Commit Graph

402 Commits

Author SHA1 Message Date
Maxim Levitsky 12bc5b4cd5 gdbstub, kvm: let KVM report supported singlestep flags
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[Extracted from Maxim's patch into a separate commit. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20211111110604.207376-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-10 09:47:18 +01:00
Maxim Levitsky ecd39d620b gdbstub: reject unsupported flags in handle_set_qemu_sstep
handle_query_qemu_sstepbits is reporting NOIRQ and NOTIMER bits
even if they are not supported (as is the case with record/replay).
Instead, store the supported singlestep flags and reject
any unsupported bits in handle_set_qemu_sstep.  This removes
the need for the get_sstep_flags() wrapper.

While at it, move the variables in GDBState, instead of using
global variables.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[Extracted from Maxim's patch into a separate commit. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20211111110604.207376-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-10 09:47:18 +01:00
Alex Bennée a8e537fa4d gdbstub: handle a potentially racing TaskState
When dealing with multi-threaded userspace programs there is a race
condition with the addition of cpu->opaque (aka TaskState). This is
due to cpu_copy calling cpu_create which updates the global vCPU list.
However the task state isn't set until later. This shouldn't be a
problem because the new thread can't have executed anything yet but
the gdbstub code does liberally iterate through the CPU list in
various places.

This sticking plaster ensure the not yet fully realized vCPU is given
an pid of -1 which should be enough to ensure it doesn't show up
anywhere else.

In the longer term I think the code that manages the association
between vCPUs and attached GDB processes could do with a clean-up and
re-factor.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/730
Message-Id: <20211129140932.4115115-6-alex.bennee@linaro.org>
2021-11-29 15:13:12 +00:00
Pavel Labath 4a82be77de gdbstub: Switch to the thread receiving a signal
Respond with Txxthread:yyyy; instead of a plain Sxx to indicate which
thread received the signal. Otherwise, the debugger will associate it
with the main one. Also automatically select this thread, as that is
what gdb expects.

Signed-off-by: Pavel Labath <pavel@labath.sk>
Message-Id: <20211019174953.36560-1-pavel@labath.sk>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211026102234.3961636-29-alex.bennee@linaro.org>
2021-11-04 10:32:01 +00:00
Peter Maydell 85b4fa0cd1 linux-user: Don't include gdbstub.h in qemu.h
Currently the linux-user qemu.h pulls in gdbstub.h. There's no real reason
why it should do this; include it directly from the C files which require
it, and drop the include line in qemu.h.

(Note that several of the C files previously relying on this indirect
include were going out of their way to only include gdbstub.h conditionally
on not CONFIG_USER_ONLY!)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210908154405.15417-9-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-09-13 20:35:45 +02:00
Peter Maydell fdcdf54d1e gdbstub: Zero-initialize sockaddr structs
Zero-initialize sockaddr_in and sockaddr_un structs that we're about
to fill in and pass to bind() or connect(), to ensure we don't leave
possible implementation-defined extension fields as uninitialized
garbage.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210813150506.7768-3-peter.maydell@linaro.org
2021-08-26 17:02:00 +01:00
Alex Bennée ed12f5b4ef gdbstub: tidy away reverse debugging check into function
In theory we don't need an actual record/replay to enact reverse
debugging on a purely deterministic system (i.e one with no external
inputs running under icount). Tidy away the logic into a little
function.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210520174303.12310-8-alex.bennee@linaro.org>
2021-05-25 16:52:50 +01:00
Alex Bennée 26a16181fa gdbstub: Replace GdbCmdContext with plain g_array()
Instead of jumping through hoops let glib deal with both tracking the
number of elements and auto freeing the memory once we are done. This
allows is to drop the usage of ALLOCA(3) which the man-page mentions
its "use is discouraged".

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210520174303.12310-6-alex.bennee@linaro.org>
2021-05-25 16:52:50 +01:00
Philippe Mathieu-Daudé 305bea066d gdbstub: Constify GdbCmdParseEntry
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210505170055.1415360-3-philmd@redhat.com>
Message-Id: <20210520174303.12310-5-alex.bennee@linaro.org>
2021-05-25 16:52:50 +01:00
Thomas Huth 4c386f8064 Do not include sysemu/sysemu.h if it's not really necessary
Stop including sysemu/sysemu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:50 +02:00
Peter Maydell 6f34661b6c Pull request
-----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEEzS913cjjpNwuT1Fz8ww4vT8vvjwFAmBJQHkSHGxhdXJlbnRA
 dml2aWVyLmV1AAoJEPMMOL0/L748EdsP/2U2CGTM95tjDunTs9uZV/7zM6PWt85M
 vAPItNVU2jYPfzmaJN8twrzlj0PEDhvB9Q+OJjE4HEGxEbPcdblLg/R6Zs/EaWuY
 N6oKHPXnOnHb+e80UUJdiAq+Y5RUnJbb5L3ArycnVzBgws+Oj3DtqjB2VDccY4C/
 Gkt23tZ7ikU4958e5VBqW2NUUrr+BQO0mqsW+sbbeE3WPj75NQc6srvS3TWvsg7W
 OYEyVYwm52/q2W/1a3Knfv/YO6UU9NGMpGyDLD2kwQwKbgUWYLW2BiWVwOAUldo9
 De3nfKbKnFezLCZAZro20lfCa/aKwNGCOXWzlrKxqUQCmGYUx7gM1+3ahrSd5N0v
 zUgLdZm7O428ZHL6GujWGLA1UwwzpM9X3P3yo4c0S1J6fHypbI6a9jtewrUFvFgP
 TuQ7dp6cn2DTBYUcsrWilPHbTZMADYQNRD/xUtKqalYBEWy3FX5W75+OYBJKKh+X
 Qip68m6JBzgkszXhCcu6xlLb8ynZJr2VsHvtvIgf4NnLqNOIEgVLcMtoMZT8DPrp
 rIoRc5oUFz8zj5lHnJuLADBUvlCMqoCCoU3h2aqHwH8a7RGb180f+82BW9aBcb2u
 Jk+WgAhBUjWBBC97ReFgrINUD/qZRXVoOq8LthTuQSSyr/i1zq+oLM1F0EDXcMDm
 ssATku2IxL24
 =moUF
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-for-6.0-pull-request' into staging

Pull request

# gpg: Signature made Wed 10 Mar 2021 21:56:09 GMT
# gpg:                using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C
# gpg:                issuer "laurent@vivier.eu"
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>" [full]
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>" [full]
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>" [full]
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier2/tags/trivial-branch-for-6.0-pull-request: (22 commits)
  sysemu: Let VMChangeStateHandler take boolean 'running' argument
  sysemu/runstate: Let runstate_is_running() return bool
  hw/lm32/Kconfig: Have MILKYMIST select LM32_DEVICES
  hw/lm32/Kconfig: Rename CONFIG_LM32 -> CONFIG_LM32_DEVICES
  hw/lm32/Kconfig: Introduce CONFIG_LM32_EVR for lm32-evr/uclinux boards
  qemu-common.h: Update copyright string to 2021
  tests/fp/fp-test: Replace the word 'blacklist'
  qemu-options: Replace the word 'blacklist'
  seccomp: Replace the word 'blacklist'
  scripts/tracetool: Replace the word 'whitelist'
  ui: Replace the word 'whitelist'
  virtio-gpu: Adjust code space style
  exec/memory: Use struct Object typedef
  fuzz-test: remove unneccessary debugging flags
  net: Use id_generate() in the network subsystem, too
  MAINTAINERS: Fix the location of tools manuals
  vhost_user_gpu: Drop dead check for g_malloc() failure
  backends/dbus-vmstate: Fix short read error handling
  target/hexagon/gen_tcg_funcs: Fix a typo
  hw/elf_ops: Fix a typo
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-03-11 18:55:27 +00:00
Philippe Mathieu-Daudé 6b5fe13786 semihosting: Move include/hw/semihosting/ -> include/semihosting/
We want to move the semihosting code out of hw/ in the next patch.

This patch contains the mechanical steps, created using:

  $ git mv include/hw/semihosting/ include/
  $ sed -i s,hw/semihosting,semihosting, $(git grep -l hw/semihosting)

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210226131356.3964782-2-f4bug@amsat.org>
Message-Id: <20210305135451.15427-2-alex.bennee@linaro.org>
2021-03-10 15:34:12 +00:00
Philippe Mathieu-Daudé 538f049704 sysemu: Let VMChangeStateHandler take boolean 'running' argument
The 'running' argument from VMChangeStateHandler does not require
other value than 0 / 1. Make it a plain boolean.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20210111152020.1422021-3-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-03-09 23:13:57 +01:00
Paolo Bonzini a9b1315f86 chardev: add nodelay option
The "delay" option was introduced as a way to enable Nagle's algorithm
with ",nodelay".  Since the short form for boolean options has now been
deprecated, introduce a more properly named "nodelay" option.  The "delay"
option remains as an undocumented option.

"delay" and "nodelay" are mutually exclusive.  Because the check is
done at consumption time, the code also rejects them if one of the
two is specified via -set.

Based-on: <20210226080526.651705-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 11:41:54 +01:00
Daniel P. Berrangé 87c9991a0c gdbstub: use preferred boolean option syntax
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210216191027.595031-2-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-25 14:14:33 +01:00
Richard Henderson 6e3dd75717 gdbstub: Fix handle_query_xfer_auxv
The main problem was that we were treating a guest address
as a host address with a mere cast.

Use the correct interface for accessing guest memory.  Do not
allow offset == auxv_len, which would result in an empty packet.

Fixes: 51c623b0de ("gdbstub: add support to Xfer:auxv:read: packet")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210128201831.534033-1-richard.henderson@linaro.org>
Message-Id: <20210202134001.25738-11-alex.bennee@linaro.org>
2021-02-08 10:55:15 +00:00
Alex Bennée b9e10c6c75 gdbstub: ensure we clean-up when terminated
If you kill the inferior from GDB we end up leaving our socket lying
around. Fix this by calling gdb_exit() first.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-10-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Alex Bennée 5ef0317f58 gdbstub: drop gdbserver_cleanup in favour of gdb_exit
Despite it's name it didn't actually clean-up so let us document
gdb_exit() better and use that.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-9-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Alex Bennée ad9dcb207b gdbstub: drop CPUEnv from gdb_exit()
gdb_exit() has never needed anything from env and I doubt we are going
to start now.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-8-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Lirong Yuan 51c623b0de gdbstub: add support to Xfer:auxv:read: packet
This allows gdb to access the target’s auxiliary vector,
which can be helpful for telling system libraries important details
about the hardware, operating system, and process.

Signed-off-by: Lirong Yuan <yuanzi@google.com>
[AJB: minor tweaks to test case, update MAINTAINERS, restrict to Linux]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200730193932.3654677-1-yuanzi@google.com>
Message-Id: <20210108224256.2321-7-alex.bennee@linaro.org>
2021-01-18 10:04:48 +00:00
Peter Maydell 3ddd903638 gdbstub: Correct misparsing of vCont C/S requests
In the vCont packet, two of the command actions (C and S) take an
argument specifying the signal to be sent to the process/thread, which is
sent as an ASCII string of two hex digits which immediately follow the
'C' or 'S' character.

Our code for parsing this packet accidentally skipped the first of the
two bytes of the signal value, because it started parsing the hex string
at 'p + 1' when the preceding code had already moved past the 'C' or
'S' with "cur_action = *p++".

This meant that we would only do the right thing for signals below
10, and would misinterpret the rest.  For instance, when the debugger
wants to send the process a SIGPROF (27 on x86-64) we mangle this into
a SIGSEGV (11).

Remove the accidental double increment.

Fixes: https://bugs.launchpad.net/qemu/+bug/1773743
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20201121210342.10089-1-peter.maydell@linaro.org
2020-12-15 12:04:29 +00:00
Pavel Dovgalyuk 56357d80fc replay: create temporary snapshot at debugger connection
When record/replay does not uses overlays for storing the snapshots,
user is not capable of issuing reverse debugging commands.
This patch adds creation of the VM snapshot on the temporary
overlay image, when the debugger connects to QEMU.
Therefore the execution can be rewind to the moment
of the debugger connection while debugging the virtual machine.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>

--

v6:
 - dropped unused error processing (suggested by Philippe Mathieu-Daudé)
Message-Id: <160174524096.12451.11651270339216758643.stgit@pasha-ThinkPad-X280>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-06 08:34:49 +02:00
Pavel Dovgalyuk cda382594b gdbstub: add reverse continue support in replay mode
This patch adds support of the reverse continue operation for gdbstub.
Reverse continue finds the last breakpoint that would happen in normal
execution from the beginning to the current moment.
Implementation of the reverse continue replays the execution twice:
to find the breakpoints that were hit and to seek to the last breakpoint.
Reverse continue loads the previous snapshot and tries to find the breakpoint
since that moment. If there are no such breakpoints, it proceeds to
the earlier snapshot, and so on. When no breakpoints or watchpoints were
hit at all, execution stops at the beginning of the replay log.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Message-Id: <160174522930.12451.6994758004725016836.stgit@pasha-ThinkPad-X280>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-06 08:34:49 +02:00
Pavel Dovgalyuk fda8458bd3 gdbstub: add reverse step support in replay mode
GDB remote protocol supports two reverse debugging commands:
reverse step and reverse continue.
This patch adds support of the first one to the gdbstub.
Reverse step is intended to step one instruction in the backwards
direction. This is not possible in regular execution.
But replayed execution is deterministic, therefore we can load one of
the prior snapshots and proceed to the desired step. It is equivalent
to stepping one instruction back.
There should be at least one snapshot preceding the debugged part of
the replay log.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

--

v4 changes:
 - inverted condition in cpu_handle_guest_debug (suggested by Alex Bennée)
Message-Id: <160174522341.12451.1498758422543765253.stgit@pasha-ThinkPad-X280>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-06 08:34:49 +02:00
Paolo Bonzini 243af0225a trace: switch position of headers to what Meson requires
Meson doesn't enjoy the same flexibility we have with Make in choosing
the include path.  In particular the tracing headers are using
$(build_root)/$(<D).

In order to keep the include directives unchanged,
the simplest solution is to generate headers with patterns like
"trace/trace-audio.h" and place forwarding headers in the source tree
such that for example "audio/trace.h" includes "trace/trace-audio.h".

This patch is too ugly to be applied to the Makefiles now.  It's only
a way to separate the changes to the tracing header files from the
Meson rewrite of the tracing logic.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:18:24 -04:00
Markus Armbruster 7a309cc95b qom: Change object_get_canonical_path_component() not to malloc
object_get_canonical_path_component() returns a malloced copy of a
property name on success, null on failure.

19 of its 25 callers immediately free the returned copy.

Change object_get_canonical_path_component() to return the property
name directly.  Since modifying the name would be wrong, adjust the
return type to const char *.

Drop the free from the 19 callers become simpler, add the g_strdup()
to the other six.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200714160202.3121879-4-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
2020-07-21 16:23:43 +02:00
Alex Bennée fcedd92086 gdbstub/linux-user: support debugging over a unix socket
While debugging over TCP is fairly straightforward now we have test
cases that want to orchestrate via make and currently a parallel build
fails as two processes can't use the same listening port. While system
emulation offers a wide cornucopia of connection methods thanks to the
chardev abstraction we are a little more limited for linux user.
Thankfully the programming API for a TCP socket and a local UNIX
socket is pretty much the same once it's set up.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200430190122.4592-7-alex.bennee@linaro.org>
2020-05-06 09:29:26 +01:00
Alex Bennée e0a1e20847 gdbstub: eliminate gdbserver_fd global
We don't really need to track this fd beyond the initial creation of
the socket. We already know if the system has been initialised by
virtue of the gdbserver_state so lets remove it. This makes the later
re-factoring easier.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200430190122.4592-6-alex.bennee@linaro.org>
2020-05-06 09:29:26 +01:00
Denis Plotnikov 076b2fadb5 gdbstub: fix compiler complaining
./gdbstub.c: In function ‘handle_query_thread_extra’:
        /usr/include/glib-2.0/glib/glib-autocleanups.h:28:10:
    error: ‘cpu_name’ may be used uninitialized in this function
    [-Werror=maybe-uninitialized]
        g_free (*pp);
               ^
    ./gdbstub.c:2063:26: note: ‘cpu_name’ was declared here
        g_autofree char *cpu_name;
                         ^
    cc1: all warnings being treated as errors

Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Message-Id: <20200326151407.25046-1-dplotnikov@virtuozzo.com>
Reported-by: Euler Robot <euler.robot@huawei.com>
Reported-by: Chen Qun <kuhn.chenqun@huawei.com>
Reviewed-by: Miroslav Rezanina <mrezanin@redhat.com>
Message-Id: <20200325092137.24020-1-kuhn.chenqun@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200403191150.863-7-alex.bennee@linaro.org>
2020-04-07 16:19:49 +01:00
Changbin Du 3bc2609d47 gdbstub: Fix single-step issue by confirming 'vContSupported+' feature to gdb
Recently when debugging an arm32 system on qemu, I found sometimes the
single-step command (stepi) is not working. This can be reproduced by
below steps:
 1) start qemu-system-arm -s -S .. and wait for gdb connection.
 2) start gdb and connect to qemu. In my case, gdb gets a wrong value
    (0x60) for PC, which is an another bug.
 3) After connected, type 'stepi' and expect it will stop at next ins.

But, it has never stopped. This because:
 1) We doesn't report ‘vContSupported’ feature to gdb explicitly and gdb
    think we do not support it. In this case, gdb use a software breakpoint
    to emulate single-step.
 2) Since gdb gets a wrong initial value of PC, then gdb inserts a
    breakpoint to wrong place (PC+4).

Not only for the arm target, Philippe has also encountered this on MIPS.
Probably gdb has different assumption for different architectures.

Since we do support ‘vContSupported’ query command, so let's tell gdb that
we support it.

Before this change, gdb send below 'Z0' packet to implement single-step:
gdb_handle_packet: Z0,4,4

After this change, gdb send "vCont;s.." which is expected:
gdb_handle_packet: vCont?
put_packet: vCont;c;C;s;S
gdb_handle_packet: vCont;s:p1.1;c:p1.-1

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200221002559.6768-1-changbin.du@gmail.com>
[AJB: fix for static gdbstub]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luc Michel <luc.michel@greensocs.com>
Message-Id: <20200316172155.971-29-alex.bennee@linaro.org>
2020-03-17 17:38:52 +00:00
Damien Hedde d86b4672f2 gdbstub: do not split gdb_monitor_write payload
Since we can now send packets of arbitrary length:
simplify gdb_monitor_write() and send the whole payload
in one packet.

Suggested-by: Luc Michel <luc.michel@greensocs.com>
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20191211160514.58373-3-damien.hedde@greensocs.com>
Message-Id: <20200316172155.971-28-alex.bennee@linaro.org>
2020-03-17 17:38:51 +00:00
Damien Hedde d116e813a5 gdbstub: change GDBState.last_packet to GByteArray
Remove the packet size upper limit by using a GByteArray
instead of a statically allocated array for last_packet.
Thus we can now send big packets.

Also remove the last_packet_len field and use last_packet->len
instead.

Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20191211160514.58373-2-damien.hedde@greensocs.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200316172155.971-27-alex.bennee@linaro.org>
2020-03-17 17:38:47 +00:00
Alex Bennée a010bdbe71 gdbstub: extend GByteArray to read register helpers
Instead of passing a pointer to memory now just extend the GByteArray
to all the read register helpers. They can then safely append their
data through the normal way. We don't bother with this abstraction for
write registers as we have already ensured the buffer being copied
from is the correct size.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>

Message-Id: <20200316172155.971-15-alex.bennee@linaro.org>
2020-03-17 17:38:38 +00:00
Alex Bennée 4a25f1b97a gdbstub: move mem_buf to GDBState and use GByteArray
This is in preparation for further re-factoring of the register API
with the rest of the code. Theoretically the read register function
could overwrite the MAX_PACKET_LENGTH buffer although currently all
registers are well within the size range.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Tested-by: Damien Hedde <damien.hedde@greensocs.com>

Message-Id: <20200316172155.971-10-alex.bennee@linaro.org>
2020-03-17 17:38:38 +00:00
Alex Bennée 308f9e88b2 gdbstub: move str_buf to GDBState and use GString
Rather than having a static buffer replace str_buf with a GString
which we know can grow on demand. Convert the internal functions to
take a GString instead of a char * and length.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Tested-by: Damien Hedde <damien.hedde@greensocs.com>
Message-Id: <20200316172155.971-9-alex.bennee@linaro.org>
2020-03-17 17:38:38 +00:00
Alex Bennée a346af3e35 gdbstub: stop passing GDBState * around and use global
We only have one GDBState which should be allocated at the time we
process any commands. This will make further clean-up a bit easier.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Message-Id: <20200316172155.971-8-alex.bennee@linaro.org>
2020-03-17 17:38:38 +00:00
Alex Bennée 8d98c445dc gdbstub: make GDBState static and have common init function
Instead of allocating make this entirely static. We shall reduce the
size of the structure in later commits and dynamically allocate parts
of it. We introduce an init and reset helper function to keep all the
manipulation in one place.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>

Message-Id: <20200316172155.971-7-alex.bennee@linaro.org>
2020-03-17 17:38:37 +00:00
Kevin Wolf 8e9119a807 hmp: Fail gracefully if chardev is already in use
Trying to attach a HMP monitor to a chardev that is already in use
results in a crash because monitor_init_hmp() passes &error_abort to
qemu_chr_fe_init():

$ ./x86_64-softmmu/qemu-system-x86_64 --chardev stdio,id=foo --mon foo --mon foo
QEMU 4.2.50 monitor - type 'help' for more information
(qemu) Unexpected error in qemu_chr_fe_init() at chardev/char-fe.c:220:
qemu-system-x86_64: --mon foo: Device 'foo' is in use
Abgebrochen (Speicherabzug geschrieben)

Fix this by allowing monitor_init_hmp() to return an error and passing
any error in qemu_chr_fe_init() to its caller instead of aborting.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200224143008.13362-19-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-03-06 17:21:28 +01:00
Philippe Mathieu-Daudé 083b266f69 chardev: Use QEMUChrEvent enum in IOEventHandler typedef
The Chardev events are listed in the QEMUChrEvent enum.

By using the enum in the IOEventHandler typedef we:

- make the IOEventHandler type more explicit (this handler
  process out-of-band information, while the IOReadHandler
  is in-band),
- help static code analyzers.

This patch was produced with the following spatch script:

  @match@
  expression backend, opaque, context, set_open;
  identifier fd_can_read, fd_read, fd_event, be_change;
  @@
  qemu_chr_fe_set_handlers(backend, fd_can_read, fd_read, fd_event,
                           be_change, opaque, context, set_open);

  @depends on match@
  identifier opaque, event;
  identifier match.fd_event;
  @@
   static
  -void fd_event(void *opaque, int event)
  +void fd_event(void *opaque, QEMUChrEvent event)
   {
   ...
   }

Then the typedef was modified manually in
include/chardev/char-fe.h.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20191218172009.8868-15-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 11:15:35 +01:00
Sandra Loosemore c6ee95216b gdbstub: Fix handler for 'F' packet
Handling of the 'F' packet has been broken since commit
4b20fab101, which converted it to use
the new packet parsing infrastructure.  Per the GDB RSP specification

https://sourceware.org/gdb/current/onlinedocs/gdb/The-F-Reply-Packet.html

the second parameter may be omitted, but the rewritten implementation
was failing to recognize this case.  The result was that QEMU was
repeatedly resending the fileio request and ignoring GDB's replies of
successful completion.  This patch restores the behavior of the
previous code in allowing the errno parameter to be omitted and
passing 0 to the callback in that case.

Signed-off-by: Sandra Loosemore <sandra@codesourcery.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20190827223317.8614-1-sandra@codesourcery.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-08-28 10:11:15 +01:00
Ramiro Polla 2bdec39848 gdbstub: Fix handling of '!' packet with new infra
Since the '!' packet is not handled by the new infrastructure,
gdb_handle_packet() would call run_cmd_parser() with a NULL cmd_parser
value, which would lead to an unsupported packet ("$#00") being sent,
which could confuse the gdb client.

This also has a side-effect of speeding up the initial connection with
gdb.

Fixes: 3e2c12615b ("gdbstub: Implement deatch (D pkt) with new infra")
Signed-off-by: Ramiro Polla <ramiro.polla@gmail.com>
Message-Id: <20190805190901.14072-1-ramiro.polla@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-08-28 10:11:06 +01:00
Markus Armbruster 54d31236b9 sysemu: Split sysemu/runstate.h off sysemu/sysemu.h
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator.  Evidence:

* It's included widely: in my "build everything" tree, changing
  sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
  objects (not counting tests and objects that don't depend on
  qemu/osdep.h, down from 5400 due to the previous two commits).

* It pulls in more than a dozen additional headers.

Split stuff related to run state management into its own header
sysemu/runstate.h.

Touching sysemu/sysemu.h now recompiles some 850 objects.  qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200.  Touching new sysemu/runstate.h recompiles some 500 objects.

Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
2019-08-16 13:37:36 +02:00
Alex Bennée 94b2a62bb6 gdbstub: revert to previous set_reg behaviour
The refactoring of handle_set_reg missed the fact we previously had
responded with an empty packet when we were not using XML based
protocols. This broke the fallback behaviour for architectures that
don't have registers defined in QEMU's gdb-xml directory.

Revert to the previous behaviour and clean up the commentary for what
is going on.

Fixes: 62b3320bdd
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Jon Doron <arilou@gmail.com>
2019-07-10 10:54:46 +01:00
Alex Bennée 42a0959648 gdbstub: add some notes to the header comment
Add a link to the remote protocol spec and an SPDX tag.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-07-10 10:54:41 +01:00
Like Xu 5cc8767d05 general: Replace global smp variables with smp machine properties
Basically, the context could get the MachineState reference via call
chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode.

A local variable of the same name would be introduced in the declaration
phase out of less effort OR replace it on the spot if it's only used
once in the context. No semantic changes.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-07-05 17:07:36 -03:00
Kevin Wolf fbfc29e3bf monitor: Replace monitor_init() with monitor_init_{hmp, qmp}()
Most callers know which monitor type they want to have. Instead of
calling monitor_init() with flags that can describe both types of
monitors, make monitor_init_{hmp,qmp}() public interfaces that take
specific bools instead of flags and call these functions directly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20190613153405.24769-15-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2019-06-18 08:14:17 +02:00
Jon Doron ab4752ec8d gdbstub: Implement qemu physical memory mode
Add a new query/set which changes the memory GDB sees to physical memory
only.

gdb> maint packet qqemu.PhyMemMode
will reply the current phy_mem_mode state (1 for enabled, 0 for disabled)
gdb> maint packet Qqemu.PhyMemMode:1
Will make GDB read/write only to physical memory, set to 0 to disable

Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20190529064148.19856-21-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-06-12 17:53:23 +01:00
Jon Doron 3f1cbac73a gdbstub: Clear unused variables in gdb_handle_packet
Signed-off-by: Jon Doron <arilou@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190529064148.19856-20-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-06-12 17:53:23 +01:00
Jon Doron 7009d57924 gdbstub: Implement target halted (? pkt) with new infra
Note: The user-mode thread-id has been correctly reported since bd88c780e6

Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20190529064148.19856-19-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-06-12 17:53:23 +01:00
Jon Doron 2704efad51 gdbstub: Implement generic set/query (Q/q pkt) with new infra
The generic set/query packets contains implementation for varioius
sub-commands which are required for GDB and also additional commands
which are QEMU specific.

To see which QEMU specific commands are available use the command
gdb> maintenance packet qqemu.Supported

Currently the only implemented QEMU specific command is the command
that sets the single step behavior.

gdb> maintenance packet qqemu.sstepbits
Will display the MASK bits used to control the single stepping.

gdb> maintenance packet qqemu.sstep
Will display the current value of the mask used when single stepping.

gdb> maintenance packet Qqemu.sstep:HEX_VALUE
Will change the single step mask.

Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20190529064148.19856-18-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-06-12 17:53:23 +01:00