A recent change in glibc 2.42.9000 [1] changes the return type of
strstr() and other string functions to be 'const char *' when the
input is a 'const char *'. This breaks the build in :
../gdbstub/user.c:322:21: error: assignment discards ‘const’ qualifier from pointer target type [-Werror=discarded-qualifiers]
322 | pid_placeholder = strstr(path, "%d");
| ^
Fix this by changing the type of the variables that store the result
of these functions to 'const char *'.
[1] https://sourceware.org/git/?p=glibc.git;a=commit;h=cd748a63ab1a7ae846175c532a3daab341c62690
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/qemu-devel/20251215101937.281722-5-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
A recent change in glibc 2.42.9000 [1] changes the return type of
strstr() and other string functions to be 'const char *' when the
input is a 'const char *'.
This breaks the build in various files with errors such as :
error: initialization discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
208 | char *pidstr = strstr(filename, "%");
| ^~~~~~
Fix this by changing the type of the variables that store the result
of these functions to 'const char *'.
[1] https://sourceware.org/git/?p=glibc.git;a=commit;h=cd748a63ab1a7ae846175c532a3daab341c62690
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20251209174328.698774-1-clg@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The format string for %s has two format characters. This causes it to
emit strings like "466f5bd8/6x" instead of "466f5bd8/6". GDB detects
this and returns EIO, causing all open File I/O calls to fail.
Fixes: 0820a075af ("gdbstub: Adjust gdb_do_syscall to only use uint32_t and uint64_t")
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20251027110344.2289945-35-alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
The actual backend is "Chardev", CharBackend is the frontend side of
it (whatever talks to the backend), let's rename it for readability.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Link: https://lore.kernel.org/r/20251022074612.1258413-1-marcandre.lureau@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This hasn't been needed since d828b92b8a
("accel/tcg: Introduce CF_BP_PAGE").
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This patch increases the value of the MAX_PACKET_LEGNTH to
131104 from 4096 to allow the GDBState.line_buf to be large enough
to accommodate the full contents of the SME ZA storage when the
vector length is maximal. This is in preparation for a related
patch that allows SME register visibility through remote GDB
debugging.
Signed-off-by: Vacha Bhavsar <vacha.bhavsar@oss.qualcomm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20250909161012.2561593-2-vacha.bhavsar@oss.qualcomm.com
[PMM: fixed up comment formatting]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Only accelerator implementations (and the common accelator
code) need to know about AccelClass internals. Move the
definition out but forward declare AccelState and AccelClass.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250703173248.44995-39-philmd@linaro.org>
Unfortunately "system/accel-ops.h" handlers are not only
system-specific. For example, the cpu_reset_hold() hook
is part of the vCPU creation, after it is realized.
Mechanical rename to drop 'system' using:
$ sed -i -e s_system/accel-ops.h_accel/accel-cpu-ops.h_g \
$(git grep -l system/accel-ops.h)
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250703173248.44995-38-philmd@linaro.org>
This patch exposes the gdb_write_register function from
gdbstub/gdbstub.c via the exec/gdbstub.h header file to support use in
plugins to write register contents.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Julian Ganz <neither@nut.email>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
Message-ID: <20250624175351.440780-2-rowanbhart@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250627112512.1880708-6-alex.bennee@linaro.org>
This commit adds support for the `qGDBServerVersion` packet to the qemu
gdbstub which could be used by clients to detect the QEMU version
(and, e.g., use a workaround for known bugs).
This packet is not documented/standarized by GDB but it was implemented
by LLDB gdbstub [0] and is helpful for projects like Pwndbg [1].
This has been implemented by Patryk, who I included in Co-authored-by
and who asked me to send the patch.
[0] https://lldb.llvm.org/resources/lldbgdbremote.html#qgdbserverversion
[1] https://github.com/pwndbg/pwndbg/issues/2648
Co-authored-by: Patryk 'patryk4815' Sondej <patryk.sondej@gmail.com>
Signed-off-by: Dominik 'Disconnect3d' Czarnota <dominik.b.czarnota@gmail.com>
Message-Id: <20250403191340.53343-1-dominik.b.czarnota@gmail.com>
[AJB: fix include, checkpatch linewrap]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250603110204.838117-17-alex.bennee@linaro.org>
When things go wrong we want to assert on the register that failed to
be able to figure out what went wrong.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250603110204.838117-16-alex.bennee@linaro.org>
Currently the CPUClass:gdb_core_xml_file setting is a simple 'const
char *' which the CPU class must set to a fixed string. Allow the
CPU class to instead set a new method gdb_get_core_xml_file() which
returns this string.
This will allow Arm CPUs to use different XML files for AArch32 vs
AArch64 without having to have an extra AArch64-specific class type
purely to give somewhere to set cc->gdb_core_xml_file differently.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250317142819.900029-3-peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Mechanical change using gsed, then style manually adapted
to pass checkpatch.pl script.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250424194905.82506-4-philmd@linaro.org>
Copy to libuser_ss and libsystem_ss.
This file uses semihosting/semihost.h, which has separate
implementations with and without CONFIG_USER_ONLY.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We already have two subdirectories for which we need
to build files twice, for user vs system modes.
Move this handling to the top level.
This cannot be combined with user_ss or system_ss,
because the formulation has not been extended to support
configuration symbols.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
CpuState caches its CPUClass since commit 6fbdff8706
("cpu: cache CPUClass in CPUState for hot code paths"),
use it.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250122093028.52416-9-philmd@linaro.org>
The heavily imported "system/cpus.h" header includes "accel-ops.h"
to get AccelOpsClass type declaration. Reduce headers pressure by
forward declaring it in "qemu/typedefs.h", where we already
declare the AccelCPUState type.
Reduce "system/cpus.h" inclusions by only including
"system/accel-ops.h" when necessary.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250123234415.59850-14-philmd@linaro.org>
Use the tcg_enabled() check so the compiler can elide
the call when TCG isn't available, allowing to remove
the tb_flush() stub.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250123234415.59850-4-philmd@linaro.org>
Allow debugging individual processes in multi-process applications by
starting them with export QEMU_GDB=/tmp/qemu-%d.sock,suspend=n.
Currently one would have to attach to every process to ensure the app
makes progress.
In case suspend=n is not specified, the flow remains unchanged. If it
is specified, then accepting the client connection is delegated to a
thread. In the future this machinery may be reused for handling
reconnections and interruptions.
On accepting a connection, the thread schedules gdb_handlesig() on the
first CPU and wakes it up with host_interrupt_signal. Note that the
result of this gdb_handlesig() invocation is handled, as opposed to
many other existing call sites. These other call sites probably need to
be fixed separately.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20250117001542.8290-7-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-16-alex.bennee@linaro.org>
In case an emulated process execve()s another emulated process, bind()
will fail, because the socket already exists. So try deleting it. Use
the existing unix_listen() function which does this. Link qemu-user
with qemu-sockets.c and add the monitor_get_fd() stub.
Note that it is not possible to handle this in do_execv(): deleting
gdbserver_user_state.socket_path before safe_execve() is not correct,
because the latter may fail, and afterwards we may lose control.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250117001542.8290-3-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-12-alex.bennee@linaro.org>
Just like for QEMU_LOG_FILENAME, replace %d with PID in the GDB socket
path. This allows running multi-process applications with, e.g.,
export QEMU_GDB=/tmp/qemu-%d.sock. Currently this is not possible,
since the first process will cause the subsequent ones to fail due to
not being able to bind() the GDB socket.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20250117001542.8290-2-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-11-alex.bennee@linaro.org>
This commit fixes an incorrect format string for formatting integers
provided to GDB when debugging a target run in QEMU user mode.
The correct format is hexadecimal for both success and errno values,
some of which can be seen here [0].
[0] e65a355022/gdbserver/hostio.cc (L196-L213)
Signed-off-by: Dominik 'Disconnect3d' Czarnota <dominik.b.czarnota@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Fixes: e282010b2e ("gdbstub: Add support for info proc mappings")
Cc: qemu-stable@nongnu.org
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This started as a clean-up to properly pass a Error handler to the
gdbserver_start so we could do the right thing for command line and
HMP invocations.
Now that we have cleaned up foreach_device_config_or_exit() in earlier
patches we can further simplify by it by passing &error_fatal instead
of checking the return value. Having a return value is still useful
for HMP though so tweak the return to use a simple bool instead.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250116160306.1709518-11-alex.bennee@linaro.org>
Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.
Files renamed manually then mechanical change using sed tool.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>
The 'LGPL-2.0+' license identifier has been deprecated since license
list version 2.0rc2 [1] and replaced by the 'LGPL-2.0-or-later' [2]
tag.
[1] https://spdx.org/licenses/LGPL-2.0+.html
[2] https://spdx.org/licenses/LGPL-2.0-or-later.html
Mechanical patch running:
$ sed -i -e s/LGPL-2.0+/LGPL-2.0-or-later/ \
$(git grep -l 'SPDX-License-Identifier: LGPL-2.0+$')
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Add common function to help unregister the GDB register space. This shall be
done in context to the CPU unrealization.
Note: These are common functions exported to arch specific code. For example,
for ARM this code is being referred in associated arch specific patch-set:
Link: https://lore.kernel.org/qemu-devel/20230926103654.34424-1-salil.mehta@huawei.com/
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Tested-by: Xianglai Li <lixianglai@loongson.cn>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Reviewed-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
Tested-by: Zhao Liu <zhao1.liu@intel.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20240716111502.202344-8-salil.mehta@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Coverity reported a memory leak (CID 1549757) in this code and its
admittedly rather clumsy handling of extending the command table.
Instead of handing over a full array of the commands lets use the
lighter weight GPtrArray and simply test for the presence of each
entry as we go. This avoids complications of transferring ownership of
arrays and keeps the final command entries as static entries in the
target code.
Cc: Akihiko Odaki <akihiko.odaki@daynix.com>
Cc: Gustavo Bueno Romero <gustavo.romero@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Gustavo Romero <gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240718094523.1198645-4-alex.bennee@linaro.org>
cmd_startswith is a boolean so use 'true' to set it instead of 1.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Message-Id: <20240628050850.536447-10-gustavo.romero@linaro.org>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-39-alex.bennee@linaro.org>
Allow passing the current CPU context to command handlers via user_ctx
when the handler requires it.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Message-Id: <20240628050850.536447-9-gustavo.romero@linaro.org>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-38-alex.bennee@linaro.org>
Make gdb_hextomem non-internal so it's not confined to use only in
gdbstub.c.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240628050850.536447-8-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-37-alex.bennee@linaro.org>
Currently, it's not possible to have stubs specific to a given target,
even though there are GDB features which are target-specific, like, for
instance, memory tagging.
This commit introduces gdb_extend_qsupported_features,
gdb_extend_query_table, and gdb_extend_set_table functions as interfaces
to extend the qSupported string, the query handler table, and the set
handler table, allowing target-specific stub implementations.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240628050850.536447-4-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-33-alex.bennee@linaro.org>
Move GdbCmdParseEntry and its associated types into a separate header
file to allow the use of GdbCmdParseEntry and other gdbstub command
functions outside of gdbstub.c.
Since GdbCmdParseEntry and get_param are now public, kdoc
GdbCmdParseEntry and rename get_param to gdb_get_cmd_param.
This commit also makes gdb_put_packet public since is used in gdbstub
command handling.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240628050850.536447-3-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-32-alex.bennee@linaro.org>
Change 'process_string_cmd' to return true on success and false on
failure, instead of 0 and -1.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20240628050850.536447-2-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-31-alex.bennee@linaro.org>
The non-standard .fa library suffix breaks the link source
de-duplication done by Meson so drop it.
The lack of link source de-duplication causes AddressSanitizer to
complain ODR violations, and makes GNU ld abort when combined with
clang's LTO.
Fortunately, the non-standard suffix is not necessary anymore for
two reasons.
First, the non-standard suffix was necessary for fork-fuzzing.
Meson wraps all standard-suffixed libraries with --start-group and
--end-group. This made a fork-fuzz.ld linker script wrapped as well and
broke builds. Commit d2e6f9272d ("fuzz: remove fork-fuzzing
scaffolding") dropped fork-fuzzing so we can now restore the standard
suffix.
Second, the libraries are not even built anymore, because it is
possible to just use the object files directly via extract_all_objects().
The occurences of the suffix were detected and removed by performing
a tree-wide search with 'fa' and .fa (note the quotes and dot).
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-ID: <20240524-xkb-v4-4-2de564e5c859@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We used to request declare_dependency() to link_whole static libraries.
If a static library is a thin archive, GNU ld keeps all object files
referenced by the archive open, and sometimes exceeds the open file limit.
Another problem with link_whole is that suboptimal handling of nested
dependencies.
link_whole by itself does not propagate dependencies. In particular,
gnutls, a dependency of crypto, is not propagated to its users, and we
currently workaround the issue by declaring gnutls as a dependency for
each crypto user. On the other hand, if you write something like
libfoo = static_library('foo', 'foo.c', dependencies: gnutls)
foo = declare_dependency(link_whole: libfoo)
libbar = static_library('bar', 'bar.c', dependencies: foo)
bar = declare_dependency(link_whole: libbar, dependencies: foo)
executable('prog', sources: files('prog.c'), dependencies: [foo, bar])
hoping to propagate the gnutls dependency into bar.c, you'll see a
linking failure for "prog", because the foo.c.o object file is included in
libbar.a and therefore it is linked twice into "prog": once from libfoo.a
and once from libbar.a. Here Meson does not see the duplication, it
just asks the linker to link all of libfoo.a and libbar.a into "prog".
Instead of using link_whole, extract objects included in static libraries
and pass them to declare_dependency(); and then the dependencies can be
added as well so that they are propagated, because object files on the
linker command line are always deduplicated.
This requires Meson 1.1.0 or later.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-ID: <20240524-objects-v1-1-07cbbe96166b@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is an experiment to further reduce the amount we throw into the
exec headers. It might not be as useful as I initially thought because
just under half of the users also need gdbserver_start().
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240620152220.2192768-3-alex.bennee@linaro.org>
Get the TaskState pointer calling get_task_state().
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240428221450.26460-11-philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240313213339.82071-4-philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240313213339.82071-3-philmd@linaro.org>
When the terminal GDB_FORK_ENABLED state is reached, the coordination
socket is not needed anymore and is therefore closed. However, if there
is a communication error between QEMU gdbstub and GDB, the generic
error handling code attempts to close it again.
Fix by closing it later - before returning - instead.
Fixes: Coverity CID 1539966
Fixes: d547e711a8 ("gdbstub: Implement follow-fork-mode child")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240312001813.13720-1-iii@linux.ibm.com>
Add stub to handle Xfer:siginfo:read packet query that requests the
machine's siginfo data.
This is used when GDB user executes 'print $_siginfo' and when the
machine stops due to a signal, for instance, on SIGSEGV. The information
in siginfo allows GDB to determiner further details on the signal, like
the fault address/insn when the SIGSEGV is caught.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Message-Id: <20240309030901.1726211-5-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Save target's siginfo into gdbserver_state so it can be used later, for
example, in any stub that requires the target's si_signo and si_code.
This change affects only linux-user mode.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240309030901.1726211-4-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Rename gdb_handlesig_reason back to gdb_handlesig. There is no need to
add a wrapper for gdb_handlesig and rename it when a new parameter is
added.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240309030901.1726211-2-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Currently it's not possible to use gdbstub for debugging linux-user
code that runs in a forked child, which is normally done using the `set
follow-fork-mode child` GDB command. Purely on the protocol level, the
missing piece is the fork-events feature.
However, a deeper problem is supporting $Hg switching between different
processes - right now it can do only threads. Implementing this for the
general case would be quite complicated, but, fortunately, for the
follow-fork-mode case there are a few factors that greatly simplify
things: fork() happens in the exclusive section, there are only two
processes involved, and before one of them is resumed, the second one
is detached.
This makes it possible to implement a simplified scheme: the parent and
the child share the gdbserver socket, it's used only by one of them at
any given time, which is coordinated through a separate socketpair. The
processes can read from the gdbserver socket only one byte at a time,
which is not great for performance, but, fortunately, the
follow-fork-mode handling involves only a few messages.
Advertise the fork-events support, and remember whether GDB has it
as well. Implement the state machine that is initialized on fork(),
decides the current owner of the gdbserver socket, and is terminated
when one of the two processes is detached. The logic for the parent and
the child is the same, only the initial state is different.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240219141628.246823-12-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-13-alex.bennee@linaro.org>
The upcoming follow-fork-mode child support needs to perform certain
actions when GDB detaches from the stopped parent or the stopped child.
Introduce a user-specific hook for this.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240219141628.246823-11-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-12-alex.bennee@linaro.org>
The upcoming follow-fork-mode child support needs to perform certain
actions when GDB switches between the stopped parent and the stopped
child. Introduce a user-specific hook for this.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240219141628.246823-10-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-11-alex.bennee@linaro.org>
The upcoming follow-fork-mode child support requires advertising the
fork-events feature, which is user-specific. Introduce a user-specific
hook for this.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240219141628.246823-9-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-10-alex.bennee@linaro.org>
Paolo Bonzini
Cédric Le Goater
Sean Anderson
Marc-André Lureau
Richard Henderson
Vacha Bhavsar
Philippe Mathieu-Daudé
Rowan Hart
Dominik 'Disconnect3d' Czarnota
Alex Bennée
Pierrick Bouvier
Peter Maydell
Ilya Leoshkevich
Salil Mehta
Gustavo Romero
Akihiko Odaki