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authorMaxim Levitsky <mlevitsk@redhat.com>2021-11-11 12:06:02 +0100
committerPaolo Bonzini <pbonzini@redhat.com>2021-12-10 09:47:18 +0100
commitecd39d620b0a3938dc3a80721e8aa436075d2916 (patch)
tree5dee9dab83c16649fa4d1bbe404f78cecab838ab /gdbstub.c
parent43709a0ca3b09e952bde3f38112f1d7fbf7c65b1 (diff)
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>
Diffstat (limited to 'gdbstub.c')
-rw-r--r--gdbstub.c75
1 files changed, 49 insertions, 26 deletions
diff --git a/gdbstub.c b/gdbstub.c
index 141d7bc4ec..a955175fd4 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -368,27 +368,10 @@ typedef struct GDBState {
gdb_syscall_complete_cb current_syscall_cb;
GString *str_buf;
GByteArray *mem_buf;
+ int sstep_flags;
+ int supported_sstep_flags;
} GDBState;
-/* By default use no IRQs and no timers while single stepping so as to
- * make single stepping like an ICE HW step.
- */
-static int sstep_flags = SSTEP_ENABLE|SSTEP_NOIRQ|SSTEP_NOTIMER;
-
-/* Retrieves flags for single step mode. */
-static int get_sstep_flags(void)
-{
- /*
- * In replay mode all events written into the log should be replayed.
- * That is why NOIRQ flag is removed in this mode.
- */
- if (replay_mode != REPLAY_MODE_NONE) {
- return SSTEP_ENABLE;
- } else {
- return sstep_flags;
- }
-}
-
static GDBState gdbserver_state;
static void init_gdbserver_state(void)
@@ -399,6 +382,26 @@ static void init_gdbserver_state(void)
gdbserver_state.str_buf = g_string_new(NULL);
gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH);
gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4);
+
+ /*
+ * In replay mode all events will come from the log and can't be
+ * suppressed otherwise we would break determinism. However as those
+ * events are tied to the number of executed instructions we won't see
+ * them occurring every time we single step.
+ */
+ if (replay_mode != REPLAY_MODE_NONE) {
+ gdbserver_state.supported_sstep_flags = SSTEP_ENABLE;
+ } else {
+ gdbserver_state.supported_sstep_flags =
+ SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
+ }
+
+ /*
+ * By default use no IRQs and no timers while single stepping so as to
+ * make single stepping like an ICE HW step.
+ */
+ gdbserver_state.sstep_flags = gdbserver_state.supported_sstep_flags;
+
}
#ifndef CONFIG_USER_ONLY
@@ -505,7 +508,7 @@ static int gdb_continue_partial(char *newstates)
CPU_FOREACH(cpu) {
if (newstates[cpu->cpu_index] == 's') {
trace_gdbstub_op_stepping(cpu->cpu_index);
- cpu_single_step(cpu, sstep_flags);
+ cpu_single_step(cpu, gdbserver_state.sstep_flags);
}
}
gdbserver_state.running_state = 1;
@@ -524,7 +527,7 @@ static int gdb_continue_partial(char *newstates)
break; /* nothing to do here */
case 's':
trace_gdbstub_op_stepping(cpu->cpu_index);
- cpu_single_step(cpu, get_sstep_flags());
+ cpu_single_step(cpu, gdbserver_state.sstep_flags);
cpu_resume(cpu);
flag = 1;
break;
@@ -1883,7 +1886,7 @@ static void handle_step(GArray *params, void *user_ctx)
gdb_set_cpu_pc((target_ulong)get_param(params, 0)->val_ull);
}
- cpu_single_step(gdbserver_state.c_cpu, get_sstep_flags());
+ cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags);
gdb_continue();
}
@@ -2017,24 +2020,44 @@ static void handle_v_commands(GArray *params, void *user_ctx)
static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx)
{
- g_string_printf(gdbserver_state.str_buf, "ENABLE=%x,NOIRQ=%x,NOTIMER=%x",
- SSTEP_ENABLE, SSTEP_NOIRQ, SSTEP_NOTIMER);
+ g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE);
+
+ if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) {
+ g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x",
+ SSTEP_NOIRQ);
+ }
+
+ if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) {
+ g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x",
+ SSTEP_NOTIMER);
+ }
+
put_strbuf();
}
static void handle_set_qemu_sstep(GArray *params, void *user_ctx)
{
+ int new_sstep_flags;
+
if (!params->len) {
return;
}
- sstep_flags = get_param(params, 0)->val_ul;
+ new_sstep_flags = get_param(params, 0)->val_ul;
+
+ if (new_sstep_flags & ~gdbserver_state.supported_sstep_flags) {
+ put_packet("E22");
+ return;
+ }
+
+ gdbserver_state.sstep_flags = new_sstep_flags;
put_packet("OK");
}
static void handle_query_qemu_sstep(GArray *params, void *user_ctx)
{
- g_string_printf(gdbserver_state.str_buf, "0x%x", sstep_flags);
+ g_string_printf(gdbserver_state.str_buf, "0x%x",
+ gdbserver_state.sstep_flags);
put_strbuf();
}