The usual semihosting behaviour is to process the system calls locally and
return; unfortuantelly the initial implementation dinamically changed the
target to GDB during debug sessions, which, for the usual arm-none-eabi-gdb,
is not implemented. The result was that during debug sessions the semihosting
calls were discarded.
This patch adds a configuration variable and an option to set it on the
command line:
-semihosting-config [enable=on|off,]target=native|gdb|auto
This option enables semihosting and defines where the semihosting calls will
be addressed, to QEMU ('native') or to GDB ('gdb'). The default is auto, which
means 'gdb' during debug sessions and 'native' otherwise.
Signed-off-by: Liviu Ionescu <ilg@livius.net>
Message-id: 1416341957-9796-1-git-send-email-ilg@livius.net
[PMM: moved declaration and definition of semihosting_target to
gdbstub.h and gdbstub.c to fix build failure on linux-user]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
While using qemu with gdb "target remote" to debug an application that uses
fork and exec, the qemu process receives SIGSTOP every time the forked process
terminates (sending SIGCHLD).
This is caused by a missing call to gdb_signal_to_target in gdbstub.c, which
is fixed by this patch:
Signed-off-by: Martin Simmons <martin@lispworks.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
GDB assumes that watchpoint set via the gdbstub remote protocol will
behave in the same way as hardware watchpoints for the target. In
particular, whether the CPU stops with the PC before or after the insn
which triggers the watchpoint is target dependent. Allow guest CPU
code to specify which behaviour to use. This fixes a bug where with
guest CPUs which stop before the accessing insn GDB would manually
step forward over what it thought was the insn and end up one insn
further forward than it should be.
We set this flag for the CPU architectures which set
gdbarch_have_nonsteppable_watchpoint in gdb 7.7:
ARM, CRIS, LM32, MIPS and Xtensa.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Michael Walle <michael@walle.cc> (for lm32)
Message-id: 1410545057-14014-1-git-send-email-peter.maydell@linaro.org
This patch initializes monitor for gdbstub with the qemu_chr_alloc function
instead of just allocating the memory. Initialization function call
is required, because it also creates chr_write_lock mutex, which is used
when writing to this character device.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After reporting the GUEST_PANICKED monitor event, QEMU stops the VM.
The reason for this is that events are edge-triggered, and can be lost if
management dies at the wrong time. Stopping a panicked VM lets management
know of a panic even if it has crashed; management can learn about the
panic when it restarts and queries running QEMU processes. The downside
is of course that the VM will be paused while management is not running,
but that is acceptable if it only happens with explicit "-device pvpanic".
Upon learning of a panic, management (if configured to do so) can pick a
variety of behaviors: leave the VM paused, reset it, destroy it. In
addition to all of these behaviors, it is possible to dump the VM core
from the host.
However, right now, the panicked state is irreversible, and can only be
exited by resetting the machine. This means that any policy decision
is entirely in the hands of the host. In particular there is no way to
use the "reboot on panic" option together with pvpanic.
This patch makes the panicked state reversible (and removes various
workarounds that were there because of the state being irreversible).
With this change, management has a wider set of possible policies: it
can just log the crash and leave policy to the guest, it can leave the
VM paused. In particular, the "log the crash and continue" is implemented
simply by sending a "cont" as soon as management learns about the panic.
Management could also implement the "irreversible paused state" itself.
And again, all such actions can be coupled with dumping the VM core.
Unfortunately we cannot change the behavior of 1.6.0. Thus, even if
it uses "-device pvpanic", management should check for "cont" failures.
If "cont" fails, management can then log that the VM remained paused
and urge the administrator to update QEMU.
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
SO_REUSEADDR should be avoided on Windows but is desired on other operating
systems. So instead of setting it we call socket_set_fast_reuse that will result
in the appropriate behaviour on all operating systems.
Signed-off-by: Sebastian Ottlik <ottlik@fzi.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Commit a0e372f0c4 reorganized the register
counting for GDB. While it seems correct not to let the total number of
registers skyrocket in an SMP scenario through a static variable, the
distinction between total register count and 'g' packet register count
(last_reg vs. num_g_regs) got lost among the way.
Fix this by introducing CPUState::gdb_num_g_regs and using that in
gdb_handle_packet().
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org (stable-1.6)
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Replace the GDB_CORE_XML define in gdbstub.c with a CPUClass field.
Use first_cpu for qSupported and qXfer:features:read: for now.
Add a stub for xml_builtin.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Completes migration of target-specific code to new target-*/gdbstub.c.
Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (for xtensa)
Signed-off-by: Andreas Färber <afaerber@suse.de>
This avoids polluting the global namespace with a non-prefixed macro and
makes it obvious in the call sites that we return.
Semi-automatic conversion using, e.g.,
sed -i 's/GET_REGL(/return gdb_get_regl(mem_buf, /g' target-*/gdbstub.c
followed by manual tweaking for sparc's GET_REGA() and Coding Style.
Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (for xtensa)
Signed-off-by: Andreas Färber <afaerber@suse.de>
CPUState::gdb_num_regs replaces num_g_regs.
CPUClass::gdb_num_core_regs replaces NUM_CORE_REGS.
Allows building gdb_register_coprocessor() for xtensa, too.
As a side effect this should fix coprocessor register numbering for SMP.
Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (for xtensa)
Signed-off-by: Andreas Färber <afaerber@suse.de>
GET_REG*() macros include a return statement, thus no need for break.
Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Signed-off-by: Andreas Färber <afaerber@suse.de>
Add braces, replace tabs, remove trailing whitespace, drop space before
parenthesis and place break etc. below case statements.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Make inline target_memory_rw_debug() always available and change its
argument to CPUState. Let it check if CPUClass::memory_rw_debug provides
a specialized callback and fall back to cpu_memory_rw_debug() otherwise.
The only overriding implementation is for 32-bit sparc.
This prepares for changing GDBState::g_cpu to CPUState.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Callback implementations were specific to arm and m68k, so can easily
cast to ARMCPU and M68kCPU respectively.
Prepares for changing GDBState::c_cpu to CPUState.
Signed-off-by: Andreas Färber <afaerber@suse.de>
CPUArchState is no longer directly used since converting CPU loops to
CPUState.
Prepares for changing GDBState::c_cpu to CPUState.
Signed-off-by: Andreas Färber <afaerber@suse.de>
In particular reindent to 4 instead of 2 spaces.
Prepares for changing cpu_single_step() argument in gdb_handlesig().
Signed-off-by: Andreas Färber <afaerber@suse.de>
This moves setting the Program Counter from gdbstub into target code.
Use vaddr type as upper-bound replacement for target_ulong.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Since first_cpu/next_cpu are CPUState, CPUArchState is no longer needed.
This resolves a NULL pointer dereference of query_cpu, introduced
with commit 182735efaf and reported by
TeLeMan and Max Filippov.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Move next_cpu from CPU_COMMON to CPUState.
Move first_cpu variable to qom/cpu.h.
gdbstub needs to use CPUState::env_ptr for now.
cpu_copy() no longer needs to save and restore cpu_next.
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[AF: Rebased, simplified cpu_copy()]
Signed-off-by: Andreas Färber <afaerber@suse.de>
This reverts commit c52a6b67c1, which
replaced cpu_index() with cpu_index field, leading to deviation from
thread ID for NTPL and off-by-one otherwise.
Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Use CPUState::env_ptr for now.
Prepares for changing cpu_handle_guest_debug() argument to CPUState.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andreas Färber <afaerber@suse.de>
It no longer depends on CPUArchState, so move it to qom/cpu.c.
Prepares for changing GDBState::c_cpu to CPUState.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Liviu Ionescu
Martin Simmons
Peter Maydell
Pavel Dovgalyuk
Andreas Färber
Paolo Bonzini
Sebastian Ottlik