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>

1 files changed, 6 insertions, 2 deletions

diff --git a/gdbstub.c b/gdbstub.c
index 36b85aa50e..23baaef40e 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -3138,8 +3138,12 @@ gdb_handlesig(CPUState *cpu, int sig)
     tb_flush(cpu);
 
     if (sig != 0) {
-        snprintf(buf, sizeof(buf), "S%02x", target_signal_to_gdb(sig));
-        put_packet(buf);
+        gdb_set_stop_cpu(cpu);
+        g_string_printf(gdbserver_state.str_buf,
+                        "T%02xthread:", target_signal_to_gdb(sig));
+        gdb_append_thread_id(cpu, gdbserver_state.str_buf);
+        g_string_append_c(gdbserver_state.str_buf, ';');
+        put_strbuf();
     }
     /* put_packet() might have detected that the peer terminated the
        connection.  */