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