Commit Graph

18 Commits

Author SHA1 Message Date
Ilya Leoshkevich
046f143c51 gdbstub: Implement catching syscalls
GDB supports stopping on syscall entry and exit using the "catch
syscall" command. It relies on 3 packets, which are currently not
supported by QEMU:

* qSupported:QCatchSyscalls+ [1]
* QCatchSyscalls: [2]
* T05syscall_entry: and T05syscall_return: [3]

Implement generation and handling of these packets.

[1] https://sourceware.org/gdb/current/onlinedocs/gdb.html/General-Query-Packets.html#qSupported
[2] https://sourceware.org/gdb/current/onlinedocs/gdb.html/General-Query-Packets.html#QCatchSyscalls
[3] https://sourceware.org/gdb/current/onlinedocs/gdb.html/Stop-Reply-Packets.html

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240202152506.279476-5-iii@linux.ibm.com>
[AJB: GString -> g_strdup_printf]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240207163812.3231697-14-alex.bennee@linaro.org>
2024-02-09 17:52:40 +00:00
Ilya Leoshkevich
0a0d87c9b8 gdbstub: Add syscall entry/return hooks
The upcoming syscall catchpoint support needs to get control on syscall
entry and return. Provide the necessary hooks for that, which are
no-ops for now.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240202152506.279476-4-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240207163812.3231697-13-alex.bennee@linaro.org>
2024-02-09 17:52:40 +00:00
Ilya Leoshkevich
8b7fcb8ed1 gdbstub: Allow specifying a reason in stop packets
The upcoming syscall catchpoint support needs to send stop packets with
an associated reason to GDB. Add an extra parameter to gdb_handlesig()
for that, and rename it to gdb_handlesig_reason(). Provide a
compatibility wrapper with an old name.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20240202152506.279476-3-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240207163812.3231697-12-alex.bennee@linaro.org>
2024-02-09 17:52:40 +00:00
Clément Chigot
e216256ae9 gdbstub: replace exit calls with proper shutdown for softmmu
This replaces the exit calls by shutdown requests, ensuring a proper
cleanup of Qemu. Features like net/vhost-vdpa.c are expecting
qemu_cleanup to be called to remove their last residuals.

Signed-off-by: Clément Chigot <chigot@adacore.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231003071427.188697-6-chigot@adacore.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2023-10-12 12:36:37 +10:00
Alex Bennée
d0e5fa849d gdbstub: replace global gdb_has_xml with a function
Try and make the self reported global hack a little less hackish by
providing a query function instead. As gdb_has_xml was always set if
we negotiated XML we can now use the presence of ->target_xml as the
test instead.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230829161528.2707696-12-alex.bennee@linaro.org>
2023-08-30 14:57:56 +01:00
Matheus Tavares Bernardino
758370052f gdbstub: only send stop-reply packets when allowed to
GDB's remote serial protocol allows stop-reply messages to be sent by
the stub either as a notification packet or as a reply to a GDB command
(provided that the cmd accepts such a response). QEMU currently does not
implement notification packets, so it should only send stop-replies
synchronously and when requested. Nevertheless, it still issues
unsolicited stop messages through gdb_vm_state_change().

Although this behavior doesn't seem to cause problems with GDB itself
(the messages are just ignored), it can impact other debuggers that
implement the GDB remote serial protocol, like hexagon-lldb. Let's
change the gdbstub to send stop messages only as a response to a
previous GDB command that accepts such a reply.

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <a49c0897fc22a6a7827c8dfc32aef2e1d933ec6b.1683214375.git.quic_mathbern@quicinc.com>
2023-05-18 12:40:52 -07:00
Alex Bennée
131f387d74 gdbstub: split out softmmu/user specifics for syscall handling
Most of the syscall code is config agnostic aside from the size of
target_ulong. In preparation for the next patch move the final bits
of specialisation into the appropriate user and softmmu helpers.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230302190846.2593720-26-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-26-richard.henderson@linaro.org>
2023-03-07 20:44:09 +00:00
Alex Bennée
c566080cd3 gdbstub: move syscall handling to new file
Our GDB syscall support is the last chunk of code that needs target
specific support so move it to a new file. We take the opportunity to
move the syscall state into its own singleton instance and add in a
few helpers for the main gdbstub to interact with the module.

I also moved the gdb_exit() declaration into syscalls.h as it feels
pretty related and most of the callers of it treat it as such.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-22-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-22-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
505601d580 gdbstub: specialise stub_can_reverse
Currently we only support replay for softmmu mode so it is a constant
false for user-mode.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-18-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-18-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
7ea0c33def gdbstub: introduce gdb_get_max_cpus
This is needed for handling vcont packets as the way of calculating
max cpus vhanges between user and softmmu mode.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-17-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-17-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
589a58672e gdbstub: specialise target_memory_rw_debug
The two implementations are different enough to encourage having a
specialisation and we can move some of the softmmu only stuff out of
gdbstub.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-16-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-16-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
8a2025b36b gdbstub: specialise handle_query_attached
In both user and softmmu cases we are just replying with a constant.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-15-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-15-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
a7e0f9bd2a gdbstub: abstract target specific details from gdb_put_packet_binary
We unfortunately handle the checking of packet acknowledgement
differently for user and softmmu modes. Abstract the user mode stuff
behind gdb_got_immediate_ack with a stub for softmmu.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-14-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-14-richard.henderson@linaro.org>
2023-03-07 20:44:08 +00:00
Alex Bennée
d96bf49ba8 gdbstub: move chunks of user code into own files
The process was pretty similar to the softmmu move except we take the
time to split stuff between user.c and user-target.c to avoid as much
target specific compilation as possible. We also start to make use of
our shiny new header scheme so the user-only helpers can be included
without the rest of the exec/gsbstub.h cruft.

As before we split some functions into user and softmmu versions

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-12-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-12-richard.henderson@linaro.org>
2023-03-07 20:44:04 +00:00
Alex Bennée
9455762f58 gdbstub: fix-up copyright and license files
When I started splitting gdbstub apart I was a little too boilerplate
with my file headers. Fix up to carry over Fabrice's copyright and the
LGPL license header.

Fixes: ae7467b1ac (gdbstub: move breakpoint logic to accel ops)
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-3-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-3-richard.henderson@linaro.org>
2023-03-07 17:06:20 +00:00
Philippe Mathieu-Daudé
55b5b8e928 gdbstub: Use vaddr type for generic insert/remove_breakpoint() API
Both insert/remove_breakpoint() handlers are used in system and
user emulation. We can not use the 'hwaddr' type on user emulation,
we have to use 'vaddr' which is defined as "wide enough to contain
any #target_ulong virtual address".

gdbstub.c doesn't require to include "exec/hwaddr.h" anymore.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221216215519.5522-4-philmd@linaro.org>
2023-02-27 22:29:01 +01:00
Alex Bennée
a48e7d9e52 gdbstub: move guest debug support check to ops
This removes the final hard coding of kvm_enabled() in gdbstub and
moves the check to an AccelOps.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Message-Id: <20220929114231.583801-46-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00
Alex Bennée
ae7467b1ac gdbstub: move breakpoint logic to accel ops
As HW virtualization requires specific support to handle breakpoints
lets push out special casing out of the core gdbstub code and into
AccelOpsClass. This will make it easier to add other accelerator
support and reduces some of the stub shenanigans.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Message-Id: <20220929114231.583801-45-alex.bennee@linaro.org>
2022-10-06 11:53:41 +01:00