@@ -193,6 +193,11 @@ bool gdb_handled_syscall(void);
void gdb_disable_syscalls(void);
void gdb_syscall_reset(void);
+/* user/softmmu specific signal handling */
+void gdb_pre_syscall_handling(void);
+bool gdb_send_syscall_now(void);
+void gdb_post_syscall_handling(void);
+
/*
* Break/Watch point support - there is an implementation for softmmu
* and user mode.
@@ -101,6 +101,30 @@ static void gdb_chr_event(void *opaque, QEMUChrEvent event)
}
}
+/*
+ * In softmmu mode we stop the VM and wait to send the syscall packet
+ * until notification that the CPU has stopped. This must be done
+ * because if the packet is sent now the reply from the syscall
+ * request could be received while the CPU is still in the running
+ * state, which can cause packets to be dropped and state transition
+ * 'T' packets to be sent while the syscall is still being processed.
+ */
+
+void gdb_pre_syscall_handling(void)
+{
+ vm_stop(RUN_STATE_DEBUG);
+}
+
+bool gdb_send_syscall_now(void)
+{
+ return false;
+}
+
+void gdb_post_syscall_handling(void)
+{
+ qemu_cpu_kick(gdbserver_state.c_cpu);
+}
+
static void gdb_vm_state_change(void *opaque, bool running, RunState state)
{
CPUState *cpu = gdbserver_state.c_cpu;
@@ -102,9 +102,10 @@ void gdb_do_syscallv(gdb_syscall_complete_cb cb, const char *fmt, va_list va)
}
gdbserver_syscall_state.current_syscall_cb = cb;
-#ifndef CONFIG_USER_ONLY
- vm_stop(RUN_STATE_DEBUG);
-#endif
+
+ /* user/softmmu specific handling */
+ gdb_pre_syscall_handling();
+
p = &gdbserver_syscall_state.syscall_buf[0];
p_end = &gdbserver_syscall_state.syscall_buf[sizeof(gdbserver_syscall_state.syscall_buf)];
*(p++) = 'F';
@@ -138,24 +139,13 @@ void gdb_do_syscallv(gdb_syscall_complete_cb cb, const char *fmt, va_list va)
}
}
*p = 0;
-#ifdef CONFIG_USER_ONLY
- gdb_put_packet(gdbserver_syscall_state.syscall_buf);
- /* Return control to gdb for it to process the syscall request.
- * Since the protocol requires that gdb hands control back to us
- * using a "here are the results" F packet, we don't need to check
- * gdb_handlesig's return value (which is the signal to deliver if
- * execution was resumed via a continue packet).
- */
- gdb_handlesig(gdbserver_state.c_cpu, 0);
-#else
- /* In this case wait to send the syscall packet until notification that
- the CPU has stopped. This must be done because if the packet is sent
- now the reply from the syscall request could be received while the CPU
- is still in the running state, which can cause packets to be dropped
- and state transition 'T' packets to be sent while the syscall is still
- being processed. */
- qemu_cpu_kick(gdbserver_state.c_cpu);
-#endif
+
+ if (gdb_send_syscall_now()) { /* true only for *-user */
+ gdb_put_packet(gdbserver_syscall_state.syscall_buf);
+ }
+
+ /* user/softmmu specific handling */
+ gdb_post_syscall_handling();
}
void gdb_do_syscall(gdb_syscall_complete_cb cb, const char *fmt, ...)
@@ -467,3 +467,27 @@ void gdb_breakpoint_remove_all(CPUState *cs)
{
cpu_breakpoint_remove_all(cs, BP_GDB);
}
+
+/*
+ * For user-mode syscall support we send the system call immediately
+ * and then return control to gdb for it to process the syscall request.
+ * Since the protocol requires that gdb hands control back to us
+ * using a "here are the results" F packet, we don't need to check
+ * gdb_handlesig's return value (which is the signal to deliver if
+ * execution was resumed via a continue packet).
+ */
+
+void gdb_pre_syscall_handling(void)
+{
+ return;
+}
+
+bool gdb_send_syscall_now(void)
+{
+ return true;
+}
+
+void gdb_post_syscall_handling(void)
+{
+ gdb_handlesig(gdbserver_state.c_cpu, 0);
+}
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> --- gdbstub/internals.h | 5 +++++ gdbstub/softmmu.c | 24 ++++++++++++++++++++++++ gdbstub/syscalls.c | 32 +++++++++++--------------------- gdbstub/user.c | 24 ++++++++++++++++++++++++ 4 files changed, 64 insertions(+), 21 deletions(-)