Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
accel/kvm/kvm-all.c | 25 ++++++++++++++++++
gdbstub.c | 62 ++++++++++++++++++++++++++++++++++++--------
include/sysemu/kvm.h | 15 +++++++++++
3 files changed, 91 insertions(+), 11 deletions(-)
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 5558786d3d..a92c12da6f 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -169,6 +169,8 @@ bool kvm_vm_attributes_allowed;
bool kvm_direct_msi_allowed;
bool kvm_ioeventfd_any_length_allowed;
bool kvm_msi_use_devid;
+bool kvm_has_guest_debug;
+int kvm_sstep_flags;
static bool kvm_immediate_exit;
static hwaddr kvm_max_slot_size = ~0;
@@ -2562,6 +2564,25 @@ static int kvm_init(MachineState *ms)
kvm_sregs2 =
(kvm_check_extension(s, KVM_CAP_SREGS2) > 0);
+ kvm_has_guest_debug =
+ (kvm_check_extension(s, KVM_CAP_SET_GUEST_DEBUG) > 0);
+
+ kvm_sstep_flags = 0;
+
+ if (kvm_has_guest_debug) {
+ /* Assume that single stepping is supported */
+ kvm_sstep_flags = SSTEP_ENABLE;
+
+ int guest_debug_flags =
+ kvm_check_extension(s, KVM_CAP_SET_GUEST_DEBUG2);
+
+ if (guest_debug_flags > 0) {
+ if (guest_debug_flags & KVM_GUESTDBG_BLOCKIRQ) {
+ kvm_sstep_flags |= SSTEP_NOIRQ;
+ }
+ }
+ }
+
kvm_state = s;
ret = kvm_arch_init(ms, s);
@@ -3191,6 +3212,10 @@ int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
if (cpu->singlestep_enabled) {
data.dbg.control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
+
+ if (cpu->singlestep_enabled & SSTEP_NOIRQ) {
+ data.dbg.control |= KVM_GUESTDBG_BLOCKIRQ;
+ }
}
kvm_arch_update_guest_debug(cpu, &data.dbg);
diff --git a/gdbstub.c b/gdbstub.c
index 36b85aa50e..ad088fbd3e 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -368,12 +368,11 @@ 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;
+static GDBState gdbserver_state;
/* Retrieves flags for single step mode. */
static int get_sstep_flags(void)
@@ -385,11 +384,10 @@ static int get_sstep_flags(void)
if (replay_mode != REPLAY_MODE_NONE) {
return SSTEP_ENABLE;
} else {
- return sstep_flags;
+ return gdbserver_state.sstep_flags;
}
}
-static GDBState gdbserver_state;
static void init_gdbserver_state(void)
{
@@ -399,6 +397,23 @@ 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);
+
+
+ if (kvm_enabled()) {
+ gdbserver_state.supported_sstep_flags = kvm_get_supported_sstep_flags();
+ } 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 = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
+ gdbserver_state.sstep_flags &= gdbserver_state.supported_sstep_flags;
+
}
#ifndef CONFIG_USER_ONLY
@@ -505,7 +520,7 @@ 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, get_sstep_flags());
}
}
gdbserver_state.running_state = 1;
@@ -2017,24 +2032,44 @@ 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();
}
@@ -3493,6 +3528,11 @@ int gdbserver_start(const char *device)
return -1;
}
+ if (kvm_enabled() && !kvm_supports_guest_debug()) {
+ error_report("gdbstub: KVM doesn't support guest debugging");
+ return -1;
+ }
+
if (!device)
return -1;
if (strcmp(device, "none") != 0) {
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index b3d4538c55..2eb5b4d68d 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -47,6 +47,8 @@ extern bool kvm_readonly_mem_allowed;
extern bool kvm_direct_msi_allowed;
extern bool kvm_ioeventfd_any_length_allowed;
extern bool kvm_msi_use_devid;
+extern bool kvm_has_guest_debug;
+extern int kvm_sstep_flags;
#define kvm_enabled() (kvm_allowed)
/**
@@ -171,6 +173,17 @@ extern bool kvm_msi_use_devid;
*/
#define kvm_msi_devid_required() (kvm_msi_use_devid)
+/*
+ * Does KVM support guest debugging
+ */
+#define kvm_supports_guest_debug() (kvm_has_guest_debug)
+
+/*
+ * kvm_supported_sstep_flags
+ * Returns: SSTEP_* flags that KVM supports for guest debug
+ */
+#define kvm_get_supported_sstep_flags() (kvm_sstep_flags)
+
#else
#define kvm_enabled() (0)
@@ -188,6 +201,8 @@ extern bool kvm_msi_use_devid;
#define kvm_direct_msi_enabled() (false)
#define kvm_ioeventfd_any_length_enabled() (false)
#define kvm_msi_devid_required() (false)
+#define kvm_supports_guest_debug() (false)
+#define kvm_get_supported_sstep_flags() (0)
#endif /* CONFIG_KVM_IS_POSSIBLE */
--
2.26.3
