2659
Reviewed-By: Pedro Alves <pedro@palves.net>
2023-04-17 13:47:13 -04:00
Pedro Alves
58c010877e displaced step: pass down target_waitstatus instead of gdb_signal
This commit tweaks displaced_step_finish & friends to pass down a
target_waitstatus instead of a gdb_signal.  This is needed because a
patch later in the step-over-{thread-exit,clone] series will want to
make displaced_step_buffers::finish handle
TARGET_WAITKIND_THREAD_EXITED.  It also helps with the
TARGET_WAITKIND_THREAD_CLONED patch later in that same series.

It's also a bit more logical this way, as we don't have to pass down
signals when the thread didn't actually stop for a signal.  So we can
also think of it as a clean up.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=27338
Change-Id: I4c5d338647b028071bc498c4e47063795a2db4c0
Approved-By: Andrew Burgess <aburgess@redhat.com>
2023-03-27 17:17:20 +01:00
Tom Tromey
2d39ccd3d1 Unify arch_integer_type and init_integer_type
This unifies arch_integer_type and init_integer_type by using a type
allocator.

Reviewed-By: Simon Marchi <simon.marchi@efficios.com>
2023-03-18 11:12:37 -06:00
Tom Tromey
cc495054ad Remove arch_type
This removes arch_type, replacing all uses with the new type
allocator.

Reviewed-By: Simon Marchi <simon.marchi@efficios.com>
2023-03-18 11:12:37 -06:00
Andrew Burgess
deb65a3cd8 gdb: add gdbarch::displaced_step_buffer_length
The gdbarch::max_insn_length field is used mostly to support displaced
stepping; it controls the size of the buffers allocated for the
displaced-step instruction, and is also used when first copying the
instruction, and later, when fixing up the instruction, in order to
read in and parse the instruction being stepped.

However, it has started to be used in other places in GDB, for
example, it's used in the Python disassembler API, and it is used on
amd64 as part of branch-tracing instruction classification.

The problem is that the value assigned to max_insn_length is not
always the maximum instruction length, but sometimes is a multiple of
that length, as required to support displaced stepping, see rs600,
ARM, and AArch64 for examples of this.

It seems to me that we are overloading the meaning of the
max_insn_length field, and I think that could potentially lead to
confusion.

I propose that we add a new gdbarch field,
gdbarch::displaced_step_buffer_length, this new field will do
exactly what it says on the tin; represent the required displaced step
buffer size.  The max_insn_length field can then do exactly what it
claims to do; represent the maximum length of a single instruction.

As some architectures (e.g. i386, and amd64) only require their
displaced step buffers to be a single instruction in size, I propose
that the default for displaced_step_buffer_length will be the
value of max_insn_length.  Architectures than need more buffer space
can then override this default as needed.

I've updated all architectures to setup the new field if appropriate,
and I've audited all calls to gdbarch_max_insn_length and switched to
gdbarch_displaced_step_buffer_length where appropriate.

There should be no user visible changes after this commit.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-03-13 21:51:04 +00:00
Joel Brobecker
213516ef31 Update copyright year range in header of all files managed by GDB
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
2023-01-01 17:01:16 +04:00
Luis Machado
8181f0045d Document the memory_tagged argument for memory region callbacks
There were no comments in some instances (gdb/defs.h, gdb/core.c and
gdb/linux-tdep.c), so address that by adding comments where those are missing.
2022-11-23 09:45:48 +00:00
Markus Metzger
8d56636a0e gdb, gdbserver: support dlmopen()
In glibc, the r_debug structure contains (amongst others) the following
fields:

  int r_version:
    Version number for this protocol.  It should be greater than 0.

If r_version is 2, struct r_debug is extended to struct r_debug_extended
with one additional field:

  struct r_debug_extended *r_next;
    Link to the next r_debug_extended structure.  Each r_debug_extended
    structure represents a different namespace.  The first r_debug_extended
    structure is for the default namespace.

1. Change solib_svr4_r_map argument to take the debug base.
2. Add solib_svr4_r_next to find the link map in the next namespace from
the r_next field.
3. Update svr4_current_sos_direct to get the link map in the next namespace
from the r_next field.
4. Don't check shared libraries in other namespaces when updating shared
libraries in a new namespace.
5. Update svr4_same to check the load offset in addition to the name
6. Update svr4_default_sos to also set l_addr_inferior
7. Change the flat solib_list into a per-namespace list using the
namespace's r_debug address to identify the namespace.

Add gdb.base/dlmopen.exp to test this.

To remain backwards compatible with older gdbserver, we reserve the
namespace zero for a flat list of solibs from all namespaces.  Subsequent
patches will extend RSP to allow listing libraries grouped by namespace.

This fixes PR 11839.

Co-authored-by: Lu, Hongjiu  <hongjiu.lu@intel.com>
2022-10-18 14:16:08 +02:00
Simon Marchi
82d23ca811 gdb: fix auxv caching
There's a flaw in the interaction of the auxv caching and the fact that
target_auxv_search allows reading auxv from an arbitrary target_ops
(passed in as a parameter).  This has consequences as explained in this
thread:

  https://inbox.sourceware.org/gdb-patches/20220719144542.1478037-1-luis.machado@arm.com/

In summary, when loading an AArch64 core file with MTE support by
passing the executable and core file names directly to GDB, we see the
MTE info:

    $ ./gdb -nx --data-directory=data-directory -q aarch64-mte-gcore aarch64-mte-gcore.core
    ...
    Program terminated with signal SIGSEGV, Segmentation fault
    Memory tag violation while accessing address 0x0000ffff8ef5e000
    Allocation tag 0x1
    Logical tag 0x0.
    #0  0x0000aaaade3d0b4c in ?? ()
    (gdb)

But if we do it as two separate commands (file and core) we don't:

    $ ./gdb -nx --data-directory=data-directory -q -ex "file aarch64-mte-gcore" -ex "core aarch64-mte-gcore.core"
    ...
    Program terminated with signal SIGSEGV, Segmentation fault.
    #0  0x0000aaaade3d0b4c in ?? ()
    (gdb)

The problem with the latter is that auxv data gets improperly cached
between the two commands.  When executing the file command, auxv gets
first queried here, when loading the executable:

    #0  target_auxv_search (ops=0x55555b842400 <exec_ops>, match=0x9, valp=0x7fffffffc5d0) at /home/simark/src/binutils-gdb/gdb/auxv.c:383
    #1  0x0000555557e576f2 in svr4_exec_displacement (displacementp=0x7fffffffc8c0) at /home/simark/src/binutils-gdb/gdb/solib-svr4.c:2482
    #2  0x0000555557e594d1 in svr4_relocate_main_executable () at /home/simark/src/binutils-gdb/gdb/solib-svr4.c:2878
    #3  0x0000555557e5989e in svr4_solib_create_inferior_hook (from_tty=1) at /home/simark/src/binutils-gdb/gdb/solib-svr4.c:2933
    #4  0x0000555557e6e49f in solib_create_inferior_hook (from_tty=1) at /home/simark/src/binutils-gdb/gdb/solib.c:1253
    #5  0x0000555557f33e29 in symbol_file_command (args=0x7fffffffe01c "aarch64-mte-gcore", from_tty=1) at /home/simark/src/binutils-gdb/gdb/symfile.c:1655
    #6  0x00005555573319c3 in file_command (arg=0x7fffffffe01c "aarch64-mte-gcore", from_tty=1) at /home/simark/src/binutils-gdb/gdb/exec.c:555
    #7  0x0000555556e47185 in do_simple_func (args=0x7fffffffe01c "aarch64-mte-gcore", from_tty=1, c=0x612000047740) at /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:95
    #8  0x0000555556e551c9 in cmd_func (cmd=0x612000047740, args=0x7fffffffe01c "aarch64-mte-gcore", from_tty=1) at /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:2543
    #9  0x00005555580e63fd in execute_command (p=0x7fffffffe02c "e", from_tty=1) at /home/simark/src/binutils-gdb/gdb/top.c:692
    #10 0x0000555557771913 in catch_command_errors (command=0x5555580e55ad <execute_command(char const*, int)>, arg=0x7fffffffe017 "file aarch64-mte-gcore", from_tty=1, do_bp_actions=true) at /home/simark/src/binutils-gdb/gdb/main.c:513
    #11 0x0000555557771fba in execute_cmdargs (cmdarg_vec=0x7fffffffd570, file_type=CMDARG_FILE, cmd_type=CMDARG_COMMAND, ret=0x7fffffffd230) at /home/simark/src/binutils-gdb/gdb/main.c:608
    #12 0x00005555577755ac in captured_main_1 (context=0x7fffffffda10) at /home/simark/src/binutils-gdb/gdb/main.c:1299
    #13 0x0000555557775c2d in captured_main (data=0x7fffffffda10) at /home/simark/src/binutils-gdb/gdb/main.c:1320
    #14 0x0000555557775cc2 in gdb_main (args=0x7fffffffda10) at /home/simark/src/binutils-gdb/gdb/main.c:1345
    #15 0x00005555568bdcbe in main (argc=10, argv=0x7fffffffdba8) at /home/simark/src/binutils-gdb/gdb/gdb.c:32

Here, target_auxv_search is called on the inferior's target stack.  The
target stack only contains the exec target, so the query returns empty
auxv data.  This gets cached for that inferior in `auxv_inferior_data`.

In its constructor (before it is pushed to the inferior's target stack),
the core_target needs to identify the right target description from the
core, and for that asks the gdbarch to read a target description from
the core file.  Because some implementations of
gdbarch_core_read_description (such as AArch64's) need to read auxv data
from the core in order to determine the right target description, the
core_target passes a pointer to itself, allowing implementations to call
target_auxv_search it.  However, because we have previously cached
(empty) auxv data for that inferior, target_auxv_search searched that
cached (empty) auxv data, not auxv data read from the core.  Remember
that this data was obtained by reading auxv on the inferior's target
stack, which only contained an exec target.

The problem I see is that while target_auxv_search offers the
flexibility of reading from an arbitrary (passed as an argument) target,
the caching doesn't do the distinction of which target is being queried,
and where the cached data came from.  So, you could read auxv from a
target A, it gets cached, then you try to read auxv from a target B, and
it returns the cached data from target A.  That sounds wrong.  In our
case, we expect to read different auxv data from the core target than
what we have read from the target stack earlier, so it doesn't make
sense to hit the cache in this case.

To fix this, I propose splitting the code paths that read auxv data from
an inferior's target stack and those that read from a passed-in target.
The code path that reads from the target stack will keep caching,
whereas the one that reads from a passed-in target won't.  And since,
searching in auxv data is independent from where this data came from,
split the "read" part from the "search" part.

From what I understand, auxv caching was introduced mostly to reduce
latency on remote connections, when doing many queries.  With the change
I propose, only the queries done while constructing the core_target
end up not using cached auxv data.  This is fine, because there are just
a handful of queries max, done at this point, and reading core files is
local.

The changes to auxv functions are:

 - Introduce 2 target_read_auxv functions.  One reads from an explicit
   target_ops and doesn't do caching (to be used in
   gdbarch_core_read_description context).  The other takes no argument,
   reads from the current inferior's target stack (it looks just like a
   standard target function wrapper) and does caching.

   The first target_read_auxv actually replaces get_auxv_inferior_data,
   since it became a trivial wrapper around it.

 - Change the existing target_auxv_search to not read auxv data from the
   target, but to accept it as a parameter (a gdb::byte_vector).  This
   function doesn't care where the data came from, it just searches in
   it.  It still needs to take a target_ops and gdbarch to know how to
   parse auxv entries.

 - Add a convenience target_auxv_search overload that reads auxv
   data from the inferior's target stack and searches in it.  This
   overload is useful to replace the exist target_auxv_search calls that
   passed the `current_inferior ()->top_target ()` target and keep the
   call sites short.

 - Modify parse_auxv to accept a target_ops and gdbarch to use for
   parsing entries.  Not strictly related to the rest of this change,
   but it seems like a good change in the context.

Changes in architecture-specific files (tdep and nat):

 - In linux-tdep, linux_get_hwcap and linux_get_hwcap2 get split in two,
   similar to target_auxv_search.  One version receives auxv data,
   target and arch as parameters.  The other gets everything from the
   current inferior.  The latter is for convenience, to avoid making
   call sites too ugly.

 - Call sites of linux_get_hwcap and linux_get_hwcap2 are adjusted to
   use either of the new versions.  The call sites in
   gdbarch_core_read_description context explicitly read auxv data from
   the passed-in target and call the linux_get_hwcap{,2} function with
   parameters.  Other call sites use the versions without parameters.

 - Same idea for arm_fbsd_read_description_auxv.

 - Call sites of target_auxv_search that passed
   `current_inferior ()->top_target ()` are changed to use the
   target_auxv_search overload that works in the current inferior.

Reviewed-By: John Baldwin <jhb@FreeBSD.org>
Reviewed-By: Luis Machado <luis.machado@arm.com>
Change-Id: Ib775a220cf1e76443fb7da2fdff8fc631128fe66
2022-10-11 13:52:18 -04:00
Simon Marchi
b872057a63 gdbsupport: convert FILEIO_* macros to an enum
Converting from free-form macros to an enum gives a bit of type-safety.
This caught places where we would assign host error numbers to what
should contain a target fileio error number, for instance in
target_fileio_pread.

I added the FILEIO_SUCCESS enumerator, because
remote.c:remote_hostio_parse_result initializes the remote_errno output
variable to 0.  It seems better to have an explicit enumerator than to
assign a value for which there is no enumerator.  I considered
initializing this variable to FILEIO_EUNKNOWN instead, such that if the
remote side replies with an error and omits the errno value, we'll get
an errno that represents an error instead of 0 (which reprensents no
error).  But it's not clear what the consequences of that change would
be, so I prefer to err on the side of caution and just keep the existing
behavior (there is no intended change in behavior with this patch).

Note that remote_hostio_parse_resul still reads blindly what the remote
side sends as a target errno into this variable, so we can still end up
with a nonsensical value here.  It's not good, but out of the scope of
this patch.

Convert host_to_fileio_error and fileio_errno_to_host to return / accept
a fileio_error instead of an int, and cascade the change in the whole
chain that uses that.

Change-Id: I454b0e3fcf0732447bc872252fa8e57d138b0e03
2022-09-21 14:11:03 -04:00
Simon Marchi
df86565b31 gdb: remove TYPE_LENGTH
Remove the macro, replace all uses with calls to type::length.

Change-Id: Ib9bdc954576860b21190886534c99103d6a47afb
2022-09-21 11:05:21 -04:00
Simon Marchi
8a50fdcefc gdb: add type::target_type / type::set_target_type
Add the `target_type` and `set_target_type` methods on `struct type`, in order
to remove the `TYPE_TARGET_TYPE` macro.  In this patch, the macro is changed to
use the getter, so all the call sites of the macro that are used as a setter
are changed to use the setter method directly.  The next patch will remove the
macro completely.

Change-Id: I85ce24d847763badd34fdee3e14b8c8c14cb3161
2022-09-21 10:53:55 -04:00
Tom Tromey
cb275538db Use registry in gdbarch
gdbarch implements its own registry-like approach.  This patch changes
it to instead use registry.h.  It's a rather large patch but largely
uninteresting -- it's mostly a straightforward conversion from the old
approach to the new one.

The main benefit of this change is that it introduces type safety to
the gdbarch registry.  It also removes a bunch of code.

One possible drawback is that, previously, the gdbarch registry
differentiated between pre- and post-initialization setup.  This
doesn't seem very important to me, though.
2022-08-04 13:28:04 -06:00
Tom Tromey
08b8a139c9 Rewrite registry.h
This rewrites registry.h, removing all the macros and replacing it
with relatively ordinary template classes.  The result is less code
than the previous setup.  It replaces large macros with a relatively
straightforward C++ class, and now manages its own cleanup.

The existing type-safe "key" class is replaced with the equivalent
template class.  This approach ended up requiring relatively few
changes to the users of the registry code in gdb -- code using the key
system just required a small change to the key's declaration.

All existing users of the old C-like API are now converted to use the
type-safe API.  This mostly involved changing explicit deletion
functions to be an operator() in a deleter class.

The old "save/free" two-phase process is removed, and replaced with a
single "free" phase.  No existing code used both phases.

The old "free" callbacks took a parameter for the enclosing container
object.  However, this wasn't truly needed and is removed here as
well.
2022-07-28 14:16:50 -06:00
Luis Machado
68cffbbd44 [AArch64] MTE corefile support
Teach GDB how to dump memory tags for AArch64 when using the gcore command
and how to read memory tag data back from a core file generated by GDB
(via gcore) or by the Linux kernel.

The format is documented in the Linux Kernel documentation [1].

Each tagged memory range (listed in /proc/<pid>/smaps) gets dumped to its
own PT_AARCH64_MEMTAG_MTE segment. A section named ".memtag" is created for each
of those segments when reading the core file back.

To save a little bit of space, given MTE tags only take 4 bits, the memory tags
are stored packed as 2 tags per byte.

When reading the data back, the tags are unpacked.

I've added a new testcase to exercise the feature.

Build-tested with --enable-targets=all and regression tested on aarch64-linux
Ubuntu 20.04.

[1] Documentation/arm64/memory-tagging-extension.rst (Core Dump Support)
2022-07-19 15:24:31 +01:00
Tom Tromey
6cb06a8cda Unify gdb printf functions
Now that filtered and unfiltered output can be treated identically, we
can unify the printf family of functions.  This is done under the name
"gdb_printf".  Most of this patch was written by script.
2022-03-29 12:46:24 -06:00
Tom Tromey
0426ad513f Unify gdb puts functions
Now that filtered and unfiltered output can be treated identically, we
can unify the puts family of functions.  This is done under the name
"gdb_puts".  Most of this patch was written by script.
2022-03-29 12:46:24 -06:00
Aaron Merey
39f53acb41 gdb: Add soname to build-id mapping for core files
Since commit aa2d5a422 gdb has been able to read executable and shared
library build-ids within core files.

Expand this functionality so that each core file bfd maintains a map of
soname to build-id for each shared library referenced in the core file.

This feature may be used to verify that gdb has found the correct shared
libraries for core files and to facilitate downloading shared libaries via
debuginfod.
2022-03-21 14:11:51 -04:00
Simon Marchi
0b313e95a7 gdb/linux-tdep: move "Perms" column right
Commit 29ef4c0699 ("gdb/linux-tdep.c: Add Perms to the 'info proc
mappings' output") has broken test gdb.base/info-proc.exp on Linux,
because it changes the output of "info proc mappings" in a way that the
test does not expect (my bad for not testing before pushing).

I looked at how FreeBSD handles this, since I remembered it did show
permission flags.  It looks like this:

          Start Addr           End Addr       Size     Offset   Flags   File
            0x200000           0x243000    0x43000        0x0  r-- CN-- /usr/local/bin/tmux

(I think that `Flags` and the flags not being aligned is not
intentional)

The test passes on FreeBSD, because the test looks for four hex numbers
in a row and ignores the rest:

    ".*Mapped address spaces:.*${hex}${ws}${hex}${ws}${hex}${ws}${hex}.*"

I suggest fixing it on Linux by moving the flags column to the same
place as in the FreeBSD output.  It makes things a bit more consistent
between OSes, and we don't have to touch the test.

At the same time, make use of the actual length of the permission's
string to specify the number of characters to print.

Before this patch, the output looks like:

          Start Addr           End Addr   Perms       Size     Offset objfile
      0x55dd4b544000     0x55dd4b546000   r--p      0x2000        0x0 /usr/bin/sleep

and after, it looks like:

          Start Addr           End Addr       Size     Offset  Perms  objfile
      0x5622ae662000     0x5622ae664000     0x2000        0x0  r--p   /usr/bin/sleep

Change-Id: If0fc167b010b25f97a3c54e2f491df4973ccde8f
2022-02-24 07:29:08 -05:00
Simon Marchi
1165955276 gdb/linux-tdep: make read_mapping return a structure
Change read_mapping to return a structure instead of taking many output
parameters.  Change the string + length output parameters (permissions
and device) to be gdb::string_view, since that's what string_view is
for (a non-NULL terminated view on a string).  No changes in behavior
expected.

Change-Id: I86e627d84d3dda8c9b835592b0f4de8d90d12112
2022-02-24 07:29:05 -05:00
Dominik 'Disconnect3d' Czarnota
29ef4c0699 gdb/linux-tdep.c: Add Perms to the 'info proc mappings' output
Fixes #28914 and so it adds a 'Perms' (permissions) column to the
'info proc mappings' command output. This will allow users to know
the memory pages permissions right away from GDB instead of having
to fetch them from the /proc/$pid/maps file (which is also what GDB
does internally, but it just did not print that column).

Below I am also showing how an example output looks like before and
after this commit in case someone wonders.

On i386 targets - before this commit:
```
(gdb) info proc mappings
process 3461464
Mapped address spaces:

    Start Addr   End Addr        Size     Offset objfile
    0x56555000 0x56556000      0x1000        0x0 /home/dc/src/binutils-gdb/build/a.out
    0x56556000 0x56557000      0x1000     0x1000 /home/dc/src/binutils-gdb/build/a.out
    0x56557000 0x56558000      0x1000     0x2000 /home/dc/src/binutils-gdb/build/a.out
    0x56558000 0x5655a000      0x2000     0x2000 /home/dc/src/binutils-gdb/build/a.out
    0xf7fc4000 0xf7fc8000      0x4000        0x0 [vvar]
    0xf7fc8000 0xf7fca000      0x2000        0x0 [vdso]
    0xf7fca000 0xf7fcb000      0x1000        0x0 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7fcb000 0xf7fee000     0x23000     0x1000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7fee000 0xf7ffb000      0xd000    0x24000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7ffb000 0xf7ffe000      0x3000    0x30000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xfffdc000 0xffffe000     0x22000        0x0 [stack]
(gdb)
```

On i386 targets - after this commit:
```
(gdb) info proc mappings
process 3461464
Mapped address spaces:

    Start Addr   End Addr   Perms       Size     Offset objfile
    0x56555000 0x56556000   r--p      0x1000        0x0 /home/dc/src/binutils-gdb/build/a.out
    0x56556000 0x56557000   r-xp      0x1000     0x1000 /home/dc/src/binutils-gdb/build/a.out
    0x56557000 0x56558000   r--p      0x1000     0x2000 /home/dc/src/binutils-gdb/build/a.out
    0x56558000 0x5655a000   rw-p      0x2000     0x2000 /home/dc/src/binutils-gdb/build/a.out
    0xf7fc4000 0xf7fc8000   r--p      0x4000        0x0 [vvar]
    0xf7fc8000 0xf7fca000   r-xp      0x2000        0x0 [vdso]
    0xf7fca000 0xf7fcb000   r--p      0x1000        0x0 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7fcb000 0xf7fee000   r-xp     0x23000     0x1000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7fee000 0xf7ffb000   r--p      0xd000    0x24000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xf7ffb000 0xf7ffe000   rw-p      0x3000    0x30000 /usr/lib/i386-linux-gnu/ld-2.33.so
    0xfffdc000 0xffffe000   rw-p     0x22000        0x0 [stack]
(gdb)
```

On amd64 targets - after this commit:
```
(gdb) info proc mappings
process 3461869
Mapped address spaces:

          Start Addr           End Addr   Perms       Size     Offset objfile
      0x555555554000     0x555555555000   r--p      0x1000        0x0 /home/dc/src/binutils-gdb/build/a.out
      0x555555555000     0x555555556000   r-xp      0x1000     0x1000 /home/dc/src/binutils-gdb/build/a.out
      0x555555556000     0x555555557000   r--p      0x1000     0x2000 /home/dc/src/binutils-gdb/build/a.out
      0x555555557000     0x555555559000   rw-p      0x2000     0x2000 /home/dc/src/binutils-gdb/build/a.out
      0x7ffff7fc3000     0x7ffff7fc7000   r--p      0x4000        0x0 [vvar]
      0x7ffff7fc7000     0x7ffff7fc9000   r-xp      0x2000        0x0 [vdso]
      0x7ffff7fc9000     0x7ffff7fca000   r--p      0x1000        0x0 /usr/lib/x86_64-linux-gnu/ld-2.33.so
      0x7ffff7fca000     0x7ffff7ff1000   r-xp     0x27000     0x1000 /usr/lib/x86_64-linux-gnu/ld-2.33.so
      0x7ffff7ff1000     0x7ffff7ffb000   r--p      0xa000    0x28000 /usr/lib/x86_64-linux-gnu/ld-2.33.so
      0x7ffff7ffb000     0x7ffff7fff000   rw-p      0x4000    0x31000 /usr/lib/x86_64-linux-gnu/ld-2.33.so
      0x7ffffffdd000     0x7ffffffff000   rw-p     0x22000        0x0 [stack]
  0xffffffffff600000 0xffffffffff601000   --xp      0x1000        0x0 [vsyscall]
(gdb)
```

Signed-off-by: Dominik 'Disconnect3d' Czarnota <dominik.b.czarnota@gmail.com>
Change-Id: I4991f6cc758cd532eae3ae98c29d22e7bd9d9c36
2022-02-23 09:10:43 -05:00
Tom Tromey
d322d6d69d Move gdb_regex to gdbsupport
This moves the gdb_regex convenience class to gdbsupport.
2022-01-18 10:14:43 -07:00
Tom Tromey
bf31fd38f0 Move gdb obstack code to gdbsupport
This moves the gdb-specific obstack code -- both extensions like
obconcat and obstack_strdup, and things like auto_obstack -- to
gdbsupport.
2022-01-18 10:14:42 -07:00
Hannes Domani
24fe764c8a Add _sigsys info to siginfo struct
This patch adds information about _sigsys structure from newer
kernels, so that $_siginfo decoding can show information about
_sigsys, making it easier for developers to debug seccomp failures.
Requested in PR gdb/24283.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=24283
2022-01-08 14:17:49 +01:00
Joel Brobecker
4a94e36819 Automatic Copyright Year update after running gdb/copyright.py
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.

For the avoidance of doubt, all changes in this commits were
performed by the script.
2022-01-01 19:13:23 +04:00
Aaron Merey
aa95b2d438 gdb: Add aliases for read_core_file_mappings callbacks
Add aliases read_core_file_mappings_loop_ftype and
read_core_file_mappings_pre_loop_ftype.  Intended for use with
read_core_file_mappings.

Also add build_id parameter to read_core_file_mappings_loop_ftype.
2021-11-16 22:29:51 -05:00
H.J. Lu
c0154a4a21 gdb: Don't assume r_ldsomap when r_version > 1 on Linux
The r_ldsomap field is specific to Solaris (part of librtld_db), and
should never be accessed for Linux.  glibc is planning to add a field
to support multiple namespaces.  But there will be no r_ldsomap when
r_version is bumped to 2.  Add linux_[ilp32|lp64]_fetch_link_map_offsets
to set r_ldsomap_offset to -1 and use them for Linux targets.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28236
2021-08-17 07:05:57 -07:00
Simon Marchi
fd2dec2a45 gdb: make inferior::m_args an std::string
With the current code, both a NULL pointer and an empty string can mean
"no arguments".  We don't need this distinction.  Changing to a string
has the advantage that there is now a single state for that (an empty
string), which makes the code a bit simpler in my opinion.

Change-Id: Icdc622820f7869478791dbaa84b4a1c7fec21ced
2021-07-23 15:38:54 -04:00
Simon Marchi
e51695253e gdb: add setter/getter for inferior arguments
Add args/set_args to the inferior class, remove the set_inferior_args
and get_inferior_args functions, that would just be wrappers around
them.

Change-Id: If87d52f3402ce08be26c32897ae8915d9f6d1ea3
2021-07-23 15:38:54 -04:00
Simon Marchi
1edb66d856 gdb: make thread_info::suspend private, add getters / setters
A following patch will want to take some action when a pending wait
status is set on or removed from a thread.  Add a getter and a setter on
thread_info for the pending waitstatus, so that we can add some code in
the setter later.

The thing is, the pending wait status field is in the
thread_suspend_state, along with other fields that we need to backup
before and restore after the thread does an inferior function call.
Therefore, make the thread_suspend_state member private
(thread_info::suspend becomes thread_info::m_suspend), and add getters /
setters for all of its fields:

 - pending wait status
 - stop signal
 - stop reason
 - stop pc

For the pending wait status, add the additional has_pending_waitstatus
and clear_pending_waitstatus methods.

I think this makes the thread_info interface a bit nicer, because we
now access the fields as:

  thread->stop_pc ()

rather than

  thread->suspend.stop_pc

The stop_pc field being in the `suspend` structure is an implementation
detail of thread_info that callers don't need to be aware of.

For the backup / restore of the thread_suspend_state structure, add
save_suspend_to and restore_suspend_from methods.  You might wonder why
`save_suspend_to`, as opposed to a simple getter like

  thread_suspend_state &suspend ();

I want to make it clear that this is to be used only for backing up and
restoring the suspend state, _not_ to access fields like:

  thread->suspend ()->stop_pc

Adding some getters / setters allows adding some assertions.  I find
that this helps understand how things are supposed to work.  Add:

 - When getting the pending status (pending_waitstatus method), ensure
   that there is a pending status.
 - When setting a pending status (set_pending_waitstatus method), ensure
   there is no pending status.

There is one case I found where this wasn't true - in
remote_target::process_initial_stop_replies - which needed adjustments
to respect that contract.  I think it's because
process_initial_stop_replies is kind of (ab)using the
thread_info::suspend::waitstatus to store some statuses temporarily, for
its internal use (statuses it doesn't intent on leaving pending).

process_initial_stop_replies pulls out stop replies received during the
initial connection using target_wait.  It always stores the received
event in `evthread->suspend.waitstatus`.  But it only sets
waitstatus_pending_p, if it deems the event interesting enough to leave
pending, to be reported to the core:

      if (ws.kind != TARGET_WAITKIND_STOPPED
	  || ws.value.sig != GDB_SIGNAL_0)
	evthread->suspend.waitstatus_pending_p = 1;

It later uses this flag a bit below, to choose which thread to make the
"selected" one:

      if (selected == NULL
	  && thread->suspend.waitstatus_pending_p)
	selected = thread;

And ultimately that's used if the user-visible mode is all-stop, so that
we print the stop for that interesting thread:

  /* In all-stop, we only print the status of one thread, and leave
     others with their status pending.  */
  if (!non_stop)
    {
      thread_info *thread = selected;
      if (thread == NULL)
	thread = lowest_stopped;
      if (thread == NULL)
	thread = first;

      print_one_stopped_thread (thread);
    }

But in any case (all-stop or non-stop), print_one_stopped_thread needs
to access the waitstatus value of these threads that don't have a
pending waitstatus (those that had TARGET_WAITKIND_STOPPED +
GDB_SIGNAL_0).  This doesn't work with the assertions I've
put.

So, change the code to only set the thread's wait status if it is an
interesting one that we are going to leave pending.  If the thread
stopped due to a non-interesting event (TARGET_WAITKIND_STOPPED +
GDB_SIGNAL_0), don't store it.  Adjust print_one_stopped_thread to
understand that if a thread has no pending waitstatus, it's because it
stopped with TARGET_WAITKIND_STOPPED + GDB_SIGNAL_0.

The call to set_last_target_status also uses the pending waitstatus.
However, given that the pending waitstatus for the thread may have been
cleared in print_one_stopped_thread (and that there might not even be a
pending waitstatus in the first place, as explained above), it is no
longer possible to do it at this point.  To fix that, move the call to
set_last_target_status in print_one_stopped_thread.  I think this will
preserve the existing behavior, because set_last_target_status is
currently using the current thread's wait status.  And the current
thread is the last one for which print_one_stopped_thread is called.  So
by calling set_last_target_status in print_one_stopped_thread, we'll get
the same result.  set_last_target_status will possibly be called
multiple times, but only the last call will matter.  It just means
possibly more calls to set_last_target_status, but those are cheap.

Change-Id: Iedab9653238eaf8231abcf0baa20145acc8b77a7
2021-07-12 20:46:53 -04:00
Simon Marchi
c90e7d6352 gdbsupport, gdb: give names to observers
Give a name to each observer, this will help produce more meaningful
debug message.

gdbsupport/ChangeLog:

	* observable.h (class observable) <struct observer> <observer>:
	Add name parameter.
	<name>: New field.
	<attach>: Add name parameter, update all callers.

Change-Id: Ie0cc4664925215b8d2b09e026011b7803549fba0
2021-04-24 19:26:41 -04:00
Simon Marchi
328d42d87e gdb: remove current_top_target function
The current_top_target function is a hidden dependency on the current
inferior.  Since I'd like to slowly move towards reducing our dependency
on the global current state, remove this function and make callers use

  current_inferior ()->top_target ()

There is no expected change in behavior, but this one step towards
making those callers use the inferior from their context, rather than
refer to the global current inferior.

gdb/ChangeLog:

	* target.h (current_top_target): Remove, make callers use the
	current inferior instead.
	* target.c (current_top_target): Remove.

Change-Id: Iccd457036f84466cdaa3865aa3f9339a24ea001d
2021-03-24 18:08:24 -04:00
Luis Machado
1e735120b9 Refactor parsing of /proc/<pid>/smaps
The Linux kernel exposes the information about MTE-protected pages via the
proc filesystem, more specifically through the smaps file.

What we're looking for is a mapping with the 'mt' flag, which tells us that
mapping was created with a PROT_MTE flag and, thus, is capable of using memory
tagging.

We already parse that file for other purposes (core file
generation/filtering), so this patch refactors the code to make the parsing
of the smaps file reusable for memory tagging.

The function linux_address_in_memtag_page uses the refactored code to allow
querying for memory tag support in a particular address, and it gets used in the
next patch.

gdb/ChangeLog:

2021-03-24  Luis Machado  <luis.machado@linaro.org>

	* linux-tdep.c (struct smaps_vmflags) <memory_tagging>: New flag
	bit.
	(struct smaps_data): New struct.
	(decode_vmflags): Handle the 'mt' flag.
	(parse_smaps_data): New function, refactored from
	linux_find_memory_regions_full.
	(linux_address_in_memtag_page): New function.
	(linux_find_memory_regions_full): Refactor into parse_smaps_data.
	* linux-tdep.h (linux_address_in_memtag_page): New prototype.
2021-03-24 14:54:50 -03:00
Luis Machado
93e447c605 Convert char array to std::string in linux_find_memory_regions_full
This is a quick cleanup that removes the use of fixed-length char arrays and
uses std::string instead.

gdb/ChangeLog:

2021-03-24  Luis Machado  <luis.machado@linaro.org>

	* linux-tdep.c (linux_find_memory_regions_full): Use std::string
	instead of char arrays.
2021-03-24 14:54:22 -03:00
Andrew Burgess
95ce627aeb gdb: write target description into core file
When a core file is created from within GDB add the target description
into a note within the core file.

When loading a core file, if the target description note is present
then load the target description from the core file.

The benefit of this is that we can be sure that, when analysing the
core file within GDB, that we are using the exact same target
description as was in use at the time the core file was created.

GDB already supports a mechanism for figuring out the target
description from a given corefile; gdbarch_core_read_description.
This new mechanism (GDB adding the target description) is not going to
replace the old mechanism.  Core files generated outside of GDB will
not include a target description, and so GDB still needs to be able to
figure out a target description for these files.

My primary motivation for adding this feature is that, in a future
commit, I will be adding support for bare metal core dumps on some
targets.  For RISC-V specifically, I want to be able to dump all the
available control status registers.  As different targets will present
different sets of register in their target description, including
registers that are possibly not otherwise known to GDB I wanted a way
to capture these registers in the core dump.

I therefore need a mechanism to write out an arbitrary set of
registers, and to then derive a target description from this arbitrary
set when later loading the core file.  The obvious approach (I think)
is to just reuse the target description.

Once I'd decided to add support for writing out the target description
I could either choose to make this RISC-V only, or make it generic.  I
figure that having the target description in the core file doesn't
hurt, and _might_ be helpful.  So that's how I got here, general
support for including the target description in GDB generated core
files.

In previous versions of this patch I added the target description from
generic code (in gcore.c).  However, doing this creates a dependency
between GDB's common code and bfd ELF support.  As ELF support in gdb
is optional (for example the target x86_64-apple-darwin20.3.0 does not
include ELF support) then having gcore.c require ELF support would
break the GDB build in some cases.

Instead, in this version of the patch, writing the target description
note is done from each specific targets make notes function.  Each of
these now calls a common function in gcore-elf.c (which is only linked
in when bfd has ELF support).  And so only targets that are ELF based
will call the new function and we can therefore avoid an unconditional
dependency on ELF support.

gdb/ChangeLog:

	* corelow.c: Add 'xml-tdesc.h' include.
	(core_target::read_description): Load the target description from
	the core file when possible.
	* fbsd-tdep.c (fbsd_make_corefile_notes): Add target description
	note.
	* gcore-elf.c: Add 'gdbsupport/tdesc.h' include.
	(gcore_elf_make_tdesc_note): New function.
	* gcore-elf.h (gcore_elf_make_tdesc_note): Declare.
	* linux-tdep.c (linux_make_corefile_notes): Add target description
	note.
2021-03-05 17:21:41 +00:00