X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=gdbstub.c;h=8618e3431107354f5dda48298e8d19b01dad165f;hb=db68f4ff06cbe0517ed0d9b5634f6cddaed2547c;hp=02beb44d97367e4d0f320240e8985b921d780c87;hpb=1a2273369725111a2bbdb602ca7c679d466618b0;p=mirror_qemu.git

diff --git a/gdbstub.c b/gdbstub.c
index 02beb44d97..8618e34311 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -16,10 +16,14 @@
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
+
 #include "qemu/osdep.h"
+#include "qemu-common.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
+#include "qemu/ctype.h"
 #include "qemu/cutils.h"
+#include "qemu/module.h"
 #include "trace-root.h"
 #ifdef CONFIG_USER_ONLY
 #include "qemu.h"
@@ -37,7 +41,7 @@
 #include "qemu/sockets.h"
 #include "sysemu/hw_accel.h"
 #include "sysemu/kvm.h"
-#include "exec/semihost.h"
+#include "hw/semihosting/semihost.h"
 #include "exec/exec-all.h"
 
 #ifdef CONFIG_USER_ONLY
@@ -46,11 +50,27 @@
 #define GDB_ATTACHED "1"
 #endif
 
+#ifndef CONFIG_USER_ONLY
+static int phy_memory_mode;
+#endif
+
 static inline int target_memory_rw_debug(CPUState *cpu, target_ulong addr,
                                          uint8_t *buf, int len, bool is_write)
 {
-    CPUClass *cc = CPU_GET_CLASS(cpu);
+    CPUClass *cc;
+
+#ifndef CONFIG_USER_ONLY
+    if (phy_memory_mode) {
+        if (is_write) {
+            cpu_physical_memory_write(addr, buf, len);
+        } else {
+            cpu_physical_memory_read(addr, buf, len);
+        }
+        return 0;
+    }
+#endif
 
+    cc = CPU_GET_CLASS(cpu);
     if (cc->memory_rw_debug) {
         return cc->memory_rw_debug(cpu, addr, buf, len, is_write);
     }
@@ -300,6 +320,8 @@ typedef struct GDBRegisterState {
 typedef struct GDBProcess {
     uint32_t pid;
     bool attached;
+
+    char target_xml[1024];
 } GDBProcess;
 
 enum RSState {
@@ -642,59 +664,160 @@ static int memtox(char *buf, const char *mem, int len)
 
 static uint32_t gdb_get_cpu_pid(const GDBState *s, CPUState *cpu)
 {
-#ifndef CONFIG_USER_ONLY
-    gchar *path, *name = NULL;
-    Object *obj;
-    CPUClusterState *cluster;
-    uint32_t ret;
+    /* TODO: In user mode, we should use the task state PID */
+    if (cpu->cluster_index == UNASSIGNED_CLUSTER_INDEX) {
+        /* Return the default process' PID */
+        return s->processes[s->process_num - 1].pid;
+    }
+    return cpu->cluster_index + 1;
+}
 
-    path = object_get_canonical_path(OBJECT(cpu));
+static GDBProcess *gdb_get_process(const GDBState *s, uint32_t pid)
+{
+    int i;
 
-    if (path == NULL) {
-        /* Return the default process' PID */
-        ret = s->processes[s->process_num - 1].pid;
-        goto out;
+    if (!pid) {
+        /* 0 means any process, we take the first one */
+        return &s->processes[0];
     }
 
-    name = object_get_canonical_path_component(OBJECT(cpu));
-    assert(name != NULL);
+    for (i = 0; i < s->process_num; i++) {
+        if (s->processes[i].pid == pid) {
+            return &s->processes[i];
+        }
+    }
 
-    /*
-     * Retrieve the CPU parent path by removing the last '/' and the CPU name
-     * from the CPU canonical path.
-     */
-    path[strlen(path) - strlen(name) - 1] = '\0';
+    return NULL;
+}
 
-    obj = object_resolve_path_type(path, TYPE_CPU_CLUSTER, NULL);
+static GDBProcess *gdb_get_cpu_process(const GDBState *s, CPUState *cpu)
+{
+    return gdb_get_process(s, gdb_get_cpu_pid(s, cpu));
+}
 
-    if (obj == NULL) {
-        /* Return the default process' PID */
-        ret = s->processes[s->process_num - 1].pid;
-        goto out;
+static CPUState *find_cpu(uint32_t thread_id)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        if (cpu_gdb_index(cpu) == thread_id) {
+            return cpu;
+        }
     }
 
-    cluster = CPU_CLUSTER(obj);
-    ret = cluster->cluster_id + 1;
+    return NULL;
+}
+
+static CPUState *get_first_cpu_in_process(const GDBState *s,
+                                          GDBProcess *process)
+{
+    CPUState *cpu;
 
-out:
-    g_free(name);
-    g_free(path);
+    CPU_FOREACH(cpu) {
+        if (gdb_get_cpu_pid(s, cpu) == process->pid) {
+            return cpu;
+        }
+    }
 
-    return ret;
+    return NULL;
+}
 
-#else
-    /* TODO: In user mode, we should use the task state PID */
-    return s->processes[s->process_num - 1].pid;
-#endif
+static CPUState *gdb_next_cpu_in_process(const GDBState *s, CPUState *cpu)
+{
+    uint32_t pid = gdb_get_cpu_pid(s, cpu);
+    cpu = CPU_NEXT(cpu);
+
+    while (cpu) {
+        if (gdb_get_cpu_pid(s, cpu) == pid) {
+            break;
+        }
+
+        cpu = CPU_NEXT(cpu);
+    }
+
+    return cpu;
+}
+
+/* Return the cpu following @cpu, while ignoring unattached processes. */
+static CPUState *gdb_next_attached_cpu(const GDBState *s, CPUState *cpu)
+{
+    cpu = CPU_NEXT(cpu);
+
+    while (cpu) {
+        if (gdb_get_cpu_process(s, cpu)->attached) {
+            break;
+        }
+
+        cpu = CPU_NEXT(cpu);
+    }
+
+    return cpu;
+}
+
+/* Return the first attached cpu */
+static CPUState *gdb_first_attached_cpu(const GDBState *s)
+{
+    CPUState *cpu = first_cpu;
+    GDBProcess *process = gdb_get_cpu_process(s, cpu);
+
+    if (!process->attached) {
+        return gdb_next_attached_cpu(s, cpu);
+    }
+
+    return cpu;
+}
+
+static CPUState *gdb_get_cpu(const GDBState *s, uint32_t pid, uint32_t tid)
+{
+    GDBProcess *process;
+    CPUState *cpu;
+
+    if (!pid && !tid) {
+        /* 0 means any process/thread, we take the first attached one */
+        return gdb_first_attached_cpu(s);
+    } else if (pid && !tid) {
+        /* any thread in a specific process */
+        process = gdb_get_process(s, pid);
+
+        if (process == NULL) {
+            return NULL;
+        }
+
+        if (!process->attached) {
+            return NULL;
+        }
+
+        return get_first_cpu_in_process(s, process);
+    } else {
+        /* a specific thread */
+        cpu = find_cpu(tid);
+
+        if (cpu == NULL) {
+            return NULL;
+        }
+
+        process = gdb_get_cpu_process(s, cpu);
+
+        if (pid && process->pid != pid) {
+            return NULL;
+        }
+
+        if (!process->attached) {
+            return NULL;
+        }
+
+        return cpu;
+    }
 }
 
-static const char *get_feature_xml(const char *p, const char **newp,
-                                   CPUClass *cc)
+static const char *get_feature_xml(const GDBState *s, const char *p,
+                                   const char **newp, GDBProcess *process)
 {
     size_t len;
     int i;
     const char *name;
-    static char target_xml[1024];
+    CPUState *cpu = get_first_cpu_in_process(s, process);
+    CPUClass *cc = CPU_GET_CLASS(cpu);
 
     len = 0;
     while (p[len] && p[len] != ':')
@@ -703,36 +826,37 @@ static const char *get_feature_xml(const char *p, const char **newp,
 
     name = NULL;
     if (strncmp(p, "target.xml", len) == 0) {
+        char *buf = process->target_xml;
+        const size_t buf_sz = sizeof(process->target_xml);
+
         /* Generate the XML description for this CPU.  */
-        if (!target_xml[0]) {
+        if (!buf[0]) {
             GDBRegisterState *r;
-            CPUState *cpu = first_cpu;
 
-            pstrcat(target_xml, sizeof(target_xml),
+            pstrcat(buf, buf_sz,
                     "<?xml version=\"1.0\"?>"
                     "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
                     "<target>");
             if (cc->gdb_arch_name) {
                 gchar *arch = cc->gdb_arch_name(cpu);
-                pstrcat(target_xml, sizeof(target_xml), "<architecture>");
-                pstrcat(target_xml, sizeof(target_xml), arch);
-                pstrcat(target_xml, sizeof(target_xml), "</architecture>");
+                pstrcat(buf, buf_sz, "<architecture>");
+                pstrcat(buf, buf_sz, arch);
+                pstrcat(buf, buf_sz, "</architecture>");
                 g_free(arch);
             }
-            pstrcat(target_xml, sizeof(target_xml), "<xi:include href=\"");
-            pstrcat(target_xml, sizeof(target_xml), cc->gdb_core_xml_file);
-            pstrcat(target_xml, sizeof(target_xml), "\"/>");
+            pstrcat(buf, buf_sz, "<xi:include href=\"");
+            pstrcat(buf, buf_sz, cc->gdb_core_xml_file);
+            pstrcat(buf, buf_sz, "\"/>");
             for (r = cpu->gdb_regs; r; r = r->next) {
-                pstrcat(target_xml, sizeof(target_xml), "<xi:include href=\"");
-                pstrcat(target_xml, sizeof(target_xml), r->xml);
-                pstrcat(target_xml, sizeof(target_xml), "\"/>");
+                pstrcat(buf, buf_sz, "<xi:include href=\"");
+                pstrcat(buf, buf_sz, r->xml);
+                pstrcat(buf, buf_sz, "\"/>");
             }
-            pstrcat(target_xml, sizeof(target_xml), "</target>");
+            pstrcat(buf, buf_sz, "</target>");
         }
-        return target_xml;
+        return buf;
     }
     if (cc->gdb_get_dynamic_xml) {
-        CPUState *cpu = first_cpu;
         char *xmlname = g_strndup(p, len);
         const char *xml = cc->gdb_get_dynamic_xml(cpu, xmlname);
 
@@ -846,7 +970,7 @@ static inline int xlat_gdb_type(CPUState *cpu, int gdbtype)
 }
 #endif
 
-static int gdb_breakpoint_insert(target_ulong addr, target_ulong len, int type)
+static int gdb_breakpoint_insert(int type, target_ulong addr, target_ulong len)
 {
     CPUState *cpu;
     int err = 0;
@@ -883,7 +1007,7 @@ static int gdb_breakpoint_insert(target_ulong addr, target_ulong len, int type)
     }
 }
 
-static int gdb_breakpoint_remove(target_ulong addr, target_ulong len, int type)
+static int gdb_breakpoint_remove(int type, target_ulong addr, target_ulong len)
 {
     CPUState *cpu;
     int err = 0;
@@ -919,6 +1043,24 @@ static int gdb_breakpoint_remove(target_ulong addr, target_ulong len, int type)
     }
 }
 
+static inline void gdb_cpu_breakpoint_remove_all(CPUState *cpu)
+{
+    cpu_breakpoint_remove_all(cpu, BP_GDB);
+#ifndef CONFIG_USER_ONLY
+    cpu_watchpoint_remove_all(cpu, BP_GDB);
+#endif
+}
+
+static void gdb_process_breakpoint_remove_all(const GDBState *s, GDBProcess *p)
+{
+    CPUState *cpu = get_first_cpu_in_process(s, p);
+
+    while (cpu) {
+        gdb_cpu_breakpoint_remove_all(cpu);
+        cpu = gdb_next_cpu_in_process(s, cpu);
+    }
+}
+
 static void gdb_breakpoint_remove_all(void)
 {
     CPUState *cpu;
@@ -929,10 +1071,7 @@ static void gdb_breakpoint_remove_all(void)
     }
 
     CPU_FOREACH(cpu) {
-        cpu_breakpoint_remove_all(cpu, BP_GDB);
-#ifndef CONFIG_USER_ONLY
-        cpu_watchpoint_remove_all(cpu, BP_GDB);
-#endif
+        gdb_cpu_breakpoint_remove_all(cpu);
     }
 }
 
@@ -944,19 +1083,6 @@ static void gdb_set_cpu_pc(GDBState *s, target_ulong pc)
     cpu_set_pc(cpu, pc);
 }
 
-static CPUState *find_cpu(uint32_t thread_id)
-{
-    CPUState *cpu;
-
-    CPU_FOREACH(cpu) {
-        if (cpu_gdb_index(cpu) == thread_id) {
-            return cpu;
-        }
-    }
-
-    return NULL;
-}
-
 static char *gdb_fmt_thread_id(const GDBState *s, CPUState *cpu,
                            char *buf, size_t buf_size)
 {
@@ -970,12 +1096,58 @@ static char *gdb_fmt_thread_id(const GDBState *s, CPUState *cpu,
     return buf;
 }
 
-static int is_query_packet(const char *p, const char *query, char separator)
+typedef enum GDBThreadIdKind {
+    GDB_ONE_THREAD = 0,
+    GDB_ALL_THREADS,     /* One process, all threads */
+    GDB_ALL_PROCESSES,
+    GDB_READ_THREAD_ERR
+} GDBThreadIdKind;
+
+static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf,
+                                      uint32_t *pid, uint32_t *tid)
 {
-    unsigned int query_len = strlen(query);
+    unsigned long p, t;
+    int ret;
+
+    if (*buf == 'p') {
+        buf++;
+        ret = qemu_strtoul(buf, &buf, 16, &p);
+
+        if (ret) {
+            return GDB_READ_THREAD_ERR;
+        }
+
+        /* Skip '.' */
+        buf++;
+    } else {
+        p = 1;
+    }
+
+    ret = qemu_strtoul(buf, &buf, 16, &t);
+
+    if (ret) {
+        return GDB_READ_THREAD_ERR;
+    }
+
+    *end_buf = buf;
+
+    if (p == -1) {
+        return GDB_ALL_PROCESSES;
+    }
+
+    if (pid) {
+        *pid = p;
+    }
+
+    if (t == -1) {
+        return GDB_ALL_THREADS;
+    }
+
+    if (tid) {
+        *tid = t;
+    }
 
-    return strncmp(p, query, query_len) == 0 &&
-        (p[query_len] == '\0' || p[query_len] == separator);
+    return GDB_ONE_THREAD;
 }
 
 /**
@@ -985,11 +1157,14 @@ static int is_query_packet(const char *p, const char *query, char separator)
  */
 static int gdb_handle_vcont(GDBState *s, const char *p)
 {
-    int res, idx, signal = 0;
+    int res, signal = 0;
     char cur_action;
     char *newstates;
     unsigned long tmp;
+    uint32_t pid, tid;
+    GDBProcess *process;
     CPUState *cpu;
+    GDBThreadIdKind kind;
 #ifdef CONFIG_USER_ONLY
     int max_cpus = 1; /* global variable max_cpus exists only in system mode */
 
@@ -1031,25 +1206,57 @@ static int gdb_handle_vcont(GDBState *s, const char *p)
             res = -ENOTSUP;
             goto out;
         }
-        /* thread specification. special values: (none), -1 = all; 0 = any */
-        if ((p[0] == ':' && p[1] == '-' && p[2] == '1') || (p[0] != ':')) {
-            if (*p == ':') {
-                p += 3;
-            }
-            for (idx = 0; idx < max_cpus; idx++) {
-                if (newstates[idx] == 1) {
-                    newstates[idx] = cur_action;
+
+        if (*p == '\0' || *p == ';') {
+            /*
+             * No thread specifier, action is on "all threads". The
+             * specification is unclear regarding the process to act on. We
+             * choose all processes.
+             */
+            kind = GDB_ALL_PROCESSES;
+        } else if (*p++ == ':') {
+            kind = read_thread_id(p, &p, &pid, &tid);
+        } else {
+            res = -ENOTSUP;
+            goto out;
+        }
+
+        switch (kind) {
+        case GDB_READ_THREAD_ERR:
+            res = -EINVAL;
+            goto out;
+
+        case GDB_ALL_PROCESSES:
+            cpu = gdb_first_attached_cpu(s);
+            while (cpu) {
+                if (newstates[cpu->cpu_index] == 1) {
+                    newstates[cpu->cpu_index] = cur_action;
                 }
+
+                cpu = gdb_next_attached_cpu(s, cpu);
             }
-        } else if (*p == ':') {
-            p++;
-            res = qemu_strtoul(p, &p, 16, &tmp);
-            if (res) {
+            break;
+
+        case GDB_ALL_THREADS:
+            process = gdb_get_process(s, pid);
+
+            if (!process->attached) {
+                res = -EINVAL;
                 goto out;
             }
 
-            /* 0 means any thread, so we pick the first valid CPU */
-            cpu = tmp ? find_cpu(tmp) : first_cpu;
+            cpu = get_first_cpu_in_process(s, process);
+            while (cpu) {
+                if (newstates[cpu->cpu_index] == 1) {
+                    newstates[cpu->cpu_index] = cur_action;
+                }
+
+                cpu = gdb_next_cpu_in_process(s, cpu);
+            }
+            break;
+
+        case GDB_ONE_THREAD:
+            cpu = gdb_get_cpu(s, pid, tid);
 
             /* invalid CPU/thread specified */
             if (!cpu) {
@@ -1061,6 +1268,7 @@ static int gdb_handle_vcont(GDBState *s, const char *p)
             if (newstates[cpu->cpu_index] == 1) {
                 newstates[cpu->cpu_index] = cur_action;
             }
+            break;
         }
     }
     s->signal = signal;
@@ -1072,416 +1280,1314 @@ out:
     return res;
 }
 
-static int gdb_handle_packet(GDBState *s, const char *line_buf)
+typedef union GdbCmdVariant {
+    const char *data;
+    uint8_t opcode;
+    unsigned long val_ul;
+    unsigned long long val_ull;
+    struct {
+        GDBThreadIdKind kind;
+        uint32_t pid;
+        uint32_t tid;
+    } thread_id;
+} GdbCmdVariant;
+
+static const char *cmd_next_param(const char *param, const char delimiter)
 {
-    CPUState *cpu;
-    CPUClass *cc;
-    const char *p;
-    uint32_t thread;
-    int ch, reg_size, type, res;
-    uint8_t mem_buf[MAX_PACKET_LENGTH];
-    char buf[sizeof(mem_buf) + 1 /* trailing NUL */];
-    char thread_id[16];
-    uint8_t *registers;
-    target_ulong addr, len;
+    static const char all_delimiters[] = ",;:=";
+    char curr_delimiters[2] = {0};
+    const char *delimiters;
+
+    if (delimiter == '?') {
+        delimiters = all_delimiters;
+    } else if (delimiter == '0') {
+        return strchr(param, '\0');
+    } else if (delimiter == '.' && *param) {
+        return param + 1;
+    } else {
+        curr_delimiters[0] = delimiter;
+        delimiters = curr_delimiters;
+    }
 
-    trace_gdbstub_io_command(line_buf);
+    param += strcspn(param, delimiters);
+    if (*param) {
+        param++;
+    }
+    return param;
+}
 
-    p = line_buf;
-    ch = *p++;
-    switch(ch) {
-    case '?':
-        /* TODO: Make this return the correct value for user-mode.  */
-        snprintf(buf, sizeof(buf), "T%02xthread:%s;", GDB_SIGNAL_TRAP,
-                 gdb_fmt_thread_id(s, s->c_cpu, thread_id, sizeof(thread_id)));
-        put_packet(s, buf);
-        /* Remove all the breakpoints when this query is issued,
-         * because gdb is doing and initial connect and the state
-         * should be cleaned up.
-         */
-        gdb_breakpoint_remove_all();
-        break;
-    case 'c':
-        if (*p != '\0') {
-            addr = strtoull(p, (char **)&p, 16);
-            gdb_set_cpu_pc(s, addr);
-        }
-        s->signal = 0;
-        gdb_continue(s);
-        return RS_IDLE;
-    case 'C':
-        s->signal = gdb_signal_to_target (strtoul(p, (char **)&p, 16));
-        if (s->signal == -1)
-            s->signal = 0;
-        gdb_continue(s);
-        return RS_IDLE;
-    case 'v':
-        if (strncmp(p, "Cont", 4) == 0) {
-            p += 4;
-            if (*p == '?') {
-                put_packet(s, "vCont;c;C;s;S");
-                break;
-            }
+static int cmd_parse_params(const char *data, const char *schema,
+                            GdbCmdVariant *params, int *num_params)
+{
+    int curr_param;
+    const char *curr_schema, *curr_data;
 
-            res = gdb_handle_vcont(s, p);
+    *num_params = 0;
 
-            if (res) {
-                if ((res == -EINVAL) || (res == -ERANGE)) {
-                    put_packet(s, "E22");
-                    break;
-                }
-                goto unknown_command;
+    if (!schema) {
+        return 0;
+    }
+
+    curr_schema = schema;
+    curr_param = 0;
+    curr_data = data;
+    while (curr_schema[0] && curr_schema[1] && *curr_data) {
+        switch (curr_schema[0]) {
+        case 'l':
+            if (qemu_strtoul(curr_data, &curr_data, 16,
+                             &params[curr_param].val_ul)) {
+                return -EINVAL;
             }
+            curr_param++;
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
             break;
-        } else {
-            goto unknown_command;
+        case 'L':
+            if (qemu_strtou64(curr_data, &curr_data, 16,
+                              (uint64_t *)&params[curr_param].val_ull)) {
+                return -EINVAL;
+            }
+            curr_param++;
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
+            break;
+        case 's':
+            params[curr_param].data = curr_data;
+            curr_param++;
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
+            break;
+        case 'o':
+            params[curr_param].opcode = *(uint8_t *)curr_data;
+            curr_param++;
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
+            break;
+        case 't':
+            params[curr_param].thread_id.kind =
+                read_thread_id(curr_data, &curr_data,
+                               &params[curr_param].thread_id.pid,
+                               &params[curr_param].thread_id.tid);
+            curr_param++;
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
+            break;
+        case '?':
+            curr_data = cmd_next_param(curr_data, curr_schema[1]);
+            break;
+        default:
+            return -EINVAL;
         }
-    case 'k':
-        /* Kill the target */
-        error_report("QEMU: Terminated via GDBstub");
-        exit(0);
-    case 'D':
-        /* Detach packet */
-        gdb_breakpoint_remove_all();
-        gdb_syscall_mode = GDB_SYS_DISABLED;
-        gdb_continue(s);
-        put_packet(s, "OK");
-        break;
-    case 's':
-        if (*p != '\0') {
-            addr = strtoull(p, (char **)&p, 16);
-            gdb_set_cpu_pc(s, addr);
+        curr_schema += 2;
+    }
+
+    *num_params = curr_param;
+    return 0;
+}
+
+typedef struct GdbCmdContext {
+    GDBState *s;
+    GdbCmdVariant *params;
+    int num_params;
+    uint8_t mem_buf[MAX_PACKET_LENGTH];
+    char str_buf[MAX_PACKET_LENGTH + 1];
+} GdbCmdContext;
+
+typedef void (*GdbCmdHandler)(GdbCmdContext *gdb_ctx, void *user_ctx);
+
+/*
+ * cmd_startswith -> cmd is compared using startswith
+ *
+ *
+ * schema definitions:
+ * Each schema parameter entry consists of 2 chars,
+ * the first char represents the parameter type handling
+ * the second char represents the delimiter for the next parameter
+ *
+ * Currently supported schema types:
+ * 'l' -> unsigned long (stored in .val_ul)
+ * 'L' -> unsigned long long (stored in .val_ull)
+ * 's' -> string (stored in .data)
+ * 'o' -> single char (stored in .opcode)
+ * 't' -> thread id (stored in .thread_id)
+ * '?' -> skip according to delimiter
+ *
+ * Currently supported delimiters:
+ * '?' -> Stop at any delimiter (",;:=\0")
+ * '0' -> Stop at "\0"
+ * '.' -> Skip 1 char unless reached "\0"
+ * Any other value is treated as the delimiter value itself
+ */
+typedef struct GdbCmdParseEntry {
+    GdbCmdHandler handler;
+    const char *cmd;
+    bool cmd_startswith;
+    const char *schema;
+} GdbCmdParseEntry;
+
+static inline int startswith(const char *string, const char *pattern)
+{
+  return !strncmp(string, pattern, strlen(pattern));
+}
+
+static int process_string_cmd(GDBState *s, void *user_ctx, const char *data,
+                              const GdbCmdParseEntry *cmds, int num_cmds)
+{
+    int i, schema_len, max_num_params = 0;
+    GdbCmdContext gdb_ctx;
+
+    if (!cmds) {
+        return -1;
+    }
+
+    for (i = 0; i < num_cmds; i++) {
+        const GdbCmdParseEntry *cmd = &cmds[i];
+        g_assert(cmd->handler && cmd->cmd);
+
+        if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) ||
+            (!cmd->cmd_startswith && strcmp(cmd->cmd, data))) {
+            continue;
         }
-        cpu_single_step(s->c_cpu, sstep_flags);
-        gdb_continue(s);
-        return RS_IDLE;
-    case 'F':
-        {
-            target_ulong ret;
-            target_ulong err;
 
-            ret = strtoull(p, (char **)&p, 16);
-            if (*p == ',') {
-                p++;
-                err = strtoull(p, (char **)&p, 16);
-            } else {
-                err = 0;
-            }
-            if (*p == ',')
-                p++;
-            type = *p;
-            if (s->current_syscall_cb) {
-                s->current_syscall_cb(s->c_cpu, ret, err);
-                s->current_syscall_cb = NULL;
-            }
-            if (type == 'C') {
-                put_packet(s, "T02");
-            } else {
-                gdb_continue(s);
+        if (cmd->schema) {
+            schema_len = strlen(cmd->schema);
+            if (schema_len % 2) {
+                return -2;
             }
+
+            max_num_params = schema_len / 2;
         }
-        break;
-    case 'g':
-        cpu_synchronize_state(s->g_cpu);
-        len = 0;
-        for (addr = 0; addr < s->g_cpu->gdb_num_g_regs; addr++) {
-            reg_size = gdb_read_register(s->g_cpu, mem_buf + len, addr);
-            len += reg_size;
+
+        gdb_ctx.params =
+            (GdbCmdVariant *)alloca(sizeof(*gdb_ctx.params) * max_num_params);
+        memset(gdb_ctx.params, 0, sizeof(*gdb_ctx.params) * max_num_params);
+
+        if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
+                             gdb_ctx.params, &gdb_ctx.num_params)) {
+            return -1;
+        }
+
+        gdb_ctx.s = s;
+        cmd->handler(&gdb_ctx, user_ctx);
+        return 0;
+    }
+
+    return -1;
+}
+
+static void run_cmd_parser(GDBState *s, const char *data,
+                           const GdbCmdParseEntry *cmd)
+{
+    if (!data) {
+        return;
+    }
+
+    /* In case there was an error during the command parsing we must
+    * send a NULL packet to indicate the command is not supported */
+    if (process_string_cmd(s, NULL, data, cmd, 1)) {
+        put_packet(s, "");
+    }
+}
+
+static void handle_detach(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    GDBProcess *process;
+    GDBState *s = gdb_ctx->s;
+    uint32_t pid = 1;
+
+    if (s->multiprocess) {
+        if (!gdb_ctx->num_params) {
+            put_packet(s, "E22");
+            return;
+        }
+
+        pid = gdb_ctx->params[0].val_ul;
+    }
+
+    process = gdb_get_process(s, pid);
+    gdb_process_breakpoint_remove_all(s, process);
+    process->attached = false;
+
+    if (pid == gdb_get_cpu_pid(s, s->c_cpu)) {
+        s->c_cpu = gdb_first_attached_cpu(s);
+    }
+
+    if (pid == gdb_get_cpu_pid(s, s->g_cpu)) {
+        s->g_cpu = gdb_first_attached_cpu(s);
+    }
+
+    if (!s->c_cpu) {
+        /* No more process attached */
+        gdb_syscall_mode = GDB_SYS_DISABLED;
+        gdb_continue(s);
+    }
+    put_packet(s, "OK");
+}
+
+static void handle_thread_alive(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUState *cpu;
+
+    if (!gdb_ctx->num_params) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (gdb_ctx->params[0].thread_id.kind == GDB_READ_THREAD_ERR) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    cpu = gdb_get_cpu(gdb_ctx->s, gdb_ctx->params[0].thread_id.pid,
+                      gdb_ctx->params[0].thread_id.tid);
+    if (!cpu) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    put_packet(gdb_ctx->s, "OK");
+}
+
+static void handle_continue(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params) {
+        gdb_set_cpu_pc(gdb_ctx->s, gdb_ctx->params[0].val_ull);
+    }
+
+    gdb_ctx->s->signal = 0;
+    gdb_continue(gdb_ctx->s);
+}
+
+static void handle_cont_with_sig(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    unsigned long signal = 0;
+
+    /*
+     * Note: C sig;[addr] is currently unsupported and we simply
+     *       omit the addr parameter
+     */
+    if (gdb_ctx->num_params) {
+        signal = gdb_ctx->params[0].val_ul;
+    }
+
+    gdb_ctx->s->signal = gdb_signal_to_target(signal);
+    if (gdb_ctx->s->signal == -1) {
+        gdb_ctx->s->signal = 0;
+    }
+    gdb_continue(gdb_ctx->s);
+}
+
+static void handle_set_thread(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUState *cpu;
+
+    if (gdb_ctx->num_params != 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (gdb_ctx->params[1].thread_id.kind == GDB_READ_THREAD_ERR) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (gdb_ctx->params[1].thread_id.kind != GDB_ONE_THREAD) {
+        put_packet(gdb_ctx->s, "OK");
+        return;
+    }
+
+    cpu = gdb_get_cpu(gdb_ctx->s, gdb_ctx->params[1].thread_id.pid,
+                      gdb_ctx->params[1].thread_id.tid);
+    if (!cpu) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    /*
+     * Note: This command is deprecated and modern gdb's will be using the
+     *       vCont command instead.
+     */
+    switch (gdb_ctx->params[0].opcode) {
+    case 'c':
+        gdb_ctx->s->c_cpu = cpu;
+        put_packet(gdb_ctx->s, "OK");
+        break;
+    case 'g':
+        gdb_ctx->s->g_cpu = cpu;
+        put_packet(gdb_ctx->s, "OK");
+        break;
+    default:
+        put_packet(gdb_ctx->s, "E22");
+        break;
+    }
+}
+
+static void handle_insert_bp(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int res;
+
+    if (gdb_ctx->num_params != 3) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    res = gdb_breakpoint_insert(gdb_ctx->params[0].val_ul,
+                                gdb_ctx->params[1].val_ull,
+                                gdb_ctx->params[2].val_ull);
+    if (res >= 0) {
+        put_packet(gdb_ctx->s, "OK");
+        return;
+    } else if (res == -ENOSYS) {
+        put_packet(gdb_ctx->s, "");
+        return;
+    }
+
+    put_packet(gdb_ctx->s, "E22");
+}
+
+static void handle_remove_bp(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int res;
+
+    if (gdb_ctx->num_params != 3) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    res = gdb_breakpoint_remove(gdb_ctx->params[0].val_ul,
+                                gdb_ctx->params[1].val_ull,
+                                gdb_ctx->params[2].val_ull);
+    if (res >= 0) {
+        put_packet(gdb_ctx->s, "OK");
+        return;
+    } else if (res == -ENOSYS) {
+        put_packet(gdb_ctx->s, "");
+        return;
+    }
+
+    put_packet(gdb_ctx->s, "E22");
+}
+
+static void handle_set_reg(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int reg_size;
+
+    if (!gdb_has_xml) {
+        put_packet(gdb_ctx->s, "E00");
+        return;
+    }
+
+    if (gdb_ctx->num_params != 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    reg_size = strlen(gdb_ctx->params[1].data) / 2;
+    hextomem(gdb_ctx->mem_buf, gdb_ctx->params[1].data, reg_size);
+    gdb_write_register(gdb_ctx->s->g_cpu, gdb_ctx->mem_buf,
+                       gdb_ctx->params[0].val_ull);
+    put_packet(gdb_ctx->s, "OK");
+}
+
+static void handle_get_reg(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int reg_size;
+
+    /*
+     * Older gdb are really dumb, and don't use 'g' if 'p' is avaialable.
+     * This works, but can be very slow.  Anything new enough to
+     * understand XML also knows how to use this properly.
+     */
+    if (!gdb_has_xml) {
+        put_packet(gdb_ctx->s, "");
+        return;
+    }
+
+    if (!gdb_ctx->num_params) {
+        put_packet(gdb_ctx->s, "E14");
+        return;
+    }
+
+    reg_size = gdb_read_register(gdb_ctx->s->g_cpu, gdb_ctx->mem_buf,
+                                 gdb_ctx->params[0].val_ull);
+    if (!reg_size) {
+        put_packet(gdb_ctx->s, "E14");
+        return;
+    }
+
+    memtohex(gdb_ctx->str_buf, gdb_ctx->mem_buf, reg_size);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_write_mem(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params != 3) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    /* hextomem() reads 2*len bytes */
+    if (gdb_ctx->params[1].val_ull > strlen(gdb_ctx->params[2].data) / 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    hextomem(gdb_ctx->mem_buf, gdb_ctx->params[2].data,
+             gdb_ctx->params[1].val_ull);
+    if (target_memory_rw_debug(gdb_ctx->s->g_cpu, gdb_ctx->params[0].val_ull,
+                               gdb_ctx->mem_buf,
+                               gdb_ctx->params[1].val_ull, true)) {
+        put_packet(gdb_ctx->s, "E14");
+        return;
+    }
+
+    put_packet(gdb_ctx->s, "OK");
+}
+
+static void handle_read_mem(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params != 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    /* memtohex() doubles the required space */
+    if (gdb_ctx->params[1].val_ull > MAX_PACKET_LENGTH / 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (target_memory_rw_debug(gdb_ctx->s->g_cpu, gdb_ctx->params[0].val_ull,
+                               gdb_ctx->mem_buf,
+                               gdb_ctx->params[1].val_ull, false)) {
+        put_packet(gdb_ctx->s, "E14");
+        return;
+    }
+
+    memtohex(gdb_ctx->str_buf, gdb_ctx->mem_buf, gdb_ctx->params[1].val_ull);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_write_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    target_ulong addr, len;
+    uint8_t *registers;
+    int reg_size;
+
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    cpu_synchronize_state(gdb_ctx->s->g_cpu);
+    registers = gdb_ctx->mem_buf;
+    len = strlen(gdb_ctx->params[0].data) / 2;
+    hextomem(registers, gdb_ctx->params[0].data, len);
+    for (addr = 0; addr < gdb_ctx->s->g_cpu->gdb_num_g_regs && len > 0;
+         addr++) {
+        reg_size = gdb_write_register(gdb_ctx->s->g_cpu, registers, addr);
+        len -= reg_size;
+        registers += reg_size;
+    }
+    put_packet(gdb_ctx->s, "OK");
+}
+
+static void handle_read_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    target_ulong addr, len;
+
+    cpu_synchronize_state(gdb_ctx->s->g_cpu);
+    len = 0;
+    for (addr = 0; addr < gdb_ctx->s->g_cpu->gdb_num_g_regs; addr++) {
+        len += gdb_read_register(gdb_ctx->s->g_cpu, gdb_ctx->mem_buf + len,
+                                 addr);
+    }
+
+    memtohex(gdb_ctx->str_buf, gdb_ctx->mem_buf, len);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_file_io(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params >= 2 && gdb_ctx->s->current_syscall_cb) {
+        target_ulong ret, err;
+
+        ret = (target_ulong)gdb_ctx->params[0].val_ull;
+        err = (target_ulong)gdb_ctx->params[1].val_ull;
+        gdb_ctx->s->current_syscall_cb(gdb_ctx->s->c_cpu, ret, err);
+        gdb_ctx->s->current_syscall_cb = NULL;
+    }
+
+    if (gdb_ctx->num_params >= 3 && gdb_ctx->params[2].opcode == (uint8_t)'C') {
+        put_packet(gdb_ctx->s, "T02");
+        return;
+    }
+
+    gdb_continue(gdb_ctx->s);
+}
+
+static void handle_step(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params) {
+        gdb_set_cpu_pc(gdb_ctx->s, (target_ulong)gdb_ctx->params[0].val_ull);
+    }
+
+    cpu_single_step(gdb_ctx->s->c_cpu, sstep_flags);
+    gdb_continue(gdb_ctx->s);
+}
+
+static void handle_v_cont_query(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    put_packet(gdb_ctx->s, "vCont;c;C;s;S");
+}
+
+static void handle_v_cont(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int res;
+
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    res = gdb_handle_vcont(gdb_ctx->s, gdb_ctx->params[0].data);
+    if ((res == -EINVAL) || (res == -ERANGE)) {
+        put_packet(gdb_ctx->s, "E22");
+    } else if (res) {
+        put_packet(gdb_ctx->s, "");
+    }
+}
+
+static void handle_v_attach(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    GDBProcess *process;
+    CPUState *cpu;
+    char thread_id[16];
+
+    pstrcpy(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "E22");
+    if (!gdb_ctx->num_params) {
+        goto cleanup;
+    }
+
+    process = gdb_get_process(gdb_ctx->s, gdb_ctx->params[0].val_ul);
+    if (!process) {
+        goto cleanup;
+    }
+
+    cpu = get_first_cpu_in_process(gdb_ctx->s, process);
+    if (!cpu) {
+        goto cleanup;
+    }
+
+    process->attached = true;
+    gdb_ctx->s->g_cpu = cpu;
+    gdb_ctx->s->c_cpu = cpu;
+
+    gdb_fmt_thread_id(gdb_ctx->s, cpu, thread_id, sizeof(thread_id));
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "T%02xthread:%s;",
+             GDB_SIGNAL_TRAP, thread_id);
+cleanup:
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_v_kill(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    /* Kill the target */
+    put_packet(gdb_ctx->s, "OK");
+    error_report("QEMU: Terminated via GDBstub");
+    exit(0);
+}
+
+static GdbCmdParseEntry gdb_v_commands_table[] = {
+    /* Order is important if has same prefix */
+    {
+        .handler = handle_v_cont_query,
+        .cmd = "Cont?",
+        .cmd_startswith = 1
+    },
+    {
+        .handler = handle_v_cont,
+        .cmd = "Cont",
+        .cmd_startswith = 1,
+        .schema = "s0"
+    },
+    {
+        .handler = handle_v_attach,
+        .cmd = "Attach;",
+        .cmd_startswith = 1,
+        .schema = "l0"
+    },
+    {
+        .handler = handle_v_kill,
+        .cmd = "Kill;",
+        .cmd_startswith = 1
+    },
+};
+
+static void handle_v_commands(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    if (process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
+                           gdb_v_commands_table,
+                           ARRAY_SIZE(gdb_v_commands_table))) {
+        put_packet(gdb_ctx->s, "");
+    }
+}
+
+static void handle_query_qemu_sstepbits(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
+             "ENABLE=%x,NOIRQ=%x,NOTIMER=%x", SSTEP_ENABLE,
+             SSTEP_NOIRQ, SSTEP_NOTIMER);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_set_qemu_sstep(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    sstep_flags = gdb_ctx->params[0].val_ul;
+    put_packet(gdb_ctx->s, "OK");
+}
+
+static void handle_query_qemu_sstep(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "0x%x", sstep_flags);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_query_curr_tid(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUState *cpu;
+    GDBProcess *process;
+    char thread_id[16];
+
+    /*
+     * "Current thread" remains vague in the spec, so always return
+     * the first thread of the current process (gdb returns the
+     * first thread).
+     */
+    process = gdb_get_cpu_process(gdb_ctx->s, gdb_ctx->s->g_cpu);
+    cpu = get_first_cpu_in_process(gdb_ctx->s, process);
+    gdb_fmt_thread_id(gdb_ctx->s, cpu, thread_id, sizeof(thread_id));
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "QC%s", thread_id);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_query_threads(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    char thread_id[16];
+
+    if (!gdb_ctx->s->query_cpu) {
+        put_packet(gdb_ctx->s, "l");
+        return;
+    }
+
+    gdb_fmt_thread_id(gdb_ctx->s, gdb_ctx->s->query_cpu, thread_id,
+                      sizeof(thread_id));
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "m%s", thread_id);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+    gdb_ctx->s->query_cpu =
+        gdb_next_attached_cpu(gdb_ctx->s, gdb_ctx->s->query_cpu);
+}
+
+static void handle_query_first_threads(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    gdb_ctx->s->query_cpu = gdb_first_attached_cpu(gdb_ctx->s);
+    handle_query_threads(gdb_ctx, user_ctx);
+}
+
+static void handle_query_thread_extra(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUState *cpu;
+    int len;
+
+    if (!gdb_ctx->num_params ||
+        gdb_ctx->params[0].thread_id.kind == GDB_READ_THREAD_ERR) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    cpu = gdb_get_cpu(gdb_ctx->s, gdb_ctx->params[0].thread_id.pid,
+                      gdb_ctx->params[0].thread_id.tid);
+    if (!cpu) {
+        return;
+    }
+
+    cpu_synchronize_state(cpu);
+
+    if (gdb_ctx->s->multiprocess && (gdb_ctx->s->process_num > 1)) {
+        /* Print the CPU model and name in multiprocess mode */
+        ObjectClass *oc = object_get_class(OBJECT(cpu));
+        const char *cpu_model = object_class_get_name(oc);
+        char *cpu_name = object_get_canonical_path_component(OBJECT(cpu));
+        len = snprintf((char *)gdb_ctx->mem_buf, sizeof(gdb_ctx->str_buf) / 2,
+                       "%s %s [%s]", cpu_model, cpu_name,
+                       cpu->halted ? "halted " : "running");
+        g_free(cpu_name);
+    } else {
+        /* memtohex() doubles the required space */
+        len = snprintf((char *)gdb_ctx->mem_buf, sizeof(gdb_ctx->str_buf) / 2,
+                        "CPU#%d [%s]", cpu->cpu_index,
+                        cpu->halted ? "halted " : "running");
+    }
+    trace_gdbstub_op_extra_info((char *)gdb_ctx->mem_buf);
+    memtohex(gdb_ctx->str_buf, gdb_ctx->mem_buf, len);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+#ifdef CONFIG_USER_ONLY
+static void handle_query_offsets(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    TaskState *ts;
+
+    ts = gdb_ctx->s->c_cpu->opaque;
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
+             "Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx
+             ";Bss=" TARGET_ABI_FMT_lx,
+             ts->info->code_offset,
+             ts->info->data_offset,
+             ts->info->data_offset);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+#else
+static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    int len;
+
+    if (!gdb_ctx->num_params) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    len = strlen(gdb_ctx->params[0].data);
+    if (len % 2) {
+        put_packet(gdb_ctx->s, "E01");
+        return;
+    }
+
+    len = len / 2;
+    hextomem(gdb_ctx->mem_buf, gdb_ctx->params[0].data, len);
+    gdb_ctx->mem_buf[len++] = 0;
+    qemu_chr_be_write(gdb_ctx->s->mon_chr, gdb_ctx->mem_buf, len);
+    put_packet(gdb_ctx->s, "OK");
+
+}
+#endif
+
+static void handle_query_supported(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUClass *cc;
+
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "PacketSize=%x",
+             MAX_PACKET_LENGTH);
+    cc = CPU_GET_CLASS(first_cpu);
+    if (cc->gdb_core_xml_file) {
+        pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
+                ";qXfer:features:read+");
+    }
+
+    if (gdb_ctx->num_params &&
+        strstr(gdb_ctx->params[0].data, "multiprocess+")) {
+        gdb_ctx->s->multiprocess = true;
+    }
+
+    pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), ";multiprocess+");
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_query_xfer_features(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    GDBProcess *process;
+    CPUClass *cc;
+    unsigned long len, total_len, addr;
+    const char *xml;
+    const char *p;
+
+    if (gdb_ctx->num_params < 3) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    process = gdb_get_cpu_process(gdb_ctx->s, gdb_ctx->s->g_cpu);
+    cc = CPU_GET_CLASS(gdb_ctx->s->g_cpu);
+    if (!cc->gdb_core_xml_file) {
+        put_packet(gdb_ctx->s, "");
+        return;
+    }
+
+    gdb_has_xml = true;
+    p = gdb_ctx->params[0].data;
+    xml = get_feature_xml(gdb_ctx->s, p, &p, process);
+    if (!xml) {
+        put_packet(gdb_ctx->s, "E00");
+        return;
+    }
+
+    addr = gdb_ctx->params[1].val_ul;
+    len = gdb_ctx->params[2].val_ul;
+    total_len = strlen(xml);
+    if (addr > total_len) {
+        put_packet(gdb_ctx->s, "E00");
+        return;
+    }
+
+    if (len > (MAX_PACKET_LENGTH - 5) / 2) {
+        len = (MAX_PACKET_LENGTH - 5) / 2;
+    }
+
+    if (len < total_len - addr) {
+        gdb_ctx->str_buf[0] = 'm';
+        len = memtox(gdb_ctx->str_buf + 1, xml + addr, len);
+    } else {
+        gdb_ctx->str_buf[0] = 'l';
+        len = memtox(gdb_ctx->str_buf + 1, xml + addr, total_len - addr);
+    }
+
+    put_packet_binary(gdb_ctx->s, gdb_ctx->str_buf, len + 1, true);
+}
+
+static void handle_query_attached(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    put_packet(gdb_ctx->s, GDB_ATTACHED);
+}
+
+static void handle_query_qemu_supported(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "sstepbits;sstep");
+#ifndef CONFIG_USER_ONLY
+    pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), ";PhyMemMode");
+#endif
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+#ifndef CONFIG_USER_ONLY
+static void handle_query_qemu_phy_mem_mode(GdbCmdContext *gdb_ctx,
+                                           void *user_ctx)
+{
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "%d", phy_memory_mode);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+}
+
+static void handle_set_qemu_phy_mem_mode(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (!gdb_ctx->num_params) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (!gdb_ctx->params[0].val_ul) {
+        phy_memory_mode = 0;
+    } else {
+        phy_memory_mode = 1;
+    }
+    put_packet(gdb_ctx->s, "OK");
+}
+#endif
+
+static GdbCmdParseEntry gdb_gen_query_set_common_table[] = {
+    /* Order is important if has same prefix */
+    {
+        .handler = handle_query_qemu_sstepbits,
+        .cmd = "qemu.sstepbits",
+    },
+    {
+        .handler = handle_query_qemu_sstep,
+        .cmd = "qemu.sstep",
+    },
+    {
+        .handler = handle_set_qemu_sstep,
+        .cmd = "qemu.sstep=",
+        .cmd_startswith = 1,
+        .schema = "l0"
+    },
+};
+
+static GdbCmdParseEntry gdb_gen_query_table[] = {
+    {
+        .handler = handle_query_curr_tid,
+        .cmd = "C",
+    },
+    {
+        .handler = handle_query_threads,
+        .cmd = "sThreadInfo",
+    },
+    {
+        .handler = handle_query_first_threads,
+        .cmd = "fThreadInfo",
+    },
+    {
+        .handler = handle_query_thread_extra,
+        .cmd = "ThreadExtraInfo,",
+        .cmd_startswith = 1,
+        .schema = "t0"
+    },
+#ifdef CONFIG_USER_ONLY
+    {
+        .handler = handle_query_offsets,
+        .cmd = "Offsets",
+    },
+#else
+    {
+        .handler = handle_query_rcmd,
+        .cmd = "Rcmd,",
+        .cmd_startswith = 1,
+        .schema = "s0"
+    },
+#endif
+    {
+        .handler = handle_query_supported,
+        .cmd = "Supported:",
+        .cmd_startswith = 1,
+        .schema = "s0"
+    },
+    {
+        .handler = handle_query_supported,
+        .cmd = "Supported",
+        .schema = "s0"
+    },
+    {
+        .handler = handle_query_xfer_features,
+        .cmd = "Xfer:features:read:",
+        .cmd_startswith = 1,
+        .schema = "s:l,l0"
+    },
+    {
+        .handler = handle_query_attached,
+        .cmd = "Attached:",
+        .cmd_startswith = 1
+    },
+    {
+        .handler = handle_query_attached,
+        .cmd = "Attached",
+    },
+    {
+        .handler = handle_query_qemu_supported,
+        .cmd = "qemu.Supported",
+    },
+#ifndef CONFIG_USER_ONLY
+    {
+        .handler = handle_query_qemu_phy_mem_mode,
+        .cmd = "qemu.PhyMemMode",
+    },
+#endif
+};
+
+static GdbCmdParseEntry gdb_gen_set_table[] = {
+    /* Order is important if has same prefix */
+    {
+        .handler = handle_set_qemu_sstep,
+        .cmd = "qemu.sstep:",
+        .cmd_startswith = 1,
+        .schema = "l0"
+    },
+#ifndef CONFIG_USER_ONLY
+    {
+        .handler = handle_set_qemu_phy_mem_mode,
+        .cmd = "qemu.PhyMemMode:",
+        .cmd_startswith = 1,
+        .schema = "l0"
+    },
+#endif
+};
+
+static void handle_gen_query(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    if (!process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
+                            gdb_gen_query_set_common_table,
+                            ARRAY_SIZE(gdb_gen_query_set_common_table))) {
+        return;
+    }
+
+    if (process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
+                           gdb_gen_query_table,
+                           ARRAY_SIZE(gdb_gen_query_table))) {
+        put_packet(gdb_ctx->s, "");
+    }
+}
+
+static void handle_gen_set(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (!gdb_ctx->num_params) {
+        return;
+    }
+
+    if (!process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
+                            gdb_gen_query_set_common_table,
+                            ARRAY_SIZE(gdb_gen_query_set_common_table))) {
+        return;
+    }
+
+    if (process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
+                           gdb_gen_set_table,
+                           ARRAY_SIZE(gdb_gen_set_table))) {
+        put_packet(gdb_ctx->s, "");
+    }
+}
+
+static void handle_target_halt(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    char thread_id[16];
+
+    gdb_fmt_thread_id(gdb_ctx->s, gdb_ctx->s->c_cpu, thread_id,
+                      sizeof(thread_id));
+    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "T%02xthread:%s;",
+             GDB_SIGNAL_TRAP, thread_id);
+    put_packet(gdb_ctx->s, gdb_ctx->str_buf);
+    /*
+     * Remove all the breakpoints when this query is issued,
+     * because gdb is doing an initial connect and the state
+     * should be cleaned up.
+     */
+    gdb_breakpoint_remove_all();
+}
+
+static int gdb_handle_packet(GDBState *s, const char *line_buf)
+{
+    const GdbCmdParseEntry *cmd_parser = NULL;
+
+    trace_gdbstub_io_command(line_buf);
+
+    switch (line_buf[0]) {
+    case '!':
+        put_packet(s, "OK");
+        break;
+    case '?':
+        {
+            static const GdbCmdParseEntry target_halted_cmd_desc = {
+                .handler = handle_target_halt,
+                .cmd = "?",
+                .cmd_startswith = 1
+            };
+            cmd_parser = &target_halted_cmd_desc;
+        }
+        break;
+    case 'c':
+        {
+            static const GdbCmdParseEntry continue_cmd_desc = {
+                .handler = handle_continue,
+                .cmd = "c",
+                .cmd_startswith = 1,
+                .schema = "L0"
+            };
+            cmd_parser = &continue_cmd_desc;
+        }
+        break;
+    case 'C':
+        {
+            static const GdbCmdParseEntry cont_with_sig_cmd_desc = {
+                .handler = handle_cont_with_sig,
+                .cmd = "C",
+                .cmd_startswith = 1,
+                .schema = "l0"
+            };
+            cmd_parser = &cont_with_sig_cmd_desc;
+        }
+        break;
+    case 'v':
+        {
+            static const GdbCmdParseEntry v_cmd_desc = {
+                .handler = handle_v_commands,
+                .cmd = "v",
+                .cmd_startswith = 1,
+                .schema = "s0"
+            };
+            cmd_parser = &v_cmd_desc;
+        }
+        break;
+    case 'k':
+        /* Kill the target */
+        error_report("QEMU: Terminated via GDBstub");
+        exit(0);
+    case 'D':
+        {
+            static const GdbCmdParseEntry detach_cmd_desc = {
+                .handler = handle_detach,
+                .cmd = "D",
+                .cmd_startswith = 1,
+                .schema = "?.l0"
+            };
+            cmd_parser = &detach_cmd_desc;
+        }
+        break;
+    case 's':
+        {
+            static const GdbCmdParseEntry step_cmd_desc = {
+                .handler = handle_step,
+                .cmd = "s",
+                .cmd_startswith = 1,
+                .schema = "L0"
+            };
+            cmd_parser = &step_cmd_desc;
+        }
+        break;
+    case 'F':
+        {
+            static const GdbCmdParseEntry file_io_cmd_desc = {
+                .handler = handle_file_io,
+                .cmd = "F",
+                .cmd_startswith = 1,
+                .schema = "L,L,o0"
+            };
+            cmd_parser = &file_io_cmd_desc;
+        }
+        break;
+    case 'g':
+        {
+            static const GdbCmdParseEntry read_all_regs_cmd_desc = {
+                .handler = handle_read_all_regs,
+                .cmd = "g",
+                .cmd_startswith = 1
+            };
+            cmd_parser = &read_all_regs_cmd_desc;
         }
-        memtohex(buf, mem_buf, len);
-        put_packet(s, buf);
         break;
     case 'G':
-        cpu_synchronize_state(s->g_cpu);
-        registers = mem_buf;
-        len = strlen(p) / 2;
-        hextomem((uint8_t *)registers, p, len);
-        for (addr = 0; addr < s->g_cpu->gdb_num_g_regs && len > 0; addr++) {
-            reg_size = gdb_write_register(s->g_cpu, registers, addr);
-            len -= reg_size;
-            registers += reg_size;
+        {
+            static const GdbCmdParseEntry write_all_regs_cmd_desc = {
+                .handler = handle_write_all_regs,
+                .cmd = "G",
+                .cmd_startswith = 1,
+                .schema = "s0"
+            };
+            cmd_parser = &write_all_regs_cmd_desc;
         }
-        put_packet(s, "OK");
         break;
     case 'm':
-        addr = strtoull(p, (char **)&p, 16);
-        if (*p == ',')
-            p++;
-        len = strtoull(p, NULL, 16);
-
-        /* memtohex() doubles the required space */
-        if (len > MAX_PACKET_LENGTH / 2) {
-            put_packet (s, "E22");
-            break;
-        }
-
-        if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len, false) != 0) {
-            put_packet (s, "E14");
-        } else {
-            memtohex(buf, mem_buf, len);
-            put_packet(s, buf);
+        {
+            static const GdbCmdParseEntry read_mem_cmd_desc = {
+                .handler = handle_read_mem,
+                .cmd = "m",
+                .cmd_startswith = 1,
+                .schema = "L,L0"
+            };
+            cmd_parser = &read_mem_cmd_desc;
         }
         break;
     case 'M':
-        addr = strtoull(p, (char **)&p, 16);
-        if (*p == ',')
-            p++;
-        len = strtoull(p, (char **)&p, 16);
-        if (*p == ':')
-            p++;
-
-        /* hextomem() reads 2*len bytes */
-        if (len > strlen(p) / 2) {
-            put_packet (s, "E22");
-            break;
-        }
-        hextomem(mem_buf, p, len);
-        if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len,
-                                   true) != 0) {
-            put_packet(s, "E14");
-        } else {
-            put_packet(s, "OK");
+        {
+            static const GdbCmdParseEntry write_mem_cmd_desc = {
+                .handler = handle_write_mem,
+                .cmd = "M",
+                .cmd_startswith = 1,
+                .schema = "L,L:s0"
+            };
+            cmd_parser = &write_mem_cmd_desc;
         }
         break;
     case 'p':
-        /* Older gdb are really dumb, and don't use 'g' if 'p' is avaialable.
-           This works, but can be very slow.  Anything new enough to
-           understand XML also knows how to use this properly.  */
-        if (!gdb_has_xml)
-            goto unknown_command;
-        addr = strtoull(p, (char **)&p, 16);
-        reg_size = gdb_read_register(s->g_cpu, mem_buf, addr);
-        if (reg_size) {
-            memtohex(buf, mem_buf, reg_size);
-            put_packet(s, buf);
-        } else {
-            put_packet(s, "E14");
+        {
+            static const GdbCmdParseEntry get_reg_cmd_desc = {
+                .handler = handle_get_reg,
+                .cmd = "p",
+                .cmd_startswith = 1,
+                .schema = "L0"
+            };
+            cmd_parser = &get_reg_cmd_desc;
         }
         break;
     case 'P':
-        if (!gdb_has_xml)
-            goto unknown_command;
-        addr = strtoull(p, (char **)&p, 16);
-        if (*p == '=')
-            p++;
-        reg_size = strlen(p) / 2;
-        hextomem(mem_buf, p, reg_size);
-        gdb_write_register(s->g_cpu, mem_buf, addr);
-        put_packet(s, "OK");
+        {
+            static const GdbCmdParseEntry set_reg_cmd_desc = {
+                .handler = handle_set_reg,
+                .cmd = "P",
+                .cmd_startswith = 1,
+                .schema = "L?s0"
+            };
+            cmd_parser = &set_reg_cmd_desc;
+        }
         break;
     case 'Z':
+        {
+            static const GdbCmdParseEntry insert_bp_cmd_desc = {
+                .handler = handle_insert_bp,
+                .cmd = "Z",
+                .cmd_startswith = 1,
+                .schema = "l?L?L0"
+            };
+            cmd_parser = &insert_bp_cmd_desc;
+        }
+        break;
     case 'z':
-        type = strtoul(p, (char **)&p, 16);
-        if (*p == ',')
-            p++;
-        addr = strtoull(p, (char **)&p, 16);
-        if (*p == ',')
-            p++;
-        len = strtoull(p, (char **)&p, 16);
-        if (ch == 'Z')
-            res = gdb_breakpoint_insert(addr, len, type);
-        else
-            res = gdb_breakpoint_remove(addr, len, type);
-        if (res >= 0)
-             put_packet(s, "OK");
-        else if (res == -ENOSYS)
-            put_packet(s, "");
-        else
-            put_packet(s, "E22");
+        {
+            static const GdbCmdParseEntry remove_bp_cmd_desc = {
+                .handler = handle_remove_bp,
+                .cmd = "z",
+                .cmd_startswith = 1,
+                .schema = "l?L?L0"
+            };
+            cmd_parser = &remove_bp_cmd_desc;
+        }
         break;
     case 'H':
-        type = *p++;
-        thread = strtoull(p, (char **)&p, 16);
-        if (thread == -1 || thread == 0) {
-            put_packet(s, "OK");
-            break;
-        }
-        cpu = find_cpu(thread);
-        if (cpu == NULL) {
-            put_packet(s, "E22");
-            break;
-        }
-        switch (type) {
-        case 'c':
-            s->c_cpu = cpu;
-            put_packet(s, "OK");
-            break;
-        case 'g':
-            s->g_cpu = cpu;
-            put_packet(s, "OK");
-            break;
-        default:
-             put_packet(s, "E22");
-             break;
+        {
+            static const GdbCmdParseEntry set_thread_cmd_desc = {
+                .handler = handle_set_thread,
+                .cmd = "H",
+                .cmd_startswith = 1,
+                .schema = "o.t0"
+            };
+            cmd_parser = &set_thread_cmd_desc;
         }
         break;
     case 'T':
-        thread = strtoull(p, (char **)&p, 16);
-        cpu = find_cpu(thread);
-
-        if (cpu != NULL) {
-            put_packet(s, "OK");
-        } else {
-            put_packet(s, "E22");
+        {
+            static const GdbCmdParseEntry thread_alive_cmd_desc = {
+                .handler = handle_thread_alive,
+                .cmd = "T",
+                .cmd_startswith = 1,
+                .schema = "t0"
+            };
+            cmd_parser = &thread_alive_cmd_desc;
         }
         break;
     case 'q':
-    case 'Q':
-        /* parse any 'q' packets here */
-        if (!strcmp(p,"qemu.sstepbits")) {
-            /* Query Breakpoint bit definitions */
-            snprintf(buf, sizeof(buf), "ENABLE=%x,NOIRQ=%x,NOTIMER=%x",
-                     SSTEP_ENABLE,
-                     SSTEP_NOIRQ,
-                     SSTEP_NOTIMER);
-            put_packet(s, buf);
-            break;
-        } else if (is_query_packet(p, "qemu.sstep", '=')) {
-            /* Display or change the sstep_flags */
-            p += 10;
-            if (*p != '=') {
-                /* Display current setting */
-                snprintf(buf, sizeof(buf), "0x%x", sstep_flags);
-                put_packet(s, buf);
-                break;
-            }
-            p++;
-            type = strtoul(p, (char **)&p, 16);
-            sstep_flags = type;
-            put_packet(s, "OK");
-            break;
-        } else if (strcmp(p,"C") == 0) {
-            /* "Current thread" remains vague in the spec, so always return
-             *  the first CPU (gdb returns the first thread). */
-            put_packet(s, "QC1");
-            break;
-        } else if (strcmp(p,"fThreadInfo") == 0) {
-            s->query_cpu = first_cpu;
-            goto report_cpuinfo;
-        } else if (strcmp(p,"sThreadInfo") == 0) {
-        report_cpuinfo:
-            if (s->query_cpu) {
-                snprintf(buf, sizeof(buf), "m%x", cpu_gdb_index(s->query_cpu));
-                put_packet(s, buf);
-                s->query_cpu = CPU_NEXT(s->query_cpu);
-            } else
-                put_packet(s, "l");
-            break;
-        } else if (strncmp(p,"ThreadExtraInfo,", 16) == 0) {
-            thread = strtoull(p+16, (char **)&p, 16);
-            cpu = find_cpu(thread);
-            if (cpu != NULL) {
-                cpu_synchronize_state(cpu);
-                /* memtohex() doubles the required space */
-                len = snprintf((char *)mem_buf, sizeof(buf) / 2,
-                               "CPU#%d [%s]", cpu->cpu_index,
-                               cpu->halted ? "halted " : "running");
-                trace_gdbstub_op_extra_info((char *)mem_buf);
-                memtohex(buf, mem_buf, len);
-                put_packet(s, buf);
-            }
-            break;
-        }
-#ifdef CONFIG_USER_ONLY
-        else if (strcmp(p, "Offsets") == 0) {
-            TaskState *ts = s->c_cpu->opaque;
-
-            snprintf(buf, sizeof(buf),
-                     "Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx
-                     ";Bss=" TARGET_ABI_FMT_lx,
-                     ts->info->code_offset,
-                     ts->info->data_offset,
-                     ts->info->data_offset);
-            put_packet(s, buf);
-            break;
-        }
-#else /* !CONFIG_USER_ONLY */
-        else if (strncmp(p, "Rcmd,", 5) == 0) {
-            int len = strlen(p + 5);
-
-            if ((len % 2) != 0) {
-                put_packet(s, "E01");
-                break;
-            }
-            len = len / 2;
-            hextomem(mem_buf, p + 5, len);
-            mem_buf[len++] = 0;
-            qemu_chr_be_write(s->mon_chr, mem_buf, len);
-            put_packet(s, "OK");
-            break;
-        }
-#endif /* !CONFIG_USER_ONLY */
-        if (is_query_packet(p, "Supported", ':')) {
-            snprintf(buf, sizeof(buf), "PacketSize=%x", MAX_PACKET_LENGTH);
-            cc = CPU_GET_CLASS(first_cpu);
-            if (cc->gdb_core_xml_file != NULL) {
-                pstrcat(buf, sizeof(buf), ";qXfer:features:read+");
-            }
-            put_packet(s, buf);
-            break;
-        }
-        if (strncmp(p, "Xfer:features:read:", 19) == 0) {
-            const char *xml;
-            target_ulong total_len;
-
-            cc = CPU_GET_CLASS(first_cpu);
-            if (cc->gdb_core_xml_file == NULL) {
-                goto unknown_command;
-            }
-
-            gdb_has_xml = true;
-            p += 19;
-            xml = get_feature_xml(p, &p, cc);
-            if (!xml) {
-                snprintf(buf, sizeof(buf), "E00");
-                put_packet(s, buf);
-                break;
-            }
-
-            if (*p == ':')
-                p++;
-            addr = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            len = strtoul(p, (char **)&p, 16);
-
-            total_len = strlen(xml);
-            if (addr > total_len) {
-                snprintf(buf, sizeof(buf), "E00");
-                put_packet(s, buf);
-                break;
-            }
-            if (len > (MAX_PACKET_LENGTH - 5) / 2)
-                len = (MAX_PACKET_LENGTH - 5) / 2;
-            if (len < total_len - addr) {
-                buf[0] = 'm';
-                len = memtox(buf + 1, xml + addr, len);
-            } else {
-                buf[0] = 'l';
-                len = memtox(buf + 1, xml + addr, total_len - addr);
-            }
-            put_packet_binary(s, buf, len + 1, true);
-            break;
+        {
+            static const GdbCmdParseEntry gen_query_cmd_desc = {
+                .handler = handle_gen_query,
+                .cmd = "q",
+                .cmd_startswith = 1,
+                .schema = "s0"
+            };
+            cmd_parser = &gen_query_cmd_desc;
         }
-        if (is_query_packet(p, "Attached", ':')) {
-            put_packet(s, GDB_ATTACHED);
-            break;
+        break;
+    case 'Q':
+        {
+            static const GdbCmdParseEntry gen_set_cmd_desc = {
+                .handler = handle_gen_set,
+                .cmd = "Q",
+                .cmd_startswith = 1,
+                .schema = "s0"
+            };
+            cmd_parser = &gen_set_cmd_desc;
         }
-        /* Unrecognised 'q' command.  */
-        goto unknown_command;
-
+        break;
     default:
-    unknown_command:
         /* put empty packet */
-        buf[0] = '\0';
-        put_packet(s, buf);
+        put_packet(s, "");
         break;
     }
+
+    run_cmd_parser(s, line_buf, cmd_parser);
+
     return RS_IDLE;
 }
 
 void gdb_set_stop_cpu(CPUState *cpu)
 {
+    GDBProcess *p = gdb_get_cpu_process(gdbserver_state, cpu);
+
+    if (!p->attached) {
+        /*
+         * Having a stop CPU corresponding to a process that is not attached
+         * confuses GDB. So we ignore the request.
+         */
+        return;
+    }
+
     gdbserver_state->c_cpu = cpu;
     gdbserver_state->g_cpu = cpu;
 }
@@ -1492,6 +2598,7 @@ static void gdb_vm_state_change(void *opaque, int running, RunState state)
     GDBState *s = gdbserver_state;
     CPUState *cpu = s->c_cpu;
     char buf[256];
+    char thread_id[16];
     const char *type;
     int ret;
 
@@ -1503,6 +2610,14 @@ static void gdb_vm_state_change(void *opaque, int running, RunState state)
         put_packet(s, s->syscall_buf);
         return;
     }
+
+    if (cpu == NULL) {
+        /* No process attached */
+        return;
+    }
+
+    gdb_fmt_thread_id(s, cpu, thread_id, sizeof(thread_id));
+
     switch (state) {
     case RUN_STATE_DEBUG:
         if (cpu->watchpoint_hit) {
@@ -1520,8 +2635,8 @@ static void gdb_vm_state_change(void *opaque, int running, RunState state)
             trace_gdbstub_hit_watchpoint(type, cpu_gdb_index(cpu),
                     (target_ulong)cpu->watchpoint_hit->vaddr);
             snprintf(buf, sizeof(buf),
-                     "T%02xthread:%02x;%swatch:" TARGET_FMT_lx ";",
-                     GDB_SIGNAL_TRAP, cpu_gdb_index(cpu), type,
+                     "T%02xthread:%s;%swatch:" TARGET_FMT_lx ";",
+                     GDB_SIGNAL_TRAP, thread_id, type,
                      (target_ulong)cpu->watchpoint_hit->vaddr);
             cpu->watchpoint_hit = NULL;
             goto send_packet;
@@ -1563,7 +2678,7 @@ static void gdb_vm_state_change(void *opaque, int running, RunState state)
         break;
     }
     gdb_set_stop_cpu(cpu);
-    snprintf(buf, sizeof(buf), "T%02xthread:%02x;", ret, cpu_gdb_index(cpu));
+    snprintf(buf, sizeof(buf), "T%02xthread:%s;", ret, thread_id);
 
 send_packet:
     put_packet(s, buf);
@@ -1655,7 +2770,7 @@ void gdb_do_syscall(gdb_syscall_complete_cb cb, const char *fmt, ...)
     va_end(va);
 }
 
-static void gdb_read_byte(GDBState *s, int ch)
+static void gdb_read_byte(GDBState *s, uint8_t ch)
 {
     uint8_t reply;
 
@@ -1669,7 +2784,7 @@ static void gdb_read_byte(GDBState *s, int ch)
         } else if (ch == '+') {
             trace_gdbstub_io_got_ack();
         } else {
-            trace_gdbstub_io_got_unexpected((uint8_t)ch);
+            trace_gdbstub_io_got_unexpected(ch);
         }
 
         if (ch == '+' || ch == '$')
@@ -1692,7 +2807,7 @@ static void gdb_read_byte(GDBState *s, int ch)
                 s->line_sum = 0;
                 s->state = RS_GETLINE;
             } else {
-                trace_gdbstub_err_garbage((uint8_t)ch);
+                trace_gdbstub_err_garbage(ch);
             }
             break;
         case RS_GETLINE:
@@ -1732,13 +2847,17 @@ static void gdb_read_byte(GDBState *s, int ch)
             }
             break;
         case RS_GETLINE_RLE:
-            if (ch < ' ') {
+            /*
+             * Run-length encoding is explained in "Debugging with GDB /
+             * Appendix E GDB Remote Serial Protocol / Overview".
+             */
+            if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) {
                 /* invalid RLE count encoding */
-                trace_gdbstub_err_invalid_repeat((uint8_t)ch);
+                trace_gdbstub_err_invalid_repeat(ch);
                 s->state = RS_GETLINE;
             } else {
                 /* decode repeat length */
-                int repeat = (unsigned char)ch - ' ' + 3;
+                int repeat = ch - ' ' + 3;
                 if (s->line_buf_index + repeat >= sizeof(s->line_buf) - 1) {
                     /* that many repeats would overrun the command buffer */
                     trace_gdbstub_err_overrun();
@@ -1760,7 +2879,7 @@ static void gdb_read_byte(GDBState *s, int ch)
         case RS_CHKSUM1:
             /* get high hex digit of checksum */
             if (!isxdigit(ch)) {
-                trace_gdbstub_err_checksum_invalid((uint8_t)ch);
+                trace_gdbstub_err_checksum_invalid(ch);
                 s->state = RS_GETLINE;
                 break;
             }
@@ -1771,7 +2890,7 @@ static void gdb_read_byte(GDBState *s, int ch)
         case RS_CHKSUM2:
             /* get low hex digit of checksum */
             if (!isxdigit(ch)) {
-                trace_gdbstub_err_checksum_invalid((uint8_t)ch);
+                trace_gdbstub_err_checksum_invalid(ch);
                 s->state = RS_GETLINE;
                 break;
             }
@@ -1844,6 +2963,7 @@ static void create_default_process(GDBState *s)
 
     process->pid = max_pid + 1;
     process->attached = false;
+    process->target_xml[0] = '\0';
 }
 
 #ifdef CONFIG_USER_ONLY
@@ -1941,9 +3061,10 @@ static bool gdb_accept(void)
     }
 
     s = g_malloc0(sizeof(GDBState));
-    s->c_cpu = first_cpu;
-    s->g_cpu = first_cpu;
     create_default_process(s);
+    s->processes[0].attached = true;
+    s->c_cpu = gdb_first_attached_cpu(s);
+    s->g_cpu = s->c_cpu;
     s->fd = fd;
     gdb_has_xml = false;
 
@@ -2029,8 +3150,19 @@ static void gdb_chr_receive(void *opaque, const uint8_t *buf, int size)
 
 static void gdb_chr_event(void *opaque, int event)
 {
+    int i;
+    GDBState *s = (GDBState *) opaque;
+
     switch (event) {
     case CHR_EVENT_OPENED:
+        /* Start with first process attached, others detached */
+        for (i = 0; i < s->process_num; i++) {
+            s->processes[i].attached = !i;
+        }
+
+        s->c_cpu = gdb_first_attached_cpu(s);
+        s->g_cpu = s->c_cpu;
+
         vm_stop(RUN_STATE_PAUSED);
         gdb_has_xml = false;
         break;
@@ -2119,6 +3251,7 @@ static int find_cpu_clusters(Object *child, void *opaque)
         assert(cluster->cluster_id != UINT32_MAX);
         process->pid = cluster->cluster_id + 1;
         process->attached = false;
+        process->target_xml[0] = '\0';
 
         return 0;
     }
@@ -2196,7 +3329,7 @@ int gdbserver_start(const char *device)
          * FIXME: it's a bit weird to allow using a mux chardev here
          * and implicitly setup a monitor. We may want to break this.
          */
-        chr = qemu_chr_new_noreplay("gdb", device, true);
+        chr = qemu_chr_new_noreplay("gdb", device, true, NULL);
         if (!chr)
             return -1;
     }
@@ -2210,8 +3343,8 @@ int gdbserver_start(const char *device)
 
         /* Initialize a monitor terminal for gdb */
         mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
-                                   NULL, &error_abort);
-        monitor_init(mon_chr, 0);
+                                   NULL, NULL, &error_abort);
+        monitor_init_hmp(mon_chr, false);
     } else {
         qemu_chr_fe_deinit(&s->chr, true);
         mon_chr = s->mon_chr;
@@ -2219,15 +3352,13 @@ int gdbserver_start(const char *device)
         memset(s, 0, sizeof(GDBState));
         s->mon_chr = mon_chr;
     }
-    s->c_cpu = first_cpu;
-    s->g_cpu = first_cpu;
 
     create_processes(s);
 
     if (chr) {
         qemu_chr_fe_init(&s->chr, chr, &error_abort);
         qemu_chr_fe_set_handlers(&s->chr, gdb_chr_can_receive, gdb_chr_receive,
-                                 gdb_chr_event, NULL, NULL, NULL, true);
+                                 gdb_chr_event, NULL, s, NULL, true);
     }
     s->state = chr ? RS_IDLE : RS_INACTIVE;
     s->mon_chr = mon_chr;