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>
This commit is contained in:
Maxim Levitsky 2021-11-11 12:06:02 +01:00 committed by Paolo Bonzini
parent 43709a0ca3
commit ecd39d620b

View File

@ -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();
}