xref: /openbmc/qemu/gdbstub/gdbstub.c (revision 35e087de)
1 /*
2  * gdb server stub
3  *
4  * This implements a subset of the remote protocol as described in:
5  *
6  *   https://sourceware.org/gdb/onlinedocs/gdb/Remote-Protocol.html
7  *
8  * Copyright (c) 2003-2005 Fabrice Bellard
9  *
10  * This library is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2 of the License, or (at your option) any later version.
14  *
15  * This library is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
22  *
23  * SPDX-License-Identifier: LGPL-2.0+
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qemu/ctype.h"
28 #include "qemu/cutils.h"
29 #include "qemu/module.h"
30 #include "qemu/error-report.h"
31 #include "trace.h"
32 #include "exec/gdbstub.h"
33 #include "gdbstub/syscalls.h"
34 #ifdef CONFIG_USER_ONLY
35 #include "gdbstub/user.h"
36 #else
37 #include "hw/cpu/cluster.h"
38 #include "hw/boards.h"
39 #endif
40 
41 #include "sysemu/hw_accel.h"
42 #include "sysemu/runstate.h"
43 #include "exec/replay-core.h"
44 #include "exec/hwaddr.h"
45 
46 #include "internals.h"
47 
48 typedef struct GDBRegisterState {
49     int base_reg;
50     int num_regs;
51     gdb_get_reg_cb get_reg;
52     gdb_set_reg_cb set_reg;
53     const char *xml;
54     struct GDBRegisterState *next;
55 } GDBRegisterState;
56 
57 GDBState gdbserver_state;
58 
59 void gdb_init_gdbserver_state(void)
60 {
61     g_assert(!gdbserver_state.init);
62     memset(&gdbserver_state, 0, sizeof(GDBState));
63     gdbserver_state.init = true;
64     gdbserver_state.str_buf = g_string_new(NULL);
65     gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH);
66     gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4);
67 
68     /*
69      * What single-step modes are supported is accelerator dependent.
70      * By default try to use no IRQs and no timers while single
71      * stepping so as to make single stepping like a typical ICE HW step.
72      */
73     gdbserver_state.supported_sstep_flags = accel_supported_gdbstub_sstep_flags();
74     gdbserver_state.sstep_flags = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
75     gdbserver_state.sstep_flags &= gdbserver_state.supported_sstep_flags;
76 }
77 
78 /* writes 2*len+1 bytes in buf */
79 void gdb_memtohex(GString *buf, const uint8_t *mem, int len)
80 {
81     int i, c;
82     for(i = 0; i < len; i++) {
83         c = mem[i];
84         g_string_append_c(buf, tohex(c >> 4));
85         g_string_append_c(buf, tohex(c & 0xf));
86     }
87     g_string_append_c(buf, '\0');
88 }
89 
90 void gdb_hextomem(GByteArray *mem, const char *buf, int len)
91 {
92     int i;
93 
94     for(i = 0; i < len; i++) {
95         guint8 byte = fromhex(buf[0]) << 4 | fromhex(buf[1]);
96         g_byte_array_append(mem, &byte, 1);
97         buf += 2;
98     }
99 }
100 
101 static void hexdump(const char *buf, int len,
102                     void (*trace_fn)(size_t ofs, char const *text))
103 {
104     char line_buffer[3 * 16 + 4 + 16 + 1];
105 
106     size_t i;
107     for (i = 0; i < len || (i & 0xF); ++i) {
108         size_t byte_ofs = i & 15;
109 
110         if (byte_ofs == 0) {
111             memset(line_buffer, ' ', 3 * 16 + 4 + 16);
112             line_buffer[3 * 16 + 4 + 16] = 0;
113         }
114 
115         size_t col_group = (i >> 2) & 3;
116         size_t hex_col = byte_ofs * 3 + col_group;
117         size_t txt_col = 3 * 16 + 4 + byte_ofs;
118 
119         if (i < len) {
120             char value = buf[i];
121 
122             line_buffer[hex_col + 0] = tohex((value >> 4) & 0xF);
123             line_buffer[hex_col + 1] = tohex((value >> 0) & 0xF);
124             line_buffer[txt_col + 0] = (value >= ' ' && value < 127)
125                     ? value
126                     : '.';
127         }
128 
129         if (byte_ofs == 0xF)
130             trace_fn(i & -16, line_buffer);
131     }
132 }
133 
134 /* return -1 if error, 0 if OK */
135 int gdb_put_packet_binary(const char *buf, int len, bool dump)
136 {
137     int csum, i;
138     uint8_t footer[3];
139 
140     if (dump && trace_event_get_state_backends(TRACE_GDBSTUB_IO_BINARYREPLY)) {
141         hexdump(buf, len, trace_gdbstub_io_binaryreply);
142     }
143 
144     for(;;) {
145         g_byte_array_set_size(gdbserver_state.last_packet, 0);
146         g_byte_array_append(gdbserver_state.last_packet,
147                             (const uint8_t *) "$", 1);
148         g_byte_array_append(gdbserver_state.last_packet,
149                             (const uint8_t *) buf, len);
150         csum = 0;
151         for(i = 0; i < len; i++) {
152             csum += buf[i];
153         }
154         footer[0] = '#';
155         footer[1] = tohex((csum >> 4) & 0xf);
156         footer[2] = tohex((csum) & 0xf);
157         g_byte_array_append(gdbserver_state.last_packet, footer, 3);
158 
159         gdb_put_buffer(gdbserver_state.last_packet->data,
160                    gdbserver_state.last_packet->len);
161 
162         if (gdb_got_immediate_ack()) {
163             break;
164         }
165     }
166     return 0;
167 }
168 
169 /* return -1 if error, 0 if OK */
170 int gdb_put_packet(const char *buf)
171 {
172     trace_gdbstub_io_reply(buf);
173 
174     return gdb_put_packet_binary(buf, strlen(buf), false);
175 }
176 
177 void gdb_put_strbuf(void)
178 {
179     gdb_put_packet(gdbserver_state.str_buf->str);
180 }
181 
182 /* Encode data using the encoding for 'x' packets.  */
183 void gdb_memtox(GString *buf, const char *mem, int len)
184 {
185     char c;
186 
187     while (len--) {
188         c = *(mem++);
189         switch (c) {
190         case '#': case '$': case '*': case '}':
191             g_string_append_c(buf, '}');
192             g_string_append_c(buf, c ^ 0x20);
193             break;
194         default:
195             g_string_append_c(buf, c);
196             break;
197         }
198     }
199 }
200 
201 static uint32_t gdb_get_cpu_pid(CPUState *cpu)
202 {
203 #ifdef CONFIG_USER_ONLY
204     return getpid();
205 #else
206     if (cpu->cluster_index == UNASSIGNED_CLUSTER_INDEX) {
207         /* Return the default process' PID */
208         int index = gdbserver_state.process_num - 1;
209         return gdbserver_state.processes[index].pid;
210     }
211     return cpu->cluster_index + 1;
212 #endif
213 }
214 
215 GDBProcess *gdb_get_process(uint32_t pid)
216 {
217     int i;
218 
219     if (!pid) {
220         /* 0 means any process, we take the first one */
221         return &gdbserver_state.processes[0];
222     }
223 
224     for (i = 0; i < gdbserver_state.process_num; i++) {
225         if (gdbserver_state.processes[i].pid == pid) {
226             return &gdbserver_state.processes[i];
227         }
228     }
229 
230     return NULL;
231 }
232 
233 static GDBProcess *gdb_get_cpu_process(CPUState *cpu)
234 {
235     return gdb_get_process(gdb_get_cpu_pid(cpu));
236 }
237 
238 static CPUState *find_cpu(uint32_t thread_id)
239 {
240     CPUState *cpu;
241 
242     CPU_FOREACH(cpu) {
243         if (gdb_get_cpu_index(cpu) == thread_id) {
244             return cpu;
245         }
246     }
247 
248     return NULL;
249 }
250 
251 CPUState *gdb_get_first_cpu_in_process(GDBProcess *process)
252 {
253     CPUState *cpu;
254 
255     CPU_FOREACH(cpu) {
256         if (gdb_get_cpu_pid(cpu) == process->pid) {
257             return cpu;
258         }
259     }
260 
261     return NULL;
262 }
263 
264 static CPUState *gdb_next_cpu_in_process(CPUState *cpu)
265 {
266     uint32_t pid = gdb_get_cpu_pid(cpu);
267     cpu = CPU_NEXT(cpu);
268 
269     while (cpu) {
270         if (gdb_get_cpu_pid(cpu) == pid) {
271             break;
272         }
273 
274         cpu = CPU_NEXT(cpu);
275     }
276 
277     return cpu;
278 }
279 
280 /* Return the cpu following @cpu, while ignoring unattached processes. */
281 static CPUState *gdb_next_attached_cpu(CPUState *cpu)
282 {
283     cpu = CPU_NEXT(cpu);
284 
285     while (cpu) {
286         if (gdb_get_cpu_process(cpu)->attached) {
287             break;
288         }
289 
290         cpu = CPU_NEXT(cpu);
291     }
292 
293     return cpu;
294 }
295 
296 /* Return the first attached cpu */
297 CPUState *gdb_first_attached_cpu(void)
298 {
299     CPUState *cpu = first_cpu;
300     GDBProcess *process = gdb_get_cpu_process(cpu);
301 
302     if (!process->attached) {
303         return gdb_next_attached_cpu(cpu);
304     }
305 
306     return cpu;
307 }
308 
309 static CPUState *gdb_get_cpu(uint32_t pid, uint32_t tid)
310 {
311     GDBProcess *process;
312     CPUState *cpu;
313 
314     if (!pid && !tid) {
315         /* 0 means any process/thread, we take the first attached one */
316         return gdb_first_attached_cpu();
317     } else if (pid && !tid) {
318         /* any thread in a specific process */
319         process = gdb_get_process(pid);
320 
321         if (process == NULL) {
322             return NULL;
323         }
324 
325         if (!process->attached) {
326             return NULL;
327         }
328 
329         return gdb_get_first_cpu_in_process(process);
330     } else {
331         /* a specific thread */
332         cpu = find_cpu(tid);
333 
334         if (cpu == NULL) {
335             return NULL;
336         }
337 
338         process = gdb_get_cpu_process(cpu);
339 
340         if (pid && process->pid != pid) {
341             return NULL;
342         }
343 
344         if (!process->attached) {
345             return NULL;
346         }
347 
348         return cpu;
349     }
350 }
351 
352 bool gdb_has_xml(void)
353 {
354     return !!gdb_get_cpu_process(gdbserver_state.g_cpu)->target_xml;
355 }
356 
357 static const char *get_feature_xml(const char *p, const char **newp,
358                                    GDBProcess *process)
359 {
360     CPUState *cpu = gdb_get_first_cpu_in_process(process);
361     CPUClass *cc = CPU_GET_CLASS(cpu);
362     size_t len;
363 
364     /*
365      * qXfer:features:read:ANNEX:OFFSET,LENGTH'
366      *                     ^p    ^newp
367      */
368     char *term = strchr(p, ':');
369     *newp = term + 1;
370     len = term - p;
371 
372     /* Is it the main target xml? */
373     if (strncmp(p, "target.xml", len) == 0) {
374         if (!process->target_xml) {
375             GDBRegisterState *r;
376             GString *xml = g_string_new("<?xml version=\"1.0\"?>");
377 
378             g_string_append(xml,
379                             "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
380                             "<target>");
381 
382             if (cc->gdb_arch_name) {
383                 g_autofree gchar *arch = cc->gdb_arch_name(cpu);
384                 g_string_append_printf(xml,
385                                        "<architecture>%s</architecture>",
386                                        arch);
387             }
388             g_string_append(xml, "<xi:include href=\"");
389             g_string_append(xml, cc->gdb_core_xml_file);
390             g_string_append(xml, "\"/>");
391             for (r = cpu->gdb_regs; r; r = r->next) {
392                 g_string_append(xml, "<xi:include href=\"");
393                 g_string_append(xml, r->xml);
394                 g_string_append(xml, "\"/>");
395             }
396             g_string_append(xml, "</target>");
397 
398             process->target_xml = g_string_free(xml, false);
399             return process->target_xml;
400         }
401     }
402     /* Is it dynamically generated by the target? */
403     if (cc->gdb_get_dynamic_xml) {
404         g_autofree char *xmlname = g_strndup(p, len);
405         const char *xml = cc->gdb_get_dynamic_xml(cpu, xmlname);
406         if (xml) {
407             return xml;
408         }
409     }
410     /* Is it one of the encoded gdb-xml/ files? */
411     for (int i = 0; xml_builtin[i][0]; i++) {
412         const char *name = xml_builtin[i][0];
413         if ((strncmp(name, p, len) == 0) &&
414             strlen(name) == len) {
415             return xml_builtin[i][1];
416         }
417     }
418 
419     /* failed */
420     return NULL;
421 }
422 
423 static int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg)
424 {
425     CPUClass *cc = CPU_GET_CLASS(cpu);
426     CPUArchState *env = cpu->env_ptr;
427     GDBRegisterState *r;
428 
429     if (reg < cc->gdb_num_core_regs) {
430         return cc->gdb_read_register(cpu, buf, reg);
431     }
432 
433     for (r = cpu->gdb_regs; r; r = r->next) {
434         if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {
435             return r->get_reg(env, buf, reg - r->base_reg);
436         }
437     }
438     return 0;
439 }
440 
441 static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg)
442 {
443     CPUClass *cc = CPU_GET_CLASS(cpu);
444     CPUArchState *env = cpu->env_ptr;
445     GDBRegisterState *r;
446 
447     if (reg < cc->gdb_num_core_regs) {
448         return cc->gdb_write_register(cpu, mem_buf, reg);
449     }
450 
451     for (r = cpu->gdb_regs; r; r = r->next) {
452         if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {
453             return r->set_reg(env, mem_buf, reg - r->base_reg);
454         }
455     }
456     return 0;
457 }
458 
459 void gdb_register_coprocessor(CPUState *cpu,
460                               gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg,
461                               int num_regs, const char *xml, int g_pos)
462 {
463     GDBRegisterState *s;
464     GDBRegisterState **p;
465 
466     p = &cpu->gdb_regs;
467     while (*p) {
468         /* Check for duplicates.  */
469         if (strcmp((*p)->xml, xml) == 0)
470             return;
471         p = &(*p)->next;
472     }
473 
474     s = g_new0(GDBRegisterState, 1);
475     s->base_reg = cpu->gdb_num_regs;
476     s->num_regs = num_regs;
477     s->get_reg = get_reg;
478     s->set_reg = set_reg;
479     s->xml = xml;
480 
481     /* Add to end of list.  */
482     cpu->gdb_num_regs += num_regs;
483     *p = s;
484     if (g_pos) {
485         if (g_pos != s->base_reg) {
486             error_report("Error: Bad gdb register numbering for '%s', "
487                          "expected %d got %d", xml, g_pos, s->base_reg);
488         } else {
489             cpu->gdb_num_g_regs = cpu->gdb_num_regs;
490         }
491     }
492 }
493 
494 static void gdb_process_breakpoint_remove_all(GDBProcess *p)
495 {
496     CPUState *cpu = gdb_get_first_cpu_in_process(p);
497 
498     while (cpu) {
499         gdb_breakpoint_remove_all(cpu);
500         cpu = gdb_next_cpu_in_process(cpu);
501     }
502 }
503 
504 
505 static void gdb_set_cpu_pc(vaddr pc)
506 {
507     CPUState *cpu = gdbserver_state.c_cpu;
508 
509     cpu_synchronize_state(cpu);
510     cpu_set_pc(cpu, pc);
511 }
512 
513 void gdb_append_thread_id(CPUState *cpu, GString *buf)
514 {
515     if (gdbserver_state.multiprocess) {
516         g_string_append_printf(buf, "p%02x.%02x",
517                                gdb_get_cpu_pid(cpu), gdb_get_cpu_index(cpu));
518     } else {
519         g_string_append_printf(buf, "%02x", gdb_get_cpu_index(cpu));
520     }
521 }
522 
523 static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf,
524                                       uint32_t *pid, uint32_t *tid)
525 {
526     unsigned long p, t;
527     int ret;
528 
529     if (*buf == 'p') {
530         buf++;
531         ret = qemu_strtoul(buf, &buf, 16, &p);
532 
533         if (ret) {
534             return GDB_READ_THREAD_ERR;
535         }
536 
537         /* Skip '.' */
538         buf++;
539     } else {
540         p = 0;
541     }
542 
543     ret = qemu_strtoul(buf, &buf, 16, &t);
544 
545     if (ret) {
546         return GDB_READ_THREAD_ERR;
547     }
548 
549     *end_buf = buf;
550 
551     if (p == -1) {
552         return GDB_ALL_PROCESSES;
553     }
554 
555     if (pid) {
556         *pid = p;
557     }
558 
559     if (t == -1) {
560         return GDB_ALL_THREADS;
561     }
562 
563     if (tid) {
564         *tid = t;
565     }
566 
567     return GDB_ONE_THREAD;
568 }
569 
570 /**
571  * gdb_handle_vcont - Parses and handles a vCont packet.
572  * returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is
573  *         a format error, 0 on success.
574  */
575 static int gdb_handle_vcont(const char *p)
576 {
577     int res, signal = 0;
578     char cur_action;
579     unsigned long tmp;
580     uint32_t pid, tid;
581     GDBProcess *process;
582     CPUState *cpu;
583     GDBThreadIdKind kind;
584     unsigned int max_cpus = gdb_get_max_cpus();
585     /* uninitialised CPUs stay 0 */
586     g_autofree char *newstates = g_new0(char, max_cpus);
587 
588     /* mark valid CPUs with 1 */
589     CPU_FOREACH(cpu) {
590         newstates[cpu->cpu_index] = 1;
591     }
592 
593     /*
594      * res keeps track of what error we are returning, with -ENOTSUP meaning
595      * that the command is unknown or unsupported, thus returning an empty
596      * packet, while -EINVAL and -ERANGE cause an E22 packet, due to invalid,
597      *  or incorrect parameters passed.
598      */
599     res = 0;
600 
601     /*
602      * target_count and last_target keep track of how many CPUs we are going to
603      * step or resume, and a pointer to the state structure of one of them,
604      * respectivelly
605      */
606     int target_count = 0;
607     CPUState *last_target = NULL;
608 
609     while (*p) {
610         if (*p++ != ';') {
611             return -ENOTSUP;
612         }
613 
614         cur_action = *p++;
615         if (cur_action == 'C' || cur_action == 'S') {
616             cur_action = qemu_tolower(cur_action);
617             res = qemu_strtoul(p, &p, 16, &tmp);
618             if (res) {
619                 return res;
620             }
621             signal = gdb_signal_to_target(tmp);
622         } else if (cur_action != 'c' && cur_action != 's') {
623             /* unknown/invalid/unsupported command */
624             return -ENOTSUP;
625         }
626 
627         if (*p == '\0' || *p == ';') {
628             /*
629              * No thread specifier, action is on "all threads". The
630              * specification is unclear regarding the process to act on. We
631              * choose all processes.
632              */
633             kind = GDB_ALL_PROCESSES;
634         } else if (*p++ == ':') {
635             kind = read_thread_id(p, &p, &pid, &tid);
636         } else {
637             return -ENOTSUP;
638         }
639 
640         switch (kind) {
641         case GDB_READ_THREAD_ERR:
642             return -EINVAL;
643 
644         case GDB_ALL_PROCESSES:
645             cpu = gdb_first_attached_cpu();
646             while (cpu) {
647                 if (newstates[cpu->cpu_index] == 1) {
648                     newstates[cpu->cpu_index] = cur_action;
649 
650                     target_count++;
651                     last_target = cpu;
652                 }
653 
654                 cpu = gdb_next_attached_cpu(cpu);
655             }
656             break;
657 
658         case GDB_ALL_THREADS:
659             process = gdb_get_process(pid);
660 
661             if (!process->attached) {
662                 return -EINVAL;
663             }
664 
665             cpu = gdb_get_first_cpu_in_process(process);
666             while (cpu) {
667                 if (newstates[cpu->cpu_index] == 1) {
668                     newstates[cpu->cpu_index] = cur_action;
669 
670                     target_count++;
671                     last_target = cpu;
672                 }
673 
674                 cpu = gdb_next_cpu_in_process(cpu);
675             }
676             break;
677 
678         case GDB_ONE_THREAD:
679             cpu = gdb_get_cpu(pid, tid);
680 
681             /* invalid CPU/thread specified */
682             if (!cpu) {
683                 return -EINVAL;
684             }
685 
686             /* only use if no previous match occourred */
687             if (newstates[cpu->cpu_index] == 1) {
688                 newstates[cpu->cpu_index] = cur_action;
689 
690                 target_count++;
691                 last_target = cpu;
692             }
693             break;
694         }
695     }
696 
697     /*
698      * if we're about to resume a specific set of CPUs/threads, make it so that
699      * in case execution gets interrupted, we can send GDB a stop reply with a
700      * correct value. it doesn't really matter which CPU we tell GDB the signal
701      * happened in (VM pauses stop all of them anyway), so long as it is one of
702      * the ones we resumed/single stepped here.
703      */
704     if (target_count > 0) {
705         gdbserver_state.c_cpu = last_target;
706     }
707 
708     gdbserver_state.signal = signal;
709     gdb_continue_partial(newstates);
710     return res;
711 }
712 
713 static const char *cmd_next_param(const char *param, const char delimiter)
714 {
715     static const char all_delimiters[] = ",;:=";
716     char curr_delimiters[2] = {0};
717     const char *delimiters;
718 
719     if (delimiter == '?') {
720         delimiters = all_delimiters;
721     } else if (delimiter == '0') {
722         return strchr(param, '\0');
723     } else if (delimiter == '.' && *param) {
724         return param + 1;
725     } else {
726         curr_delimiters[0] = delimiter;
727         delimiters = curr_delimiters;
728     }
729 
730     param += strcspn(param, delimiters);
731     if (*param) {
732         param++;
733     }
734     return param;
735 }
736 
737 static int cmd_parse_params(const char *data, const char *schema,
738                             GArray *params)
739 {
740     const char *curr_schema, *curr_data;
741 
742     g_assert(schema);
743     g_assert(params->len == 0);
744 
745     curr_schema = schema;
746     curr_data = data;
747     while (curr_schema[0] && curr_schema[1] && *curr_data) {
748         GdbCmdVariant this_param;
749 
750         switch (curr_schema[0]) {
751         case 'l':
752             if (qemu_strtoul(curr_data, &curr_data, 16,
753                              &this_param.val_ul)) {
754                 return -EINVAL;
755             }
756             curr_data = cmd_next_param(curr_data, curr_schema[1]);
757             g_array_append_val(params, this_param);
758             break;
759         case 'L':
760             if (qemu_strtou64(curr_data, &curr_data, 16,
761                               (uint64_t *)&this_param.val_ull)) {
762                 return -EINVAL;
763             }
764             curr_data = cmd_next_param(curr_data, curr_schema[1]);
765             g_array_append_val(params, this_param);
766             break;
767         case 's':
768             this_param.data = curr_data;
769             curr_data = cmd_next_param(curr_data, curr_schema[1]);
770             g_array_append_val(params, this_param);
771             break;
772         case 'o':
773             this_param.opcode = *(uint8_t *)curr_data;
774             curr_data = cmd_next_param(curr_data, curr_schema[1]);
775             g_array_append_val(params, this_param);
776             break;
777         case 't':
778             this_param.thread_id.kind =
779                 read_thread_id(curr_data, &curr_data,
780                                &this_param.thread_id.pid,
781                                &this_param.thread_id.tid);
782             curr_data = cmd_next_param(curr_data, curr_schema[1]);
783             g_array_append_val(params, this_param);
784             break;
785         case '?':
786             curr_data = cmd_next_param(curr_data, curr_schema[1]);
787             break;
788         default:
789             return -EINVAL;
790         }
791         curr_schema += 2;
792     }
793 
794     return 0;
795 }
796 
797 typedef void (*GdbCmdHandler)(GArray *params, void *user_ctx);
798 
799 /*
800  * cmd_startswith -> cmd is compared using startswith
801  *
802  * allow_stop_reply -> true iff the gdbstub can respond to this command with a
803  *   "stop reply" packet. The list of commands that accept such response is
804  *   defined at the GDB Remote Serial Protocol documentation. see:
805  *   https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets.
806  *
807  * schema definitions:
808  * Each schema parameter entry consists of 2 chars,
809  * the first char represents the parameter type handling
810  * the second char represents the delimiter for the next parameter
811  *
812  * Currently supported schema types:
813  * 'l' -> unsigned long (stored in .val_ul)
814  * 'L' -> unsigned long long (stored in .val_ull)
815  * 's' -> string (stored in .data)
816  * 'o' -> single char (stored in .opcode)
817  * 't' -> thread id (stored in .thread_id)
818  * '?' -> skip according to delimiter
819  *
820  * Currently supported delimiters:
821  * '?' -> Stop at any delimiter (",;:=\0")
822  * '0' -> Stop at "\0"
823  * '.' -> Skip 1 char unless reached "\0"
824  * Any other value is treated as the delimiter value itself
825  */
826 typedef struct GdbCmdParseEntry {
827     GdbCmdHandler handler;
828     const char *cmd;
829     bool cmd_startswith;
830     const char *schema;
831     bool allow_stop_reply;
832 } GdbCmdParseEntry;
833 
834 static inline int startswith(const char *string, const char *pattern)
835 {
836   return !strncmp(string, pattern, strlen(pattern));
837 }
838 
839 static int process_string_cmd(const char *data,
840                               const GdbCmdParseEntry *cmds, int num_cmds)
841 {
842     int i;
843     g_autoptr(GArray) params = g_array_new(false, true, sizeof(GdbCmdVariant));
844 
845     if (!cmds) {
846         return -1;
847     }
848 
849     for (i = 0; i < num_cmds; i++) {
850         const GdbCmdParseEntry *cmd = &cmds[i];
851         g_assert(cmd->handler && cmd->cmd);
852 
853         if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) ||
854             (!cmd->cmd_startswith && strcmp(cmd->cmd, data))) {
855             continue;
856         }
857 
858         if (cmd->schema) {
859             if (cmd_parse_params(&data[strlen(cmd->cmd)],
860                                  cmd->schema, params)) {
861                 return -1;
862             }
863         }
864 
865         gdbserver_state.allow_stop_reply = cmd->allow_stop_reply;
866         cmd->handler(params, NULL);
867         return 0;
868     }
869 
870     return -1;
871 }
872 
873 static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd)
874 {
875     if (!data) {
876         return;
877     }
878 
879     g_string_set_size(gdbserver_state.str_buf, 0);
880     g_byte_array_set_size(gdbserver_state.mem_buf, 0);
881 
882     /* In case there was an error during the command parsing we must
883     * send a NULL packet to indicate the command is not supported */
884     if (process_string_cmd(data, cmd, 1)) {
885         gdb_put_packet("");
886     }
887 }
888 
889 static void handle_detach(GArray *params, void *user_ctx)
890 {
891     GDBProcess *process;
892     uint32_t pid = 1;
893 
894     if (gdbserver_state.multiprocess) {
895         if (!params->len) {
896             gdb_put_packet("E22");
897             return;
898         }
899 
900         pid = get_param(params, 0)->val_ul;
901     }
902 
903     process = gdb_get_process(pid);
904     gdb_process_breakpoint_remove_all(process);
905     process->attached = false;
906 
907     if (pid == gdb_get_cpu_pid(gdbserver_state.c_cpu)) {
908         gdbserver_state.c_cpu = gdb_first_attached_cpu();
909     }
910 
911     if (pid == gdb_get_cpu_pid(gdbserver_state.g_cpu)) {
912         gdbserver_state.g_cpu = gdb_first_attached_cpu();
913     }
914 
915     if (!gdbserver_state.c_cpu) {
916         /* No more process attached */
917         gdb_disable_syscalls();
918         gdb_continue();
919     }
920     gdb_put_packet("OK");
921 }
922 
923 static void handle_thread_alive(GArray *params, void *user_ctx)
924 {
925     CPUState *cpu;
926 
927     if (!params->len) {
928         gdb_put_packet("E22");
929         return;
930     }
931 
932     if (get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) {
933         gdb_put_packet("E22");
934         return;
935     }
936 
937     cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid,
938                       get_param(params, 0)->thread_id.tid);
939     if (!cpu) {
940         gdb_put_packet("E22");
941         return;
942     }
943 
944     gdb_put_packet("OK");
945 }
946 
947 static void handle_continue(GArray *params, void *user_ctx)
948 {
949     if (params->len) {
950         gdb_set_cpu_pc(get_param(params, 0)->val_ull);
951     }
952 
953     gdbserver_state.signal = 0;
954     gdb_continue();
955 }
956 
957 static void handle_cont_with_sig(GArray *params, void *user_ctx)
958 {
959     unsigned long signal = 0;
960 
961     /*
962      * Note: C sig;[addr] is currently unsupported and we simply
963      *       omit the addr parameter
964      */
965     if (params->len) {
966         signal = get_param(params, 0)->val_ul;
967     }
968 
969     gdbserver_state.signal = gdb_signal_to_target(signal);
970     if (gdbserver_state.signal == -1) {
971         gdbserver_state.signal = 0;
972     }
973     gdb_continue();
974 }
975 
976 static void handle_set_thread(GArray *params, void *user_ctx)
977 {
978     CPUState *cpu;
979 
980     if (params->len != 2) {
981         gdb_put_packet("E22");
982         return;
983     }
984 
985     if (get_param(params, 1)->thread_id.kind == GDB_READ_THREAD_ERR) {
986         gdb_put_packet("E22");
987         return;
988     }
989 
990     if (get_param(params, 1)->thread_id.kind != GDB_ONE_THREAD) {
991         gdb_put_packet("OK");
992         return;
993     }
994 
995     cpu = gdb_get_cpu(get_param(params, 1)->thread_id.pid,
996                       get_param(params, 1)->thread_id.tid);
997     if (!cpu) {
998         gdb_put_packet("E22");
999         return;
1000     }
1001 
1002     /*
1003      * Note: This command is deprecated and modern gdb's will be using the
1004      *       vCont command instead.
1005      */
1006     switch (get_param(params, 0)->opcode) {
1007     case 'c':
1008         gdbserver_state.c_cpu = cpu;
1009         gdb_put_packet("OK");
1010         break;
1011     case 'g':
1012         gdbserver_state.g_cpu = cpu;
1013         gdb_put_packet("OK");
1014         break;
1015     default:
1016         gdb_put_packet("E22");
1017         break;
1018     }
1019 }
1020 
1021 static void handle_insert_bp(GArray *params, void *user_ctx)
1022 {
1023     int res;
1024 
1025     if (params->len != 3) {
1026         gdb_put_packet("E22");
1027         return;
1028     }
1029 
1030     res = gdb_breakpoint_insert(gdbserver_state.c_cpu,
1031                                 get_param(params, 0)->val_ul,
1032                                 get_param(params, 1)->val_ull,
1033                                 get_param(params, 2)->val_ull);
1034     if (res >= 0) {
1035         gdb_put_packet("OK");
1036         return;
1037     } else if (res == -ENOSYS) {
1038         gdb_put_packet("");
1039         return;
1040     }
1041 
1042     gdb_put_packet("E22");
1043 }
1044 
1045 static void handle_remove_bp(GArray *params, void *user_ctx)
1046 {
1047     int res;
1048 
1049     if (params->len != 3) {
1050         gdb_put_packet("E22");
1051         return;
1052     }
1053 
1054     res = gdb_breakpoint_remove(gdbserver_state.c_cpu,
1055                                 get_param(params, 0)->val_ul,
1056                                 get_param(params, 1)->val_ull,
1057                                 get_param(params, 2)->val_ull);
1058     if (res >= 0) {
1059         gdb_put_packet("OK");
1060         return;
1061     } else if (res == -ENOSYS) {
1062         gdb_put_packet("");
1063         return;
1064     }
1065 
1066     gdb_put_packet("E22");
1067 }
1068 
1069 /*
1070  * handle_set/get_reg
1071  *
1072  * Older gdb are really dumb, and don't use 'G/g' if 'P/p' is available.
1073  * This works, but can be very slow. Anything new enough to understand
1074  * XML also knows how to use this properly. However to use this we
1075  * need to define a local XML file as well as be talking to a
1076  * reasonably modern gdb. Responding with an empty packet will cause
1077  * the remote gdb to fallback to older methods.
1078  */
1079 
1080 static void handle_set_reg(GArray *params, void *user_ctx)
1081 {
1082     int reg_size;
1083 
1084     if (!gdb_get_cpu_process(gdbserver_state.g_cpu)->target_xml) {
1085         gdb_put_packet("");
1086         return;
1087     }
1088 
1089     if (params->len != 2) {
1090         gdb_put_packet("E22");
1091         return;
1092     }
1093 
1094     reg_size = strlen(get_param(params, 1)->data) / 2;
1095     gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, reg_size);
1096     gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data,
1097                        get_param(params, 0)->val_ull);
1098     gdb_put_packet("OK");
1099 }
1100 
1101 static void handle_get_reg(GArray *params, void *user_ctx)
1102 {
1103     int reg_size;
1104 
1105     if (!gdb_get_cpu_process(gdbserver_state.g_cpu)->target_xml) {
1106         gdb_put_packet("");
1107         return;
1108     }
1109 
1110     if (!params->len) {
1111         gdb_put_packet("E14");
1112         return;
1113     }
1114 
1115     reg_size = gdb_read_register(gdbserver_state.g_cpu,
1116                                  gdbserver_state.mem_buf,
1117                                  get_param(params, 0)->val_ull);
1118     if (!reg_size) {
1119         gdb_put_packet("E14");
1120         return;
1121     } else {
1122         g_byte_array_set_size(gdbserver_state.mem_buf, reg_size);
1123     }
1124 
1125     gdb_memtohex(gdbserver_state.str_buf,
1126                  gdbserver_state.mem_buf->data, reg_size);
1127     gdb_put_strbuf();
1128 }
1129 
1130 static void handle_write_mem(GArray *params, void *user_ctx)
1131 {
1132     if (params->len != 3) {
1133         gdb_put_packet("E22");
1134         return;
1135     }
1136 
1137     /* gdb_hextomem() reads 2*len bytes */
1138     if (get_param(params, 1)->val_ull >
1139         strlen(get_param(params, 2)->data) / 2) {
1140         gdb_put_packet("E22");
1141         return;
1142     }
1143 
1144     gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 2)->data,
1145                  get_param(params, 1)->val_ull);
1146     if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu,
1147                                    get_param(params, 0)->val_ull,
1148                                    gdbserver_state.mem_buf->data,
1149                                    gdbserver_state.mem_buf->len, true)) {
1150         gdb_put_packet("E14");
1151         return;
1152     }
1153 
1154     gdb_put_packet("OK");
1155 }
1156 
1157 static void handle_read_mem(GArray *params, void *user_ctx)
1158 {
1159     if (params->len != 2) {
1160         gdb_put_packet("E22");
1161         return;
1162     }
1163 
1164     /* gdb_memtohex() doubles the required space */
1165     if (get_param(params, 1)->val_ull > MAX_PACKET_LENGTH / 2) {
1166         gdb_put_packet("E22");
1167         return;
1168     }
1169 
1170     g_byte_array_set_size(gdbserver_state.mem_buf,
1171                           get_param(params, 1)->val_ull);
1172 
1173     if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu,
1174                                    get_param(params, 0)->val_ull,
1175                                    gdbserver_state.mem_buf->data,
1176                                    gdbserver_state.mem_buf->len, false)) {
1177         gdb_put_packet("E14");
1178         return;
1179     }
1180 
1181     gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data,
1182              gdbserver_state.mem_buf->len);
1183     gdb_put_strbuf();
1184 }
1185 
1186 static void handle_write_all_regs(GArray *params, void *user_ctx)
1187 {
1188     int reg_id;
1189     size_t len;
1190     uint8_t *registers;
1191     int reg_size;
1192 
1193     if (!params->len) {
1194         return;
1195     }
1196 
1197     cpu_synchronize_state(gdbserver_state.g_cpu);
1198     len = strlen(get_param(params, 0)->data) / 2;
1199     gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 0)->data, len);
1200     registers = gdbserver_state.mem_buf->data;
1201     for (reg_id = 0;
1202          reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0;
1203          reg_id++) {
1204         reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id);
1205         len -= reg_size;
1206         registers += reg_size;
1207     }
1208     gdb_put_packet("OK");
1209 }
1210 
1211 static void handle_read_all_regs(GArray *params, void *user_ctx)
1212 {
1213     int reg_id;
1214     size_t len;
1215 
1216     cpu_synchronize_state(gdbserver_state.g_cpu);
1217     g_byte_array_set_size(gdbserver_state.mem_buf, 0);
1218     len = 0;
1219     for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) {
1220         len += gdb_read_register(gdbserver_state.g_cpu,
1221                                  gdbserver_state.mem_buf,
1222                                  reg_id);
1223     }
1224     g_assert(len == gdbserver_state.mem_buf->len);
1225 
1226     gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len);
1227     gdb_put_strbuf();
1228 }
1229 
1230 
1231 static void handle_step(GArray *params, void *user_ctx)
1232 {
1233     if (params->len) {
1234         gdb_set_cpu_pc(get_param(params, 0)->val_ull);
1235     }
1236 
1237     cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags);
1238     gdb_continue();
1239 }
1240 
1241 static void handle_backward(GArray *params, void *user_ctx)
1242 {
1243     if (!gdb_can_reverse()) {
1244         gdb_put_packet("E22");
1245     }
1246     if (params->len == 1) {
1247         switch (get_param(params, 0)->opcode) {
1248         case 's':
1249             if (replay_reverse_step()) {
1250                 gdb_continue();
1251             } else {
1252                 gdb_put_packet("E14");
1253             }
1254             return;
1255         case 'c':
1256             if (replay_reverse_continue()) {
1257                 gdb_continue();
1258             } else {
1259                 gdb_put_packet("E14");
1260             }
1261             return;
1262         }
1263     }
1264 
1265     /* Default invalid command */
1266     gdb_put_packet("");
1267 }
1268 
1269 static void handle_v_cont_query(GArray *params, void *user_ctx)
1270 {
1271     gdb_put_packet("vCont;c;C;s;S");
1272 }
1273 
1274 static void handle_v_cont(GArray *params, void *user_ctx)
1275 {
1276     int res;
1277 
1278     if (!params->len) {
1279         return;
1280     }
1281 
1282     res = gdb_handle_vcont(get_param(params, 0)->data);
1283     if ((res == -EINVAL) || (res == -ERANGE)) {
1284         gdb_put_packet("E22");
1285     } else if (res) {
1286         gdb_put_packet("");
1287     }
1288 }
1289 
1290 static void handle_v_attach(GArray *params, void *user_ctx)
1291 {
1292     GDBProcess *process;
1293     CPUState *cpu;
1294 
1295     g_string_assign(gdbserver_state.str_buf, "E22");
1296     if (!params->len) {
1297         goto cleanup;
1298     }
1299 
1300     process = gdb_get_process(get_param(params, 0)->val_ul);
1301     if (!process) {
1302         goto cleanup;
1303     }
1304 
1305     cpu = gdb_get_first_cpu_in_process(process);
1306     if (!cpu) {
1307         goto cleanup;
1308     }
1309 
1310     process->attached = true;
1311     gdbserver_state.g_cpu = cpu;
1312     gdbserver_state.c_cpu = cpu;
1313 
1314     if (gdbserver_state.allow_stop_reply) {
1315         g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP);
1316         gdb_append_thread_id(cpu, gdbserver_state.str_buf);
1317         g_string_append_c(gdbserver_state.str_buf, ';');
1318         gdbserver_state.allow_stop_reply = false;
1319 cleanup:
1320         gdb_put_strbuf();
1321     }
1322 }
1323 
1324 static void handle_v_kill(GArray *params, void *user_ctx)
1325 {
1326     /* Kill the target */
1327     gdb_put_packet("OK");
1328     error_report("QEMU: Terminated via GDBstub");
1329     gdb_exit(0);
1330     exit(0);
1331 }
1332 
1333 static const GdbCmdParseEntry gdb_v_commands_table[] = {
1334     /* Order is important if has same prefix */
1335     {
1336         .handler = handle_v_cont_query,
1337         .cmd = "Cont?",
1338         .cmd_startswith = 1
1339     },
1340     {
1341         .handler = handle_v_cont,
1342         .cmd = "Cont",
1343         .cmd_startswith = 1,
1344         .allow_stop_reply = true,
1345         .schema = "s0"
1346     },
1347     {
1348         .handler = handle_v_attach,
1349         .cmd = "Attach;",
1350         .cmd_startswith = 1,
1351         .allow_stop_reply = true,
1352         .schema = "l0"
1353     },
1354     {
1355         .handler = handle_v_kill,
1356         .cmd = "Kill;",
1357         .cmd_startswith = 1
1358     },
1359 #ifdef CONFIG_USER_ONLY
1360     /*
1361      * Host I/O Packets. See [1] for details.
1362      * [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html
1363      */
1364     {
1365         .handler = gdb_handle_v_file_open,
1366         .cmd = "File:open:",
1367         .cmd_startswith = 1,
1368         .schema = "s,L,L0"
1369     },
1370     {
1371         .handler = gdb_handle_v_file_close,
1372         .cmd = "File:close:",
1373         .cmd_startswith = 1,
1374         .schema = "l0"
1375     },
1376     {
1377         .handler = gdb_handle_v_file_pread,
1378         .cmd = "File:pread:",
1379         .cmd_startswith = 1,
1380         .schema = "l,L,L0"
1381     },
1382     {
1383         .handler = gdb_handle_v_file_readlink,
1384         .cmd = "File:readlink:",
1385         .cmd_startswith = 1,
1386         .schema = "s0"
1387     },
1388 #endif
1389 };
1390 
1391 static void handle_v_commands(GArray *params, void *user_ctx)
1392 {
1393     if (!params->len) {
1394         return;
1395     }
1396 
1397     if (process_string_cmd(get_param(params, 0)->data,
1398                            gdb_v_commands_table,
1399                            ARRAY_SIZE(gdb_v_commands_table))) {
1400         gdb_put_packet("");
1401     }
1402 }
1403 
1404 static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx)
1405 {
1406     g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE);
1407 
1408     if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) {
1409         g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x",
1410                                SSTEP_NOIRQ);
1411     }
1412 
1413     if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) {
1414         g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x",
1415                                SSTEP_NOTIMER);
1416     }
1417 
1418     gdb_put_strbuf();
1419 }
1420 
1421 static void handle_set_qemu_sstep(GArray *params, void *user_ctx)
1422 {
1423     int new_sstep_flags;
1424 
1425     if (!params->len) {
1426         return;
1427     }
1428 
1429     new_sstep_flags = get_param(params, 0)->val_ul;
1430 
1431     if (new_sstep_flags  & ~gdbserver_state.supported_sstep_flags) {
1432         gdb_put_packet("E22");
1433         return;
1434     }
1435 
1436     gdbserver_state.sstep_flags = new_sstep_flags;
1437     gdb_put_packet("OK");
1438 }
1439 
1440 static void handle_query_qemu_sstep(GArray *params, void *user_ctx)
1441 {
1442     g_string_printf(gdbserver_state.str_buf, "0x%x",
1443                     gdbserver_state.sstep_flags);
1444     gdb_put_strbuf();
1445 }
1446 
1447 static void handle_query_curr_tid(GArray *params, void *user_ctx)
1448 {
1449     CPUState *cpu;
1450     GDBProcess *process;
1451 
1452     /*
1453      * "Current thread" remains vague in the spec, so always return
1454      * the first thread of the current process (gdb returns the
1455      * first thread).
1456      */
1457     process = gdb_get_cpu_process(gdbserver_state.g_cpu);
1458     cpu = gdb_get_first_cpu_in_process(process);
1459     g_string_assign(gdbserver_state.str_buf, "QC");
1460     gdb_append_thread_id(cpu, gdbserver_state.str_buf);
1461     gdb_put_strbuf();
1462 }
1463 
1464 static void handle_query_threads(GArray *params, void *user_ctx)
1465 {
1466     if (!gdbserver_state.query_cpu) {
1467         gdb_put_packet("l");
1468         return;
1469     }
1470 
1471     g_string_assign(gdbserver_state.str_buf, "m");
1472     gdb_append_thread_id(gdbserver_state.query_cpu, gdbserver_state.str_buf);
1473     gdb_put_strbuf();
1474     gdbserver_state.query_cpu = gdb_next_attached_cpu(gdbserver_state.query_cpu);
1475 }
1476 
1477 static void handle_query_first_threads(GArray *params, void *user_ctx)
1478 {
1479     gdbserver_state.query_cpu = gdb_first_attached_cpu();
1480     handle_query_threads(params, user_ctx);
1481 }
1482 
1483 static void handle_query_thread_extra(GArray *params, void *user_ctx)
1484 {
1485     g_autoptr(GString) rs = g_string_new(NULL);
1486     CPUState *cpu;
1487 
1488     if (!params->len ||
1489         get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) {
1490         gdb_put_packet("E22");
1491         return;
1492     }
1493 
1494     cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid,
1495                       get_param(params, 0)->thread_id.tid);
1496     if (!cpu) {
1497         return;
1498     }
1499 
1500     cpu_synchronize_state(cpu);
1501 
1502     if (gdbserver_state.multiprocess && (gdbserver_state.process_num > 1)) {
1503         /* Print the CPU model and name in multiprocess mode */
1504         ObjectClass *oc = object_get_class(OBJECT(cpu));
1505         const char *cpu_model = object_class_get_name(oc);
1506         const char *cpu_name =
1507             object_get_canonical_path_component(OBJECT(cpu));
1508         g_string_printf(rs, "%s %s [%s]", cpu_model, cpu_name,
1509                         cpu->halted ? "halted " : "running");
1510     } else {
1511         g_string_printf(rs, "CPU#%d [%s]", cpu->cpu_index,
1512                         cpu->halted ? "halted " : "running");
1513     }
1514     trace_gdbstub_op_extra_info(rs->str);
1515     gdb_memtohex(gdbserver_state.str_buf, (uint8_t *)rs->str, rs->len);
1516     gdb_put_strbuf();
1517 }
1518 
1519 static void handle_query_supported(GArray *params, void *user_ctx)
1520 {
1521     CPUClass *cc;
1522 
1523     g_string_printf(gdbserver_state.str_buf, "PacketSize=%x", MAX_PACKET_LENGTH);
1524     cc = CPU_GET_CLASS(first_cpu);
1525     if (cc->gdb_core_xml_file) {
1526         g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+");
1527     }
1528 
1529     if (gdb_can_reverse()) {
1530         g_string_append(gdbserver_state.str_buf,
1531             ";ReverseStep+;ReverseContinue+");
1532     }
1533 
1534 #if defined(CONFIG_USER_ONLY)
1535 #if defined(CONFIG_LINUX)
1536     if (gdbserver_state.c_cpu->opaque) {
1537         g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+");
1538     }
1539 #endif
1540     g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+");
1541 #endif
1542 
1543     if (params->len &&
1544         strstr(get_param(params, 0)->data, "multiprocess+")) {
1545         gdbserver_state.multiprocess = true;
1546     }
1547 
1548     g_string_append(gdbserver_state.str_buf, ";vContSupported+;multiprocess+");
1549     gdb_put_strbuf();
1550 }
1551 
1552 static void handle_query_xfer_features(GArray *params, void *user_ctx)
1553 {
1554     GDBProcess *process;
1555     CPUClass *cc;
1556     unsigned long len, total_len, addr;
1557     const char *xml;
1558     const char *p;
1559 
1560     if (params->len < 3) {
1561         gdb_put_packet("E22");
1562         return;
1563     }
1564 
1565     process = gdb_get_cpu_process(gdbserver_state.g_cpu);
1566     cc = CPU_GET_CLASS(gdbserver_state.g_cpu);
1567     if (!cc->gdb_core_xml_file) {
1568         gdb_put_packet("");
1569         return;
1570     }
1571 
1572     p = get_param(params, 0)->data;
1573     xml = get_feature_xml(p, &p, process);
1574     if (!xml) {
1575         gdb_put_packet("E00");
1576         return;
1577     }
1578 
1579     addr = get_param(params, 1)->val_ul;
1580     len = get_param(params, 2)->val_ul;
1581     total_len = strlen(xml);
1582     if (addr > total_len) {
1583         gdb_put_packet("E00");
1584         return;
1585     }
1586 
1587     if (len > (MAX_PACKET_LENGTH - 5) / 2) {
1588         len = (MAX_PACKET_LENGTH - 5) / 2;
1589     }
1590 
1591     if (len < total_len - addr) {
1592         g_string_assign(gdbserver_state.str_buf, "m");
1593         gdb_memtox(gdbserver_state.str_buf, xml + addr, len);
1594     } else {
1595         g_string_assign(gdbserver_state.str_buf, "l");
1596         gdb_memtox(gdbserver_state.str_buf, xml + addr, total_len - addr);
1597     }
1598 
1599     gdb_put_packet_binary(gdbserver_state.str_buf->str,
1600                       gdbserver_state.str_buf->len, true);
1601 }
1602 
1603 static void handle_query_qemu_supported(GArray *params, void *user_ctx)
1604 {
1605     g_string_printf(gdbserver_state.str_buf, "sstepbits;sstep");
1606 #ifndef CONFIG_USER_ONLY
1607     g_string_append(gdbserver_state.str_buf, ";PhyMemMode");
1608 #endif
1609     gdb_put_strbuf();
1610 }
1611 
1612 static const GdbCmdParseEntry gdb_gen_query_set_common_table[] = {
1613     /* Order is important if has same prefix */
1614     {
1615         .handler = handle_query_qemu_sstepbits,
1616         .cmd = "qemu.sstepbits",
1617     },
1618     {
1619         .handler = handle_query_qemu_sstep,
1620         .cmd = "qemu.sstep",
1621     },
1622     {
1623         .handler = handle_set_qemu_sstep,
1624         .cmd = "qemu.sstep=",
1625         .cmd_startswith = 1,
1626         .schema = "l0"
1627     },
1628 };
1629 
1630 static const GdbCmdParseEntry gdb_gen_query_table[] = {
1631     {
1632         .handler = handle_query_curr_tid,
1633         .cmd = "C",
1634     },
1635     {
1636         .handler = handle_query_threads,
1637         .cmd = "sThreadInfo",
1638     },
1639     {
1640         .handler = handle_query_first_threads,
1641         .cmd = "fThreadInfo",
1642     },
1643     {
1644         .handler = handle_query_thread_extra,
1645         .cmd = "ThreadExtraInfo,",
1646         .cmd_startswith = 1,
1647         .schema = "t0"
1648     },
1649 #ifdef CONFIG_USER_ONLY
1650     {
1651         .handler = gdb_handle_query_offsets,
1652         .cmd = "Offsets",
1653     },
1654 #else
1655     {
1656         .handler = gdb_handle_query_rcmd,
1657         .cmd = "Rcmd,",
1658         .cmd_startswith = 1,
1659         .schema = "s0"
1660     },
1661 #endif
1662     {
1663         .handler = handle_query_supported,
1664         .cmd = "Supported:",
1665         .cmd_startswith = 1,
1666         .schema = "s0"
1667     },
1668     {
1669         .handler = handle_query_supported,
1670         .cmd = "Supported",
1671         .schema = "s0"
1672     },
1673     {
1674         .handler = handle_query_xfer_features,
1675         .cmd = "Xfer:features:read:",
1676         .cmd_startswith = 1,
1677         .schema = "s:l,l0"
1678     },
1679 #if defined(CONFIG_USER_ONLY)
1680 #if defined(CONFIG_LINUX)
1681     {
1682         .handler = gdb_handle_query_xfer_auxv,
1683         .cmd = "Xfer:auxv:read::",
1684         .cmd_startswith = 1,
1685         .schema = "l,l0"
1686     },
1687 #endif
1688     {
1689         .handler = gdb_handle_query_xfer_exec_file,
1690         .cmd = "Xfer:exec-file:read:",
1691         .cmd_startswith = 1,
1692         .schema = "l:l,l0"
1693     },
1694 #endif
1695     {
1696         .handler = gdb_handle_query_attached,
1697         .cmd = "Attached:",
1698         .cmd_startswith = 1
1699     },
1700     {
1701         .handler = gdb_handle_query_attached,
1702         .cmd = "Attached",
1703     },
1704     {
1705         .handler = handle_query_qemu_supported,
1706         .cmd = "qemu.Supported",
1707     },
1708 #ifndef CONFIG_USER_ONLY
1709     {
1710         .handler = gdb_handle_query_qemu_phy_mem_mode,
1711         .cmd = "qemu.PhyMemMode",
1712     },
1713 #endif
1714 };
1715 
1716 static const GdbCmdParseEntry gdb_gen_set_table[] = {
1717     /* Order is important if has same prefix */
1718     {
1719         .handler = handle_set_qemu_sstep,
1720         .cmd = "qemu.sstep:",
1721         .cmd_startswith = 1,
1722         .schema = "l0"
1723     },
1724 #ifndef CONFIG_USER_ONLY
1725     {
1726         .handler = gdb_handle_set_qemu_phy_mem_mode,
1727         .cmd = "qemu.PhyMemMode:",
1728         .cmd_startswith = 1,
1729         .schema = "l0"
1730     },
1731 #endif
1732 };
1733 
1734 static void handle_gen_query(GArray *params, void *user_ctx)
1735 {
1736     if (!params->len) {
1737         return;
1738     }
1739 
1740     if (!process_string_cmd(get_param(params, 0)->data,
1741                             gdb_gen_query_set_common_table,
1742                             ARRAY_SIZE(gdb_gen_query_set_common_table))) {
1743         return;
1744     }
1745 
1746     if (process_string_cmd(get_param(params, 0)->data,
1747                            gdb_gen_query_table,
1748                            ARRAY_SIZE(gdb_gen_query_table))) {
1749         gdb_put_packet("");
1750     }
1751 }
1752 
1753 static void handle_gen_set(GArray *params, void *user_ctx)
1754 {
1755     if (!params->len) {
1756         return;
1757     }
1758 
1759     if (!process_string_cmd(get_param(params, 0)->data,
1760                             gdb_gen_query_set_common_table,
1761                             ARRAY_SIZE(gdb_gen_query_set_common_table))) {
1762         return;
1763     }
1764 
1765     if (process_string_cmd(get_param(params, 0)->data,
1766                            gdb_gen_set_table,
1767                            ARRAY_SIZE(gdb_gen_set_table))) {
1768         gdb_put_packet("");
1769     }
1770 }
1771 
1772 static void handle_target_halt(GArray *params, void *user_ctx)
1773 {
1774     if (gdbserver_state.allow_stop_reply) {
1775         g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP);
1776         gdb_append_thread_id(gdbserver_state.c_cpu, gdbserver_state.str_buf);
1777         g_string_append_c(gdbserver_state.str_buf, ';');
1778         gdb_put_strbuf();
1779         gdbserver_state.allow_stop_reply = false;
1780     }
1781     /*
1782      * Remove all the breakpoints when this query is issued,
1783      * because gdb is doing an initial connect and the state
1784      * should be cleaned up.
1785      */
1786     gdb_breakpoint_remove_all(gdbserver_state.c_cpu);
1787 }
1788 
1789 static int gdb_handle_packet(const char *line_buf)
1790 {
1791     const GdbCmdParseEntry *cmd_parser = NULL;
1792 
1793     trace_gdbstub_io_command(line_buf);
1794 
1795     switch (line_buf[0]) {
1796     case '!':
1797         gdb_put_packet("OK");
1798         break;
1799     case '?':
1800         {
1801             static const GdbCmdParseEntry target_halted_cmd_desc = {
1802                 .handler = handle_target_halt,
1803                 .cmd = "?",
1804                 .cmd_startswith = 1,
1805                 .allow_stop_reply = true,
1806             };
1807             cmd_parser = &target_halted_cmd_desc;
1808         }
1809         break;
1810     case 'c':
1811         {
1812             static const GdbCmdParseEntry continue_cmd_desc = {
1813                 .handler = handle_continue,
1814                 .cmd = "c",
1815                 .cmd_startswith = 1,
1816                 .allow_stop_reply = true,
1817                 .schema = "L0"
1818             };
1819             cmd_parser = &continue_cmd_desc;
1820         }
1821         break;
1822     case 'C':
1823         {
1824             static const GdbCmdParseEntry cont_with_sig_cmd_desc = {
1825                 .handler = handle_cont_with_sig,
1826                 .cmd = "C",
1827                 .cmd_startswith = 1,
1828                 .allow_stop_reply = true,
1829                 .schema = "l0"
1830             };
1831             cmd_parser = &cont_with_sig_cmd_desc;
1832         }
1833         break;
1834     case 'v':
1835         {
1836             static const GdbCmdParseEntry v_cmd_desc = {
1837                 .handler = handle_v_commands,
1838                 .cmd = "v",
1839                 .cmd_startswith = 1,
1840                 .schema = "s0"
1841             };
1842             cmd_parser = &v_cmd_desc;
1843         }
1844         break;
1845     case 'k':
1846         /* Kill the target */
1847         error_report("QEMU: Terminated via GDBstub");
1848         gdb_exit(0);
1849         exit(0);
1850     case 'D':
1851         {
1852             static const GdbCmdParseEntry detach_cmd_desc = {
1853                 .handler = handle_detach,
1854                 .cmd = "D",
1855                 .cmd_startswith = 1,
1856                 .schema = "?.l0"
1857             };
1858             cmd_parser = &detach_cmd_desc;
1859         }
1860         break;
1861     case 's':
1862         {
1863             static const GdbCmdParseEntry step_cmd_desc = {
1864                 .handler = handle_step,
1865                 .cmd = "s",
1866                 .cmd_startswith = 1,
1867                 .allow_stop_reply = true,
1868                 .schema = "L0"
1869             };
1870             cmd_parser = &step_cmd_desc;
1871         }
1872         break;
1873     case 'b':
1874         {
1875             static const GdbCmdParseEntry backward_cmd_desc = {
1876                 .handler = handle_backward,
1877                 .cmd = "b",
1878                 .cmd_startswith = 1,
1879                 .allow_stop_reply = true,
1880                 .schema = "o0"
1881             };
1882             cmd_parser = &backward_cmd_desc;
1883         }
1884         break;
1885     case 'F':
1886         {
1887             static const GdbCmdParseEntry file_io_cmd_desc = {
1888                 .handler = gdb_handle_file_io,
1889                 .cmd = "F",
1890                 .cmd_startswith = 1,
1891                 .schema = "L,L,o0"
1892             };
1893             cmd_parser = &file_io_cmd_desc;
1894         }
1895         break;
1896     case 'g':
1897         {
1898             static const GdbCmdParseEntry read_all_regs_cmd_desc = {
1899                 .handler = handle_read_all_regs,
1900                 .cmd = "g",
1901                 .cmd_startswith = 1
1902             };
1903             cmd_parser = &read_all_regs_cmd_desc;
1904         }
1905         break;
1906     case 'G':
1907         {
1908             static const GdbCmdParseEntry write_all_regs_cmd_desc = {
1909                 .handler = handle_write_all_regs,
1910                 .cmd = "G",
1911                 .cmd_startswith = 1,
1912                 .schema = "s0"
1913             };
1914             cmd_parser = &write_all_regs_cmd_desc;
1915         }
1916         break;
1917     case 'm':
1918         {
1919             static const GdbCmdParseEntry read_mem_cmd_desc = {
1920                 .handler = handle_read_mem,
1921                 .cmd = "m",
1922                 .cmd_startswith = 1,
1923                 .schema = "L,L0"
1924             };
1925             cmd_parser = &read_mem_cmd_desc;
1926         }
1927         break;
1928     case 'M':
1929         {
1930             static const GdbCmdParseEntry write_mem_cmd_desc = {
1931                 .handler = handle_write_mem,
1932                 .cmd = "M",
1933                 .cmd_startswith = 1,
1934                 .schema = "L,L:s0"
1935             };
1936             cmd_parser = &write_mem_cmd_desc;
1937         }
1938         break;
1939     case 'p':
1940         {
1941             static const GdbCmdParseEntry get_reg_cmd_desc = {
1942                 .handler = handle_get_reg,
1943                 .cmd = "p",
1944                 .cmd_startswith = 1,
1945                 .schema = "L0"
1946             };
1947             cmd_parser = &get_reg_cmd_desc;
1948         }
1949         break;
1950     case 'P':
1951         {
1952             static const GdbCmdParseEntry set_reg_cmd_desc = {
1953                 .handler = handle_set_reg,
1954                 .cmd = "P",
1955                 .cmd_startswith = 1,
1956                 .schema = "L?s0"
1957             };
1958             cmd_parser = &set_reg_cmd_desc;
1959         }
1960         break;
1961     case 'Z':
1962         {
1963             static const GdbCmdParseEntry insert_bp_cmd_desc = {
1964                 .handler = handle_insert_bp,
1965                 .cmd = "Z",
1966                 .cmd_startswith = 1,
1967                 .schema = "l?L?L0"
1968             };
1969             cmd_parser = &insert_bp_cmd_desc;
1970         }
1971         break;
1972     case 'z':
1973         {
1974             static const GdbCmdParseEntry remove_bp_cmd_desc = {
1975                 .handler = handle_remove_bp,
1976                 .cmd = "z",
1977                 .cmd_startswith = 1,
1978                 .schema = "l?L?L0"
1979             };
1980             cmd_parser = &remove_bp_cmd_desc;
1981         }
1982         break;
1983     case 'H':
1984         {
1985             static const GdbCmdParseEntry set_thread_cmd_desc = {
1986                 .handler = handle_set_thread,
1987                 .cmd = "H",
1988                 .cmd_startswith = 1,
1989                 .schema = "o.t0"
1990             };
1991             cmd_parser = &set_thread_cmd_desc;
1992         }
1993         break;
1994     case 'T':
1995         {
1996             static const GdbCmdParseEntry thread_alive_cmd_desc = {
1997                 .handler = handle_thread_alive,
1998                 .cmd = "T",
1999                 .cmd_startswith = 1,
2000                 .schema = "t0"
2001             };
2002             cmd_parser = &thread_alive_cmd_desc;
2003         }
2004         break;
2005     case 'q':
2006         {
2007             static const GdbCmdParseEntry gen_query_cmd_desc = {
2008                 .handler = handle_gen_query,
2009                 .cmd = "q",
2010                 .cmd_startswith = 1,
2011                 .schema = "s0"
2012             };
2013             cmd_parser = &gen_query_cmd_desc;
2014         }
2015         break;
2016     case 'Q':
2017         {
2018             static const GdbCmdParseEntry gen_set_cmd_desc = {
2019                 .handler = handle_gen_set,
2020                 .cmd = "Q",
2021                 .cmd_startswith = 1,
2022                 .schema = "s0"
2023             };
2024             cmd_parser = &gen_set_cmd_desc;
2025         }
2026         break;
2027     default:
2028         /* put empty packet */
2029         gdb_put_packet("");
2030         break;
2031     }
2032 
2033     if (cmd_parser) {
2034         run_cmd_parser(line_buf, cmd_parser);
2035     }
2036 
2037     return RS_IDLE;
2038 }
2039 
2040 void gdb_set_stop_cpu(CPUState *cpu)
2041 {
2042     GDBProcess *p = gdb_get_cpu_process(cpu);
2043 
2044     if (!p->attached) {
2045         /*
2046          * Having a stop CPU corresponding to a process that is not attached
2047          * confuses GDB. So we ignore the request.
2048          */
2049         return;
2050     }
2051 
2052     gdbserver_state.c_cpu = cpu;
2053     gdbserver_state.g_cpu = cpu;
2054 }
2055 
2056 void gdb_read_byte(uint8_t ch)
2057 {
2058     uint8_t reply;
2059 
2060     gdbserver_state.allow_stop_reply = false;
2061 #ifndef CONFIG_USER_ONLY
2062     if (gdbserver_state.last_packet->len) {
2063         /* Waiting for a response to the last packet.  If we see the start
2064            of a new command then abandon the previous response.  */
2065         if (ch == '-') {
2066             trace_gdbstub_err_got_nack();
2067             gdb_put_buffer(gdbserver_state.last_packet->data,
2068                        gdbserver_state.last_packet->len);
2069         } else if (ch == '+') {
2070             trace_gdbstub_io_got_ack();
2071         } else {
2072             trace_gdbstub_io_got_unexpected(ch);
2073         }
2074 
2075         if (ch == '+' || ch == '$') {
2076             g_byte_array_set_size(gdbserver_state.last_packet, 0);
2077         }
2078         if (ch != '$')
2079             return;
2080     }
2081     if (runstate_is_running()) {
2082         /*
2083          * When the CPU is running, we cannot do anything except stop
2084          * it when receiving a char. This is expected on a Ctrl-C in the
2085          * gdb client. Because we are in all-stop mode, gdb sends a
2086          * 0x03 byte which is not a usual packet, so we handle it specially
2087          * here, but it does expect a stop reply.
2088          */
2089         if (ch != 0x03) {
2090             trace_gdbstub_err_unexpected_runpkt(ch);
2091         } else {
2092             gdbserver_state.allow_stop_reply = true;
2093         }
2094         vm_stop(RUN_STATE_PAUSED);
2095     } else
2096 #endif
2097     {
2098         switch(gdbserver_state.state) {
2099         case RS_IDLE:
2100             if (ch == '$') {
2101                 /* start of command packet */
2102                 gdbserver_state.line_buf_index = 0;
2103                 gdbserver_state.line_sum = 0;
2104                 gdbserver_state.state = RS_GETLINE;
2105             } else if (ch == '+') {
2106                 /*
2107                  * do nothing, gdb may preemptively send out ACKs on
2108                  * initial connection
2109                  */
2110             } else {
2111                 trace_gdbstub_err_garbage(ch);
2112             }
2113             break;
2114         case RS_GETLINE:
2115             if (ch == '}') {
2116                 /* start escape sequence */
2117                 gdbserver_state.state = RS_GETLINE_ESC;
2118                 gdbserver_state.line_sum += ch;
2119             } else if (ch == '*') {
2120                 /* start run length encoding sequence */
2121                 gdbserver_state.state = RS_GETLINE_RLE;
2122                 gdbserver_state.line_sum += ch;
2123             } else if (ch == '#') {
2124                 /* end of command, start of checksum*/
2125                 gdbserver_state.state = RS_CHKSUM1;
2126             } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) {
2127                 trace_gdbstub_err_overrun();
2128                 gdbserver_state.state = RS_IDLE;
2129             } else {
2130                 /* unescaped command character */
2131                 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch;
2132                 gdbserver_state.line_sum += ch;
2133             }
2134             break;
2135         case RS_GETLINE_ESC:
2136             if (ch == '#') {
2137                 /* unexpected end of command in escape sequence */
2138                 gdbserver_state.state = RS_CHKSUM1;
2139             } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) {
2140                 /* command buffer overrun */
2141                 trace_gdbstub_err_overrun();
2142                 gdbserver_state.state = RS_IDLE;
2143             } else {
2144                 /* parse escaped character and leave escape state */
2145                 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch ^ 0x20;
2146                 gdbserver_state.line_sum += ch;
2147                 gdbserver_state.state = RS_GETLINE;
2148             }
2149             break;
2150         case RS_GETLINE_RLE:
2151             /*
2152              * Run-length encoding is explained in "Debugging with GDB /
2153              * Appendix E GDB Remote Serial Protocol / Overview".
2154              */
2155             if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) {
2156                 /* invalid RLE count encoding */
2157                 trace_gdbstub_err_invalid_repeat(ch);
2158                 gdbserver_state.state = RS_GETLINE;
2159             } else {
2160                 /* decode repeat length */
2161                 int repeat = ch - ' ' + 3;
2162                 if (gdbserver_state.line_buf_index + repeat >= sizeof(gdbserver_state.line_buf) - 1) {
2163                     /* that many repeats would overrun the command buffer */
2164                     trace_gdbstub_err_overrun();
2165                     gdbserver_state.state = RS_IDLE;
2166                 } else if (gdbserver_state.line_buf_index < 1) {
2167                     /* got a repeat but we have nothing to repeat */
2168                     trace_gdbstub_err_invalid_rle();
2169                     gdbserver_state.state = RS_GETLINE;
2170                 } else {
2171                     /* repeat the last character */
2172                     memset(gdbserver_state.line_buf + gdbserver_state.line_buf_index,
2173                            gdbserver_state.line_buf[gdbserver_state.line_buf_index - 1], repeat);
2174                     gdbserver_state.line_buf_index += repeat;
2175                     gdbserver_state.line_sum += ch;
2176                     gdbserver_state.state = RS_GETLINE;
2177                 }
2178             }
2179             break;
2180         case RS_CHKSUM1:
2181             /* get high hex digit of checksum */
2182             if (!isxdigit(ch)) {
2183                 trace_gdbstub_err_checksum_invalid(ch);
2184                 gdbserver_state.state = RS_GETLINE;
2185                 break;
2186             }
2187             gdbserver_state.line_buf[gdbserver_state.line_buf_index] = '\0';
2188             gdbserver_state.line_csum = fromhex(ch) << 4;
2189             gdbserver_state.state = RS_CHKSUM2;
2190             break;
2191         case RS_CHKSUM2:
2192             /* get low hex digit of checksum */
2193             if (!isxdigit(ch)) {
2194                 trace_gdbstub_err_checksum_invalid(ch);
2195                 gdbserver_state.state = RS_GETLINE;
2196                 break;
2197             }
2198             gdbserver_state.line_csum |= fromhex(ch);
2199 
2200             if (gdbserver_state.line_csum != (gdbserver_state.line_sum & 0xff)) {
2201                 trace_gdbstub_err_checksum_incorrect(gdbserver_state.line_sum, gdbserver_state.line_csum);
2202                 /* send NAK reply */
2203                 reply = '-';
2204                 gdb_put_buffer(&reply, 1);
2205                 gdbserver_state.state = RS_IDLE;
2206             } else {
2207                 /* send ACK reply */
2208                 reply = '+';
2209                 gdb_put_buffer(&reply, 1);
2210                 gdbserver_state.state = gdb_handle_packet(gdbserver_state.line_buf);
2211             }
2212             break;
2213         default:
2214             abort();
2215         }
2216     }
2217 }
2218 
2219 /*
2220  * Create the process that will contain all the "orphan" CPUs (that are not
2221  * part of a CPU cluster). Note that if this process contains no CPUs, it won't
2222  * be attachable and thus will be invisible to the user.
2223  */
2224 void gdb_create_default_process(GDBState *s)
2225 {
2226     GDBProcess *process;
2227     int pid;
2228 
2229 #ifdef CONFIG_USER_ONLY
2230     assert(gdbserver_state.process_num == 0);
2231     pid = getpid();
2232 #else
2233     if (gdbserver_state.process_num) {
2234         pid = s->processes[s->process_num - 1].pid;
2235     } else {
2236         pid = 0;
2237     }
2238     /* We need an available PID slot for this process */
2239     assert(pid < UINT32_MAX);
2240     pid++;
2241 #endif
2242 
2243     s->processes = g_renew(GDBProcess, s->processes, ++s->process_num);
2244     process = &s->processes[s->process_num - 1];
2245     process->pid = pid;
2246     process->attached = false;
2247     process->target_xml = NULL;
2248 }
2249 
2250