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 } GDBRegisterState; 55 56 GDBState gdbserver_state; 57 58 void gdb_init_gdbserver_state(void) 59 { 60 g_assert(!gdbserver_state.init); 61 memset(&gdbserver_state, 0, sizeof(GDBState)); 62 gdbserver_state.init = true; 63 gdbserver_state.str_buf = g_string_new(NULL); 64 gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH); 65 gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4); 66 67 /* 68 * What single-step modes are supported is accelerator dependent. 69 * By default try to use no IRQs and no timers while single 70 * stepping so as to make single stepping like a typical ICE HW step. 71 */ 72 gdbserver_state.supported_sstep_flags = accel_supported_gdbstub_sstep_flags(); 73 gdbserver_state.sstep_flags = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER; 74 gdbserver_state.sstep_flags &= gdbserver_state.supported_sstep_flags; 75 } 76 77 /* writes 2*len+1 bytes in buf */ 78 void gdb_memtohex(GString *buf, const uint8_t *mem, int len) 79 { 80 int i, c; 81 for(i = 0; i < len; i++) { 82 c = mem[i]; 83 g_string_append_c(buf, tohex(c >> 4)); 84 g_string_append_c(buf, tohex(c & 0xf)); 85 } 86 g_string_append_c(buf, '\0'); 87 } 88 89 void gdb_hextomem(GByteArray *mem, const char *buf, int len) 90 { 91 int i; 92 93 for(i = 0; i < len; i++) { 94 guint8 byte = fromhex(buf[0]) << 4 | fromhex(buf[1]); 95 g_byte_array_append(mem, &byte, 1); 96 buf += 2; 97 } 98 } 99 100 static void hexdump(const char *buf, int len, 101 void (*trace_fn)(size_t ofs, char const *text)) 102 { 103 char line_buffer[3 * 16 + 4 + 16 + 1]; 104 105 size_t i; 106 for (i = 0; i < len || (i & 0xF); ++i) { 107 size_t byte_ofs = i & 15; 108 109 if (byte_ofs == 0) { 110 memset(line_buffer, ' ', 3 * 16 + 4 + 16); 111 line_buffer[3 * 16 + 4 + 16] = 0; 112 } 113 114 size_t col_group = (i >> 2) & 3; 115 size_t hex_col = byte_ofs * 3 + col_group; 116 size_t txt_col = 3 * 16 + 4 + byte_ofs; 117 118 if (i < len) { 119 char value = buf[i]; 120 121 line_buffer[hex_col + 0] = tohex((value >> 4) & 0xF); 122 line_buffer[hex_col + 1] = tohex((value >> 0) & 0xF); 123 line_buffer[txt_col + 0] = (value >= ' ' && value < 127) 124 ? value 125 : '.'; 126 } 127 128 if (byte_ofs == 0xF) 129 trace_fn(i & -16, line_buffer); 130 } 131 } 132 133 /* return -1 if error, 0 if OK */ 134 int gdb_put_packet_binary(const char *buf, int len, bool dump) 135 { 136 int csum, i; 137 uint8_t footer[3]; 138 139 if (dump && trace_event_get_state_backends(TRACE_GDBSTUB_IO_BINARYREPLY)) { 140 hexdump(buf, len, trace_gdbstub_io_binaryreply); 141 } 142 143 for(;;) { 144 g_byte_array_set_size(gdbserver_state.last_packet, 0); 145 g_byte_array_append(gdbserver_state.last_packet, 146 (const uint8_t *) "$", 1); 147 g_byte_array_append(gdbserver_state.last_packet, 148 (const uint8_t *) buf, len); 149 csum = 0; 150 for(i = 0; i < len; i++) { 151 csum += buf[i]; 152 } 153 footer[0] = '#'; 154 footer[1] = tohex((csum >> 4) & 0xf); 155 footer[2] = tohex((csum) & 0xf); 156 g_byte_array_append(gdbserver_state.last_packet, footer, 3); 157 158 gdb_put_buffer(gdbserver_state.last_packet->data, 159 gdbserver_state.last_packet->len); 160 161 if (gdb_got_immediate_ack()) { 162 break; 163 } 164 } 165 return 0; 166 } 167 168 /* return -1 if error, 0 if OK */ 169 int gdb_put_packet(const char *buf) 170 { 171 trace_gdbstub_io_reply(buf); 172 173 return gdb_put_packet_binary(buf, strlen(buf), false); 174 } 175 176 void gdb_put_strbuf(void) 177 { 178 gdb_put_packet(gdbserver_state.str_buf->str); 179 } 180 181 /* Encode data using the encoding for 'x' packets. */ 182 void gdb_memtox(GString *buf, const char *mem, int len) 183 { 184 char c; 185 186 while (len--) { 187 c = *(mem++); 188 switch (c) { 189 case '#': case '$': case '*': case '}': 190 g_string_append_c(buf, '}'); 191 g_string_append_c(buf, c ^ 0x20); 192 break; 193 default: 194 g_string_append_c(buf, c); 195 break; 196 } 197 } 198 } 199 200 static uint32_t gdb_get_cpu_pid(CPUState *cpu) 201 { 202 #ifdef CONFIG_USER_ONLY 203 return getpid(); 204 #else 205 if (cpu->cluster_index == UNASSIGNED_CLUSTER_INDEX) { 206 /* Return the default process' PID */ 207 int index = gdbserver_state.process_num - 1; 208 return gdbserver_state.processes[index].pid; 209 } 210 return cpu->cluster_index + 1; 211 #endif 212 } 213 214 GDBProcess *gdb_get_process(uint32_t pid) 215 { 216 int i; 217 218 if (!pid) { 219 /* 0 means any process, we take the first one */ 220 return &gdbserver_state.processes[0]; 221 } 222 223 for (i = 0; i < gdbserver_state.process_num; i++) { 224 if (gdbserver_state.processes[i].pid == pid) { 225 return &gdbserver_state.processes[i]; 226 } 227 } 228 229 return NULL; 230 } 231 232 static GDBProcess *gdb_get_cpu_process(CPUState *cpu) 233 { 234 return gdb_get_process(gdb_get_cpu_pid(cpu)); 235 } 236 237 static CPUState *find_cpu(uint32_t thread_id) 238 { 239 CPUState *cpu; 240 241 CPU_FOREACH(cpu) { 242 if (gdb_get_cpu_index(cpu) == thread_id) { 243 return cpu; 244 } 245 } 246 247 return NULL; 248 } 249 250 CPUState *gdb_get_first_cpu_in_process(GDBProcess *process) 251 { 252 CPUState *cpu; 253 254 CPU_FOREACH(cpu) { 255 if (gdb_get_cpu_pid(cpu) == process->pid) { 256 return cpu; 257 } 258 } 259 260 return NULL; 261 } 262 263 static CPUState *gdb_next_cpu_in_process(CPUState *cpu) 264 { 265 uint32_t pid = gdb_get_cpu_pid(cpu); 266 cpu = CPU_NEXT(cpu); 267 268 while (cpu) { 269 if (gdb_get_cpu_pid(cpu) == pid) { 270 break; 271 } 272 273 cpu = CPU_NEXT(cpu); 274 } 275 276 return cpu; 277 } 278 279 /* Return the cpu following @cpu, while ignoring unattached processes. */ 280 static CPUState *gdb_next_attached_cpu(CPUState *cpu) 281 { 282 cpu = CPU_NEXT(cpu); 283 284 while (cpu) { 285 if (gdb_get_cpu_process(cpu)->attached) { 286 break; 287 } 288 289 cpu = CPU_NEXT(cpu); 290 } 291 292 return cpu; 293 } 294 295 /* Return the first attached cpu */ 296 CPUState *gdb_first_attached_cpu(void) 297 { 298 CPUState *cpu = first_cpu; 299 GDBProcess *process = gdb_get_cpu_process(cpu); 300 301 if (!process->attached) { 302 return gdb_next_attached_cpu(cpu); 303 } 304 305 return cpu; 306 } 307 308 static CPUState *gdb_get_cpu(uint32_t pid, uint32_t tid) 309 { 310 GDBProcess *process; 311 CPUState *cpu; 312 313 if (!pid && !tid) { 314 /* 0 means any process/thread, we take the first attached one */ 315 return gdb_first_attached_cpu(); 316 } else if (pid && !tid) { 317 /* any thread in a specific process */ 318 process = gdb_get_process(pid); 319 320 if (process == NULL) { 321 return NULL; 322 } 323 324 if (!process->attached) { 325 return NULL; 326 } 327 328 return gdb_get_first_cpu_in_process(process); 329 } else { 330 /* a specific thread */ 331 cpu = find_cpu(tid); 332 333 if (cpu == NULL) { 334 return NULL; 335 } 336 337 process = gdb_get_cpu_process(cpu); 338 339 if (pid && process->pid != pid) { 340 return NULL; 341 } 342 343 if (!process->attached) { 344 return NULL; 345 } 346 347 return cpu; 348 } 349 } 350 351 static const char *get_feature_xml(const char *p, const char **newp, 352 GDBProcess *process) 353 { 354 CPUState *cpu = gdb_get_first_cpu_in_process(process); 355 CPUClass *cc = CPU_GET_CLASS(cpu); 356 size_t len; 357 358 /* 359 * qXfer:features:read:ANNEX:OFFSET,LENGTH' 360 * ^p ^newp 361 */ 362 char *term = strchr(p, ':'); 363 *newp = term + 1; 364 len = term - p; 365 366 /* Is it the main target xml? */ 367 if (strncmp(p, "target.xml", len) == 0) { 368 if (!process->target_xml) { 369 GDBRegisterState *r; 370 g_autoptr(GPtrArray) xml = g_ptr_array_new_with_free_func(g_free); 371 372 g_ptr_array_add( 373 xml, 374 g_strdup("<?xml version=\"1.0\"?>" 375 "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">" 376 "<target>")); 377 378 if (cc->gdb_arch_name) { 379 g_ptr_array_add( 380 xml, 381 g_markup_printf_escaped("<architecture>%s</architecture>", 382 cc->gdb_arch_name(cpu))); 383 } 384 g_ptr_array_add( 385 xml, 386 g_markup_printf_escaped("<xi:include href=\"%s\"/>", 387 cc->gdb_core_xml_file)); 388 if (cpu->gdb_regs) { 389 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 390 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 391 g_ptr_array_add( 392 xml, 393 g_markup_printf_escaped("<xi:include href=\"%s\"/>", 394 r->xml)); 395 } 396 } 397 g_ptr_array_add(xml, g_strdup("</target>")); 398 g_ptr_array_add(xml, NULL); 399 400 process->target_xml = g_strjoinv(NULL, (void *)xml->pdata); 401 } 402 return process->target_xml; 403 } 404 /* Is it dynamically generated by the target? */ 405 if (cc->gdb_get_dynamic_xml) { 406 g_autofree char *xmlname = g_strndup(p, len); 407 const char *xml = cc->gdb_get_dynamic_xml(cpu, xmlname); 408 if (xml) { 409 return xml; 410 } 411 } 412 /* Is it one of the encoded gdb-xml/ files? */ 413 for (int i = 0; gdb_static_features[i].xmlname; i++) { 414 const char *name = gdb_static_features[i].xmlname; 415 if ((strncmp(name, p, len) == 0) && 416 strlen(name) == len) { 417 return gdb_static_features[i].xml; 418 } 419 } 420 421 /* failed */ 422 return NULL; 423 } 424 425 void gdb_feature_builder_init(GDBFeatureBuilder *builder, GDBFeature *feature, 426 const char *name, const char *xmlname, 427 int base_reg) 428 { 429 char *header = g_markup_printf_escaped( 430 "<?xml version=\"1.0\"?>" 431 "<!DOCTYPE feature SYSTEM \"gdb-target.dtd\">" 432 "<feature name=\"%s\">", 433 name); 434 435 builder->feature = feature; 436 builder->xml = g_ptr_array_new(); 437 g_ptr_array_add(builder->xml, header); 438 builder->base_reg = base_reg; 439 feature->xmlname = xmlname; 440 feature->num_regs = 0; 441 } 442 443 void gdb_feature_builder_append_tag(const GDBFeatureBuilder *builder, 444 const char *format, ...) 445 { 446 va_list ap; 447 va_start(ap, format); 448 g_ptr_array_add(builder->xml, g_markup_vprintf_escaped(format, ap)); 449 va_end(ap); 450 } 451 452 void gdb_feature_builder_append_reg(const GDBFeatureBuilder *builder, 453 const char *name, 454 int bitsize, 455 int regnum, 456 const char *type, 457 const char *group) 458 { 459 if (builder->feature->num_regs < regnum) { 460 builder->feature->num_regs = regnum; 461 } 462 463 if (group) { 464 gdb_feature_builder_append_tag( 465 builder, 466 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\" group=\"%s\"/>", 467 name, bitsize, builder->base_reg + regnum, type, group); 468 } else { 469 gdb_feature_builder_append_tag( 470 builder, 471 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\"/>", 472 name, bitsize, builder->base_reg + regnum, type); 473 } 474 } 475 476 void gdb_feature_builder_end(const GDBFeatureBuilder *builder) 477 { 478 g_ptr_array_add(builder->xml, (void *)"</feature>"); 479 g_ptr_array_add(builder->xml, NULL); 480 481 builder->feature->xml = g_strjoinv(NULL, (void *)builder->xml->pdata); 482 483 for (guint i = 0; i < builder->xml->len - 2; i++) { 484 g_free(g_ptr_array_index(builder->xml, i)); 485 } 486 487 g_ptr_array_free(builder->xml, TRUE); 488 } 489 490 const GDBFeature *gdb_find_static_feature(const char *xmlname) 491 { 492 const GDBFeature *feature; 493 494 for (feature = gdb_static_features; feature->xmlname; feature++) { 495 if (!strcmp(feature->xmlname, xmlname)) { 496 return feature; 497 } 498 } 499 500 g_assert_not_reached(); 501 } 502 503 static int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg) 504 { 505 CPUClass *cc = CPU_GET_CLASS(cpu); 506 CPUArchState *env = cpu_env(cpu); 507 GDBRegisterState *r; 508 509 if (reg < cc->gdb_num_core_regs) { 510 return cc->gdb_read_register(cpu, buf, reg); 511 } 512 513 if (cpu->gdb_regs) { 514 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 515 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 516 if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) { 517 return r->get_reg(env, buf, reg - r->base_reg); 518 } 519 } 520 } 521 return 0; 522 } 523 524 static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg) 525 { 526 CPUClass *cc = CPU_GET_CLASS(cpu); 527 CPUArchState *env = cpu_env(cpu); 528 GDBRegisterState *r; 529 530 if (reg < cc->gdb_num_core_regs) { 531 return cc->gdb_write_register(cpu, mem_buf, reg); 532 } 533 534 if (cpu->gdb_regs) { 535 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 536 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 537 if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) { 538 return r->set_reg(env, mem_buf, reg - r->base_reg); 539 } 540 } 541 } 542 return 0; 543 } 544 545 void gdb_register_coprocessor(CPUState *cpu, 546 gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg, 547 int num_regs, const char *xml, int g_pos) 548 { 549 GDBRegisterState *s; 550 guint i; 551 552 if (cpu->gdb_regs) { 553 for (i = 0; i < cpu->gdb_regs->len; i++) { 554 /* Check for duplicates. */ 555 s = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 556 if (strcmp(s->xml, xml) == 0) { 557 return; 558 } 559 } 560 } else { 561 cpu->gdb_regs = g_array_new(false, false, sizeof(GDBRegisterState)); 562 i = 0; 563 } 564 565 g_array_set_size(cpu->gdb_regs, i + 1); 566 s = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 567 s->base_reg = cpu->gdb_num_regs; 568 s->num_regs = num_regs; 569 s->get_reg = get_reg; 570 s->set_reg = set_reg; 571 s->xml = xml; 572 573 /* Add to end of list. */ 574 cpu->gdb_num_regs += num_regs; 575 if (g_pos) { 576 if (g_pos != s->base_reg) { 577 error_report("Error: Bad gdb register numbering for '%s', " 578 "expected %d got %d", xml, g_pos, s->base_reg); 579 } else { 580 cpu->gdb_num_g_regs = cpu->gdb_num_regs; 581 } 582 } 583 } 584 585 static void gdb_process_breakpoint_remove_all(GDBProcess *p) 586 { 587 CPUState *cpu = gdb_get_first_cpu_in_process(p); 588 589 while (cpu) { 590 gdb_breakpoint_remove_all(cpu); 591 cpu = gdb_next_cpu_in_process(cpu); 592 } 593 } 594 595 596 static void gdb_set_cpu_pc(vaddr pc) 597 { 598 CPUState *cpu = gdbserver_state.c_cpu; 599 600 cpu_synchronize_state(cpu); 601 cpu_set_pc(cpu, pc); 602 } 603 604 void gdb_append_thread_id(CPUState *cpu, GString *buf) 605 { 606 if (gdbserver_state.multiprocess) { 607 g_string_append_printf(buf, "p%02x.%02x", 608 gdb_get_cpu_pid(cpu), gdb_get_cpu_index(cpu)); 609 } else { 610 g_string_append_printf(buf, "%02x", gdb_get_cpu_index(cpu)); 611 } 612 } 613 614 static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf, 615 uint32_t *pid, uint32_t *tid) 616 { 617 unsigned long p, t; 618 int ret; 619 620 if (*buf == 'p') { 621 buf++; 622 ret = qemu_strtoul(buf, &buf, 16, &p); 623 624 if (ret) { 625 return GDB_READ_THREAD_ERR; 626 } 627 628 /* Skip '.' */ 629 buf++; 630 } else { 631 p = 0; 632 } 633 634 ret = qemu_strtoul(buf, &buf, 16, &t); 635 636 if (ret) { 637 return GDB_READ_THREAD_ERR; 638 } 639 640 *end_buf = buf; 641 642 if (p == -1) { 643 return GDB_ALL_PROCESSES; 644 } 645 646 if (pid) { 647 *pid = p; 648 } 649 650 if (t == -1) { 651 return GDB_ALL_THREADS; 652 } 653 654 if (tid) { 655 *tid = t; 656 } 657 658 return GDB_ONE_THREAD; 659 } 660 661 /** 662 * gdb_handle_vcont - Parses and handles a vCont packet. 663 * returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is 664 * a format error, 0 on success. 665 */ 666 static int gdb_handle_vcont(const char *p) 667 { 668 int res, signal = 0; 669 char cur_action; 670 unsigned long tmp; 671 uint32_t pid, tid; 672 GDBProcess *process; 673 CPUState *cpu; 674 GDBThreadIdKind kind; 675 unsigned int max_cpus = gdb_get_max_cpus(); 676 /* uninitialised CPUs stay 0 */ 677 g_autofree char *newstates = g_new0(char, max_cpus); 678 679 /* mark valid CPUs with 1 */ 680 CPU_FOREACH(cpu) { 681 newstates[cpu->cpu_index] = 1; 682 } 683 684 /* 685 * res keeps track of what error we are returning, with -ENOTSUP meaning 686 * that the command is unknown or unsupported, thus returning an empty 687 * packet, while -EINVAL and -ERANGE cause an E22 packet, due to invalid, 688 * or incorrect parameters passed. 689 */ 690 res = 0; 691 692 /* 693 * target_count and last_target keep track of how many CPUs we are going to 694 * step or resume, and a pointer to the state structure of one of them, 695 * respectively 696 */ 697 int target_count = 0; 698 CPUState *last_target = NULL; 699 700 while (*p) { 701 if (*p++ != ';') { 702 return -ENOTSUP; 703 } 704 705 cur_action = *p++; 706 if (cur_action == 'C' || cur_action == 'S') { 707 cur_action = qemu_tolower(cur_action); 708 res = qemu_strtoul(p, &p, 16, &tmp); 709 if (res) { 710 return res; 711 } 712 signal = gdb_signal_to_target(tmp); 713 } else if (cur_action != 'c' && cur_action != 's') { 714 /* unknown/invalid/unsupported command */ 715 return -ENOTSUP; 716 } 717 718 if (*p == '\0' || *p == ';') { 719 /* 720 * No thread specifier, action is on "all threads". The 721 * specification is unclear regarding the process to act on. We 722 * choose all processes. 723 */ 724 kind = GDB_ALL_PROCESSES; 725 } else if (*p++ == ':') { 726 kind = read_thread_id(p, &p, &pid, &tid); 727 } else { 728 return -ENOTSUP; 729 } 730 731 switch (kind) { 732 case GDB_READ_THREAD_ERR: 733 return -EINVAL; 734 735 case GDB_ALL_PROCESSES: 736 cpu = gdb_first_attached_cpu(); 737 while (cpu) { 738 if (newstates[cpu->cpu_index] == 1) { 739 newstates[cpu->cpu_index] = cur_action; 740 741 target_count++; 742 last_target = cpu; 743 } 744 745 cpu = gdb_next_attached_cpu(cpu); 746 } 747 break; 748 749 case GDB_ALL_THREADS: 750 process = gdb_get_process(pid); 751 752 if (!process->attached) { 753 return -EINVAL; 754 } 755 756 cpu = gdb_get_first_cpu_in_process(process); 757 while (cpu) { 758 if (newstates[cpu->cpu_index] == 1) { 759 newstates[cpu->cpu_index] = cur_action; 760 761 target_count++; 762 last_target = cpu; 763 } 764 765 cpu = gdb_next_cpu_in_process(cpu); 766 } 767 break; 768 769 case GDB_ONE_THREAD: 770 cpu = gdb_get_cpu(pid, tid); 771 772 /* invalid CPU/thread specified */ 773 if (!cpu) { 774 return -EINVAL; 775 } 776 777 /* only use if no previous match occourred */ 778 if (newstates[cpu->cpu_index] == 1) { 779 newstates[cpu->cpu_index] = cur_action; 780 781 target_count++; 782 last_target = cpu; 783 } 784 break; 785 } 786 } 787 788 /* 789 * if we're about to resume a specific set of CPUs/threads, make it so that 790 * in case execution gets interrupted, we can send GDB a stop reply with a 791 * correct value. it doesn't really matter which CPU we tell GDB the signal 792 * happened in (VM pauses stop all of them anyway), so long as it is one of 793 * the ones we resumed/single stepped here. 794 */ 795 if (target_count > 0) { 796 gdbserver_state.c_cpu = last_target; 797 } 798 799 gdbserver_state.signal = signal; 800 gdb_continue_partial(newstates); 801 return res; 802 } 803 804 static const char *cmd_next_param(const char *param, const char delimiter) 805 { 806 static const char all_delimiters[] = ",;:="; 807 char curr_delimiters[2] = {0}; 808 const char *delimiters; 809 810 if (delimiter == '?') { 811 delimiters = all_delimiters; 812 } else if (delimiter == '0') { 813 return strchr(param, '\0'); 814 } else if (delimiter == '.' && *param) { 815 return param + 1; 816 } else { 817 curr_delimiters[0] = delimiter; 818 delimiters = curr_delimiters; 819 } 820 821 param += strcspn(param, delimiters); 822 if (*param) { 823 param++; 824 } 825 return param; 826 } 827 828 static int cmd_parse_params(const char *data, const char *schema, 829 GArray *params) 830 { 831 const char *curr_schema, *curr_data; 832 833 g_assert(schema); 834 g_assert(params->len == 0); 835 836 curr_schema = schema; 837 curr_data = data; 838 while (curr_schema[0] && curr_schema[1] && *curr_data) { 839 GdbCmdVariant this_param; 840 841 switch (curr_schema[0]) { 842 case 'l': 843 if (qemu_strtoul(curr_data, &curr_data, 16, 844 &this_param.val_ul)) { 845 return -EINVAL; 846 } 847 curr_data = cmd_next_param(curr_data, curr_schema[1]); 848 g_array_append_val(params, this_param); 849 break; 850 case 'L': 851 if (qemu_strtou64(curr_data, &curr_data, 16, 852 (uint64_t *)&this_param.val_ull)) { 853 return -EINVAL; 854 } 855 curr_data = cmd_next_param(curr_data, curr_schema[1]); 856 g_array_append_val(params, this_param); 857 break; 858 case 's': 859 this_param.data = curr_data; 860 curr_data = cmd_next_param(curr_data, curr_schema[1]); 861 g_array_append_val(params, this_param); 862 break; 863 case 'o': 864 this_param.opcode = *(uint8_t *)curr_data; 865 curr_data = cmd_next_param(curr_data, curr_schema[1]); 866 g_array_append_val(params, this_param); 867 break; 868 case 't': 869 this_param.thread_id.kind = 870 read_thread_id(curr_data, &curr_data, 871 &this_param.thread_id.pid, 872 &this_param.thread_id.tid); 873 curr_data = cmd_next_param(curr_data, curr_schema[1]); 874 g_array_append_val(params, this_param); 875 break; 876 case '?': 877 curr_data = cmd_next_param(curr_data, curr_schema[1]); 878 break; 879 default: 880 return -EINVAL; 881 } 882 curr_schema += 2; 883 } 884 885 return 0; 886 } 887 888 typedef void (*GdbCmdHandler)(GArray *params, void *user_ctx); 889 890 /* 891 * cmd_startswith -> cmd is compared using startswith 892 * 893 * allow_stop_reply -> true iff the gdbstub can respond to this command with a 894 * "stop reply" packet. The list of commands that accept such response is 895 * defined at the GDB Remote Serial Protocol documentation. see: 896 * https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets. 897 * 898 * schema definitions: 899 * Each schema parameter entry consists of 2 chars, 900 * the first char represents the parameter type handling 901 * the second char represents the delimiter for the next parameter 902 * 903 * Currently supported schema types: 904 * 'l' -> unsigned long (stored in .val_ul) 905 * 'L' -> unsigned long long (stored in .val_ull) 906 * 's' -> string (stored in .data) 907 * 'o' -> single char (stored in .opcode) 908 * 't' -> thread id (stored in .thread_id) 909 * '?' -> skip according to delimiter 910 * 911 * Currently supported delimiters: 912 * '?' -> Stop at any delimiter (",;:=\0") 913 * '0' -> Stop at "\0" 914 * '.' -> Skip 1 char unless reached "\0" 915 * Any other value is treated as the delimiter value itself 916 */ 917 typedef struct GdbCmdParseEntry { 918 GdbCmdHandler handler; 919 const char *cmd; 920 bool cmd_startswith; 921 const char *schema; 922 bool allow_stop_reply; 923 } GdbCmdParseEntry; 924 925 static inline int startswith(const char *string, const char *pattern) 926 { 927 return !strncmp(string, pattern, strlen(pattern)); 928 } 929 930 static int process_string_cmd(const char *data, 931 const GdbCmdParseEntry *cmds, int num_cmds) 932 { 933 int i; 934 g_autoptr(GArray) params = g_array_new(false, true, sizeof(GdbCmdVariant)); 935 936 if (!cmds) { 937 return -1; 938 } 939 940 for (i = 0; i < num_cmds; i++) { 941 const GdbCmdParseEntry *cmd = &cmds[i]; 942 g_assert(cmd->handler && cmd->cmd); 943 944 if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) || 945 (!cmd->cmd_startswith && strcmp(cmd->cmd, data))) { 946 continue; 947 } 948 949 if (cmd->schema) { 950 if (cmd_parse_params(&data[strlen(cmd->cmd)], 951 cmd->schema, params)) { 952 return -1; 953 } 954 } 955 956 gdbserver_state.allow_stop_reply = cmd->allow_stop_reply; 957 cmd->handler(params, NULL); 958 return 0; 959 } 960 961 return -1; 962 } 963 964 static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd) 965 { 966 if (!data) { 967 return; 968 } 969 970 g_string_set_size(gdbserver_state.str_buf, 0); 971 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 972 973 /* In case there was an error during the command parsing we must 974 * send a NULL packet to indicate the command is not supported */ 975 if (process_string_cmd(data, cmd, 1)) { 976 gdb_put_packet(""); 977 } 978 } 979 980 static void handle_detach(GArray *params, void *user_ctx) 981 { 982 GDBProcess *process; 983 uint32_t pid = 1; 984 985 if (gdbserver_state.multiprocess) { 986 if (!params->len) { 987 gdb_put_packet("E22"); 988 return; 989 } 990 991 pid = get_param(params, 0)->val_ul; 992 } 993 994 process = gdb_get_process(pid); 995 gdb_process_breakpoint_remove_all(process); 996 process->attached = false; 997 998 if (pid == gdb_get_cpu_pid(gdbserver_state.c_cpu)) { 999 gdbserver_state.c_cpu = gdb_first_attached_cpu(); 1000 } 1001 1002 if (pid == gdb_get_cpu_pid(gdbserver_state.g_cpu)) { 1003 gdbserver_state.g_cpu = gdb_first_attached_cpu(); 1004 } 1005 1006 if (!gdbserver_state.c_cpu) { 1007 /* No more process attached */ 1008 gdb_disable_syscalls(); 1009 gdb_continue(); 1010 } 1011 gdb_put_packet("OK"); 1012 } 1013 1014 static void handle_thread_alive(GArray *params, void *user_ctx) 1015 { 1016 CPUState *cpu; 1017 1018 if (!params->len) { 1019 gdb_put_packet("E22"); 1020 return; 1021 } 1022 1023 if (get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1024 gdb_put_packet("E22"); 1025 return; 1026 } 1027 1028 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1029 get_param(params, 0)->thread_id.tid); 1030 if (!cpu) { 1031 gdb_put_packet("E22"); 1032 return; 1033 } 1034 1035 gdb_put_packet("OK"); 1036 } 1037 1038 static void handle_continue(GArray *params, void *user_ctx) 1039 { 1040 if (params->len) { 1041 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1042 } 1043 1044 gdbserver_state.signal = 0; 1045 gdb_continue(); 1046 } 1047 1048 static void handle_cont_with_sig(GArray *params, void *user_ctx) 1049 { 1050 unsigned long signal = 0; 1051 1052 /* 1053 * Note: C sig;[addr] is currently unsupported and we simply 1054 * omit the addr parameter 1055 */ 1056 if (params->len) { 1057 signal = get_param(params, 0)->val_ul; 1058 } 1059 1060 gdbserver_state.signal = gdb_signal_to_target(signal); 1061 if (gdbserver_state.signal == -1) { 1062 gdbserver_state.signal = 0; 1063 } 1064 gdb_continue(); 1065 } 1066 1067 static void handle_set_thread(GArray *params, void *user_ctx) 1068 { 1069 CPUState *cpu; 1070 1071 if (params->len != 2) { 1072 gdb_put_packet("E22"); 1073 return; 1074 } 1075 1076 if (get_param(params, 1)->thread_id.kind == GDB_READ_THREAD_ERR) { 1077 gdb_put_packet("E22"); 1078 return; 1079 } 1080 1081 if (get_param(params, 1)->thread_id.kind != GDB_ONE_THREAD) { 1082 gdb_put_packet("OK"); 1083 return; 1084 } 1085 1086 cpu = gdb_get_cpu(get_param(params, 1)->thread_id.pid, 1087 get_param(params, 1)->thread_id.tid); 1088 if (!cpu) { 1089 gdb_put_packet("E22"); 1090 return; 1091 } 1092 1093 /* 1094 * Note: This command is deprecated and modern gdb's will be using the 1095 * vCont command instead. 1096 */ 1097 switch (get_param(params, 0)->opcode) { 1098 case 'c': 1099 gdbserver_state.c_cpu = cpu; 1100 gdb_put_packet("OK"); 1101 break; 1102 case 'g': 1103 gdbserver_state.g_cpu = cpu; 1104 gdb_put_packet("OK"); 1105 break; 1106 default: 1107 gdb_put_packet("E22"); 1108 break; 1109 } 1110 } 1111 1112 static void handle_insert_bp(GArray *params, void *user_ctx) 1113 { 1114 int res; 1115 1116 if (params->len != 3) { 1117 gdb_put_packet("E22"); 1118 return; 1119 } 1120 1121 res = gdb_breakpoint_insert(gdbserver_state.c_cpu, 1122 get_param(params, 0)->val_ul, 1123 get_param(params, 1)->val_ull, 1124 get_param(params, 2)->val_ull); 1125 if (res >= 0) { 1126 gdb_put_packet("OK"); 1127 return; 1128 } else if (res == -ENOSYS) { 1129 gdb_put_packet(""); 1130 return; 1131 } 1132 1133 gdb_put_packet("E22"); 1134 } 1135 1136 static void handle_remove_bp(GArray *params, void *user_ctx) 1137 { 1138 int res; 1139 1140 if (params->len != 3) { 1141 gdb_put_packet("E22"); 1142 return; 1143 } 1144 1145 res = gdb_breakpoint_remove(gdbserver_state.c_cpu, 1146 get_param(params, 0)->val_ul, 1147 get_param(params, 1)->val_ull, 1148 get_param(params, 2)->val_ull); 1149 if (res >= 0) { 1150 gdb_put_packet("OK"); 1151 return; 1152 } else if (res == -ENOSYS) { 1153 gdb_put_packet(""); 1154 return; 1155 } 1156 1157 gdb_put_packet("E22"); 1158 } 1159 1160 /* 1161 * handle_set/get_reg 1162 * 1163 * Older gdb are really dumb, and don't use 'G/g' if 'P/p' is available. 1164 * This works, but can be very slow. Anything new enough to understand 1165 * XML also knows how to use this properly. However to use this we 1166 * need to define a local XML file as well as be talking to a 1167 * reasonably modern gdb. Responding with an empty packet will cause 1168 * the remote gdb to fallback to older methods. 1169 */ 1170 1171 static void handle_set_reg(GArray *params, void *user_ctx) 1172 { 1173 int reg_size; 1174 1175 if (params->len != 2) { 1176 gdb_put_packet("E22"); 1177 return; 1178 } 1179 1180 reg_size = strlen(get_param(params, 1)->data) / 2; 1181 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, reg_size); 1182 gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data, 1183 get_param(params, 0)->val_ull); 1184 gdb_put_packet("OK"); 1185 } 1186 1187 static void handle_get_reg(GArray *params, void *user_ctx) 1188 { 1189 int reg_size; 1190 1191 if (!params->len) { 1192 gdb_put_packet("E14"); 1193 return; 1194 } 1195 1196 reg_size = gdb_read_register(gdbserver_state.g_cpu, 1197 gdbserver_state.mem_buf, 1198 get_param(params, 0)->val_ull); 1199 if (!reg_size) { 1200 gdb_put_packet("E14"); 1201 return; 1202 } else { 1203 g_byte_array_set_size(gdbserver_state.mem_buf, reg_size); 1204 } 1205 1206 gdb_memtohex(gdbserver_state.str_buf, 1207 gdbserver_state.mem_buf->data, reg_size); 1208 gdb_put_strbuf(); 1209 } 1210 1211 static void handle_write_mem(GArray *params, void *user_ctx) 1212 { 1213 if (params->len != 3) { 1214 gdb_put_packet("E22"); 1215 return; 1216 } 1217 1218 /* gdb_hextomem() reads 2*len bytes */ 1219 if (get_param(params, 1)->val_ull > 1220 strlen(get_param(params, 2)->data) / 2) { 1221 gdb_put_packet("E22"); 1222 return; 1223 } 1224 1225 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 2)->data, 1226 get_param(params, 1)->val_ull); 1227 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1228 get_param(params, 0)->val_ull, 1229 gdbserver_state.mem_buf->data, 1230 gdbserver_state.mem_buf->len, true)) { 1231 gdb_put_packet("E14"); 1232 return; 1233 } 1234 1235 gdb_put_packet("OK"); 1236 } 1237 1238 static void handle_read_mem(GArray *params, void *user_ctx) 1239 { 1240 if (params->len != 2) { 1241 gdb_put_packet("E22"); 1242 return; 1243 } 1244 1245 /* gdb_memtohex() doubles the required space */ 1246 if (get_param(params, 1)->val_ull > MAX_PACKET_LENGTH / 2) { 1247 gdb_put_packet("E22"); 1248 return; 1249 } 1250 1251 g_byte_array_set_size(gdbserver_state.mem_buf, 1252 get_param(params, 1)->val_ull); 1253 1254 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1255 get_param(params, 0)->val_ull, 1256 gdbserver_state.mem_buf->data, 1257 gdbserver_state.mem_buf->len, false)) { 1258 gdb_put_packet("E14"); 1259 return; 1260 } 1261 1262 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, 1263 gdbserver_state.mem_buf->len); 1264 gdb_put_strbuf(); 1265 } 1266 1267 static void handle_write_all_regs(GArray *params, void *user_ctx) 1268 { 1269 int reg_id; 1270 size_t len; 1271 uint8_t *registers; 1272 int reg_size; 1273 1274 if (!params->len) { 1275 return; 1276 } 1277 1278 cpu_synchronize_state(gdbserver_state.g_cpu); 1279 len = strlen(get_param(params, 0)->data) / 2; 1280 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 0)->data, len); 1281 registers = gdbserver_state.mem_buf->data; 1282 for (reg_id = 0; 1283 reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0; 1284 reg_id++) { 1285 reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id); 1286 len -= reg_size; 1287 registers += reg_size; 1288 } 1289 gdb_put_packet("OK"); 1290 } 1291 1292 static void handle_read_all_regs(GArray *params, void *user_ctx) 1293 { 1294 int reg_id; 1295 size_t len; 1296 1297 cpu_synchronize_state(gdbserver_state.g_cpu); 1298 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 1299 len = 0; 1300 for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) { 1301 len += gdb_read_register(gdbserver_state.g_cpu, 1302 gdbserver_state.mem_buf, 1303 reg_id); 1304 } 1305 g_assert(len == gdbserver_state.mem_buf->len); 1306 1307 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len); 1308 gdb_put_strbuf(); 1309 } 1310 1311 1312 static void handle_step(GArray *params, void *user_ctx) 1313 { 1314 if (params->len) { 1315 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1316 } 1317 1318 cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags); 1319 gdb_continue(); 1320 } 1321 1322 static void handle_backward(GArray *params, void *user_ctx) 1323 { 1324 if (!gdb_can_reverse()) { 1325 gdb_put_packet("E22"); 1326 } 1327 if (params->len == 1) { 1328 switch (get_param(params, 0)->opcode) { 1329 case 's': 1330 if (replay_reverse_step()) { 1331 gdb_continue(); 1332 } else { 1333 gdb_put_packet("E14"); 1334 } 1335 return; 1336 case 'c': 1337 if (replay_reverse_continue()) { 1338 gdb_continue(); 1339 } else { 1340 gdb_put_packet("E14"); 1341 } 1342 return; 1343 } 1344 } 1345 1346 /* Default invalid command */ 1347 gdb_put_packet(""); 1348 } 1349 1350 static void handle_v_cont_query(GArray *params, void *user_ctx) 1351 { 1352 gdb_put_packet("vCont;c;C;s;S"); 1353 } 1354 1355 static void handle_v_cont(GArray *params, void *user_ctx) 1356 { 1357 int res; 1358 1359 if (!params->len) { 1360 return; 1361 } 1362 1363 res = gdb_handle_vcont(get_param(params, 0)->data); 1364 if ((res == -EINVAL) || (res == -ERANGE)) { 1365 gdb_put_packet("E22"); 1366 } else if (res) { 1367 gdb_put_packet(""); 1368 } 1369 } 1370 1371 static void handle_v_attach(GArray *params, void *user_ctx) 1372 { 1373 GDBProcess *process; 1374 CPUState *cpu; 1375 1376 g_string_assign(gdbserver_state.str_buf, "E22"); 1377 if (!params->len) { 1378 goto cleanup; 1379 } 1380 1381 process = gdb_get_process(get_param(params, 0)->val_ul); 1382 if (!process) { 1383 goto cleanup; 1384 } 1385 1386 cpu = gdb_get_first_cpu_in_process(process); 1387 if (!cpu) { 1388 goto cleanup; 1389 } 1390 1391 process->attached = true; 1392 gdbserver_state.g_cpu = cpu; 1393 gdbserver_state.c_cpu = cpu; 1394 1395 if (gdbserver_state.allow_stop_reply) { 1396 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1397 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1398 g_string_append_c(gdbserver_state.str_buf, ';'); 1399 gdbserver_state.allow_stop_reply = false; 1400 cleanup: 1401 gdb_put_strbuf(); 1402 } 1403 } 1404 1405 static void handle_v_kill(GArray *params, void *user_ctx) 1406 { 1407 /* Kill the target */ 1408 gdb_put_packet("OK"); 1409 error_report("QEMU: Terminated via GDBstub"); 1410 gdb_exit(0); 1411 gdb_qemu_exit(0); 1412 } 1413 1414 static const GdbCmdParseEntry gdb_v_commands_table[] = { 1415 /* Order is important if has same prefix */ 1416 { 1417 .handler = handle_v_cont_query, 1418 .cmd = "Cont?", 1419 .cmd_startswith = 1 1420 }, 1421 { 1422 .handler = handle_v_cont, 1423 .cmd = "Cont", 1424 .cmd_startswith = 1, 1425 .allow_stop_reply = true, 1426 .schema = "s0" 1427 }, 1428 { 1429 .handler = handle_v_attach, 1430 .cmd = "Attach;", 1431 .cmd_startswith = 1, 1432 .allow_stop_reply = true, 1433 .schema = "l0" 1434 }, 1435 { 1436 .handler = handle_v_kill, 1437 .cmd = "Kill;", 1438 .cmd_startswith = 1 1439 }, 1440 #ifdef CONFIG_USER_ONLY 1441 /* 1442 * Host I/O Packets. See [1] for details. 1443 * [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html 1444 */ 1445 { 1446 .handler = gdb_handle_v_file_open, 1447 .cmd = "File:open:", 1448 .cmd_startswith = 1, 1449 .schema = "s,L,L0" 1450 }, 1451 { 1452 .handler = gdb_handle_v_file_close, 1453 .cmd = "File:close:", 1454 .cmd_startswith = 1, 1455 .schema = "l0" 1456 }, 1457 { 1458 .handler = gdb_handle_v_file_pread, 1459 .cmd = "File:pread:", 1460 .cmd_startswith = 1, 1461 .schema = "l,L,L0" 1462 }, 1463 { 1464 .handler = gdb_handle_v_file_readlink, 1465 .cmd = "File:readlink:", 1466 .cmd_startswith = 1, 1467 .schema = "s0" 1468 }, 1469 #endif 1470 }; 1471 1472 static void handle_v_commands(GArray *params, void *user_ctx) 1473 { 1474 if (!params->len) { 1475 return; 1476 } 1477 1478 if (process_string_cmd(get_param(params, 0)->data, 1479 gdb_v_commands_table, 1480 ARRAY_SIZE(gdb_v_commands_table))) { 1481 gdb_put_packet(""); 1482 } 1483 } 1484 1485 static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx) 1486 { 1487 g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE); 1488 1489 if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) { 1490 g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x", 1491 SSTEP_NOIRQ); 1492 } 1493 1494 if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) { 1495 g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x", 1496 SSTEP_NOTIMER); 1497 } 1498 1499 gdb_put_strbuf(); 1500 } 1501 1502 static void handle_set_qemu_sstep(GArray *params, void *user_ctx) 1503 { 1504 int new_sstep_flags; 1505 1506 if (!params->len) { 1507 return; 1508 } 1509 1510 new_sstep_flags = get_param(params, 0)->val_ul; 1511 1512 if (new_sstep_flags & ~gdbserver_state.supported_sstep_flags) { 1513 gdb_put_packet("E22"); 1514 return; 1515 } 1516 1517 gdbserver_state.sstep_flags = new_sstep_flags; 1518 gdb_put_packet("OK"); 1519 } 1520 1521 static void handle_query_qemu_sstep(GArray *params, void *user_ctx) 1522 { 1523 g_string_printf(gdbserver_state.str_buf, "0x%x", 1524 gdbserver_state.sstep_flags); 1525 gdb_put_strbuf(); 1526 } 1527 1528 static void handle_query_curr_tid(GArray *params, void *user_ctx) 1529 { 1530 CPUState *cpu; 1531 GDBProcess *process; 1532 1533 /* 1534 * "Current thread" remains vague in the spec, so always return 1535 * the first thread of the current process (gdb returns the 1536 * first thread). 1537 */ 1538 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1539 cpu = gdb_get_first_cpu_in_process(process); 1540 g_string_assign(gdbserver_state.str_buf, "QC"); 1541 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1542 gdb_put_strbuf(); 1543 } 1544 1545 static void handle_query_threads(GArray *params, void *user_ctx) 1546 { 1547 if (!gdbserver_state.query_cpu) { 1548 gdb_put_packet("l"); 1549 return; 1550 } 1551 1552 g_string_assign(gdbserver_state.str_buf, "m"); 1553 gdb_append_thread_id(gdbserver_state.query_cpu, gdbserver_state.str_buf); 1554 gdb_put_strbuf(); 1555 gdbserver_state.query_cpu = gdb_next_attached_cpu(gdbserver_state.query_cpu); 1556 } 1557 1558 static void handle_query_first_threads(GArray *params, void *user_ctx) 1559 { 1560 gdbserver_state.query_cpu = gdb_first_attached_cpu(); 1561 handle_query_threads(params, user_ctx); 1562 } 1563 1564 static void handle_query_thread_extra(GArray *params, void *user_ctx) 1565 { 1566 g_autoptr(GString) rs = g_string_new(NULL); 1567 CPUState *cpu; 1568 1569 if (!params->len || 1570 get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1571 gdb_put_packet("E22"); 1572 return; 1573 } 1574 1575 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1576 get_param(params, 0)->thread_id.tid); 1577 if (!cpu) { 1578 return; 1579 } 1580 1581 cpu_synchronize_state(cpu); 1582 1583 if (gdbserver_state.multiprocess && (gdbserver_state.process_num > 1)) { 1584 /* Print the CPU model and name in multiprocess mode */ 1585 ObjectClass *oc = object_get_class(OBJECT(cpu)); 1586 const char *cpu_model = object_class_get_name(oc); 1587 const char *cpu_name = 1588 object_get_canonical_path_component(OBJECT(cpu)); 1589 g_string_printf(rs, "%s %s [%s]", cpu_model, cpu_name, 1590 cpu->halted ? "halted " : "running"); 1591 } else { 1592 g_string_printf(rs, "CPU#%d [%s]", cpu->cpu_index, 1593 cpu->halted ? "halted " : "running"); 1594 } 1595 trace_gdbstub_op_extra_info(rs->str); 1596 gdb_memtohex(gdbserver_state.str_buf, (uint8_t *)rs->str, rs->len); 1597 gdb_put_strbuf(); 1598 } 1599 1600 static void handle_query_supported(GArray *params, void *user_ctx) 1601 { 1602 CPUClass *cc; 1603 1604 g_string_printf(gdbserver_state.str_buf, "PacketSize=%x", MAX_PACKET_LENGTH); 1605 cc = CPU_GET_CLASS(first_cpu); 1606 if (cc->gdb_core_xml_file) { 1607 g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+"); 1608 } 1609 1610 if (gdb_can_reverse()) { 1611 g_string_append(gdbserver_state.str_buf, 1612 ";ReverseStep+;ReverseContinue+"); 1613 } 1614 1615 #if defined(CONFIG_USER_ONLY) 1616 #if defined(CONFIG_LINUX) 1617 if (gdbserver_state.c_cpu->opaque) { 1618 g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+"); 1619 } 1620 g_string_append(gdbserver_state.str_buf, ";QCatchSyscalls+"); 1621 #endif 1622 g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+"); 1623 #endif 1624 1625 if (params->len && 1626 strstr(get_param(params, 0)->data, "multiprocess+")) { 1627 gdbserver_state.multiprocess = true; 1628 } 1629 1630 g_string_append(gdbserver_state.str_buf, ";vContSupported+;multiprocess+"); 1631 gdb_put_strbuf(); 1632 } 1633 1634 static void handle_query_xfer_features(GArray *params, void *user_ctx) 1635 { 1636 GDBProcess *process; 1637 CPUClass *cc; 1638 unsigned long len, total_len, addr; 1639 const char *xml; 1640 const char *p; 1641 1642 if (params->len < 3) { 1643 gdb_put_packet("E22"); 1644 return; 1645 } 1646 1647 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1648 cc = CPU_GET_CLASS(gdbserver_state.g_cpu); 1649 if (!cc->gdb_core_xml_file) { 1650 gdb_put_packet(""); 1651 return; 1652 } 1653 1654 p = get_param(params, 0)->data; 1655 xml = get_feature_xml(p, &p, process); 1656 if (!xml) { 1657 gdb_put_packet("E00"); 1658 return; 1659 } 1660 1661 addr = get_param(params, 1)->val_ul; 1662 len = get_param(params, 2)->val_ul; 1663 total_len = strlen(xml); 1664 if (addr > total_len) { 1665 gdb_put_packet("E00"); 1666 return; 1667 } 1668 1669 if (len > (MAX_PACKET_LENGTH - 5) / 2) { 1670 len = (MAX_PACKET_LENGTH - 5) / 2; 1671 } 1672 1673 if (len < total_len - addr) { 1674 g_string_assign(gdbserver_state.str_buf, "m"); 1675 gdb_memtox(gdbserver_state.str_buf, xml + addr, len); 1676 } else { 1677 g_string_assign(gdbserver_state.str_buf, "l"); 1678 gdb_memtox(gdbserver_state.str_buf, xml + addr, total_len - addr); 1679 } 1680 1681 gdb_put_packet_binary(gdbserver_state.str_buf->str, 1682 gdbserver_state.str_buf->len, true); 1683 } 1684 1685 static void handle_query_qemu_supported(GArray *params, void *user_ctx) 1686 { 1687 g_string_printf(gdbserver_state.str_buf, "sstepbits;sstep"); 1688 #ifndef CONFIG_USER_ONLY 1689 g_string_append(gdbserver_state.str_buf, ";PhyMemMode"); 1690 #endif 1691 gdb_put_strbuf(); 1692 } 1693 1694 static const GdbCmdParseEntry gdb_gen_query_set_common_table[] = { 1695 /* Order is important if has same prefix */ 1696 { 1697 .handler = handle_query_qemu_sstepbits, 1698 .cmd = "qemu.sstepbits", 1699 }, 1700 { 1701 .handler = handle_query_qemu_sstep, 1702 .cmd = "qemu.sstep", 1703 }, 1704 { 1705 .handler = handle_set_qemu_sstep, 1706 .cmd = "qemu.sstep=", 1707 .cmd_startswith = 1, 1708 .schema = "l0" 1709 }, 1710 }; 1711 1712 static const GdbCmdParseEntry gdb_gen_query_table[] = { 1713 { 1714 .handler = handle_query_curr_tid, 1715 .cmd = "C", 1716 }, 1717 { 1718 .handler = handle_query_threads, 1719 .cmd = "sThreadInfo", 1720 }, 1721 { 1722 .handler = handle_query_first_threads, 1723 .cmd = "fThreadInfo", 1724 }, 1725 { 1726 .handler = handle_query_thread_extra, 1727 .cmd = "ThreadExtraInfo,", 1728 .cmd_startswith = 1, 1729 .schema = "t0" 1730 }, 1731 #ifdef CONFIG_USER_ONLY 1732 { 1733 .handler = gdb_handle_query_offsets, 1734 .cmd = "Offsets", 1735 }, 1736 #else 1737 { 1738 .handler = gdb_handle_query_rcmd, 1739 .cmd = "Rcmd,", 1740 .cmd_startswith = 1, 1741 .schema = "s0" 1742 }, 1743 #endif 1744 { 1745 .handler = handle_query_supported, 1746 .cmd = "Supported:", 1747 .cmd_startswith = 1, 1748 .schema = "s0" 1749 }, 1750 { 1751 .handler = handle_query_supported, 1752 .cmd = "Supported", 1753 .schema = "s0" 1754 }, 1755 { 1756 .handler = handle_query_xfer_features, 1757 .cmd = "Xfer:features:read:", 1758 .cmd_startswith = 1, 1759 .schema = "s:l,l0" 1760 }, 1761 #if defined(CONFIG_USER_ONLY) 1762 #if defined(CONFIG_LINUX) 1763 { 1764 .handler = gdb_handle_query_xfer_auxv, 1765 .cmd = "Xfer:auxv:read::", 1766 .cmd_startswith = 1, 1767 .schema = "l,l0" 1768 }, 1769 #endif 1770 { 1771 .handler = gdb_handle_query_xfer_exec_file, 1772 .cmd = "Xfer:exec-file:read:", 1773 .cmd_startswith = 1, 1774 .schema = "l:l,l0" 1775 }, 1776 #endif 1777 { 1778 .handler = gdb_handle_query_attached, 1779 .cmd = "Attached:", 1780 .cmd_startswith = 1 1781 }, 1782 { 1783 .handler = gdb_handle_query_attached, 1784 .cmd = "Attached", 1785 }, 1786 { 1787 .handler = handle_query_qemu_supported, 1788 .cmd = "qemu.Supported", 1789 }, 1790 #ifndef CONFIG_USER_ONLY 1791 { 1792 .handler = gdb_handle_query_qemu_phy_mem_mode, 1793 .cmd = "qemu.PhyMemMode", 1794 }, 1795 #endif 1796 }; 1797 1798 static const GdbCmdParseEntry gdb_gen_set_table[] = { 1799 /* Order is important if has same prefix */ 1800 { 1801 .handler = handle_set_qemu_sstep, 1802 .cmd = "qemu.sstep:", 1803 .cmd_startswith = 1, 1804 .schema = "l0" 1805 }, 1806 #ifndef CONFIG_USER_ONLY 1807 { 1808 .handler = gdb_handle_set_qemu_phy_mem_mode, 1809 .cmd = "qemu.PhyMemMode:", 1810 .cmd_startswith = 1, 1811 .schema = "l0" 1812 }, 1813 #endif 1814 #if defined(CONFIG_USER_ONLY) 1815 { 1816 .handler = gdb_handle_set_catch_syscalls, 1817 .cmd = "CatchSyscalls:", 1818 .cmd_startswith = 1, 1819 .schema = "s0", 1820 }, 1821 #endif 1822 }; 1823 1824 static void handle_gen_query(GArray *params, void *user_ctx) 1825 { 1826 if (!params->len) { 1827 return; 1828 } 1829 1830 if (!process_string_cmd(get_param(params, 0)->data, 1831 gdb_gen_query_set_common_table, 1832 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1833 return; 1834 } 1835 1836 if (process_string_cmd(get_param(params, 0)->data, 1837 gdb_gen_query_table, 1838 ARRAY_SIZE(gdb_gen_query_table))) { 1839 gdb_put_packet(""); 1840 } 1841 } 1842 1843 static void handle_gen_set(GArray *params, void *user_ctx) 1844 { 1845 if (!params->len) { 1846 return; 1847 } 1848 1849 if (!process_string_cmd(get_param(params, 0)->data, 1850 gdb_gen_query_set_common_table, 1851 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1852 return; 1853 } 1854 1855 if (process_string_cmd(get_param(params, 0)->data, 1856 gdb_gen_set_table, 1857 ARRAY_SIZE(gdb_gen_set_table))) { 1858 gdb_put_packet(""); 1859 } 1860 } 1861 1862 static void handle_target_halt(GArray *params, void *user_ctx) 1863 { 1864 if (gdbserver_state.allow_stop_reply) { 1865 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1866 gdb_append_thread_id(gdbserver_state.c_cpu, gdbserver_state.str_buf); 1867 g_string_append_c(gdbserver_state.str_buf, ';'); 1868 gdb_put_strbuf(); 1869 gdbserver_state.allow_stop_reply = false; 1870 } 1871 /* 1872 * Remove all the breakpoints when this query is issued, 1873 * because gdb is doing an initial connect and the state 1874 * should be cleaned up. 1875 */ 1876 gdb_breakpoint_remove_all(gdbserver_state.c_cpu); 1877 } 1878 1879 static int gdb_handle_packet(const char *line_buf) 1880 { 1881 const GdbCmdParseEntry *cmd_parser = NULL; 1882 1883 trace_gdbstub_io_command(line_buf); 1884 1885 switch (line_buf[0]) { 1886 case '!': 1887 gdb_put_packet("OK"); 1888 break; 1889 case '?': 1890 { 1891 static const GdbCmdParseEntry target_halted_cmd_desc = { 1892 .handler = handle_target_halt, 1893 .cmd = "?", 1894 .cmd_startswith = 1, 1895 .allow_stop_reply = true, 1896 }; 1897 cmd_parser = &target_halted_cmd_desc; 1898 } 1899 break; 1900 case 'c': 1901 { 1902 static const GdbCmdParseEntry continue_cmd_desc = { 1903 .handler = handle_continue, 1904 .cmd = "c", 1905 .cmd_startswith = 1, 1906 .allow_stop_reply = true, 1907 .schema = "L0" 1908 }; 1909 cmd_parser = &continue_cmd_desc; 1910 } 1911 break; 1912 case 'C': 1913 { 1914 static const GdbCmdParseEntry cont_with_sig_cmd_desc = { 1915 .handler = handle_cont_with_sig, 1916 .cmd = "C", 1917 .cmd_startswith = 1, 1918 .allow_stop_reply = true, 1919 .schema = "l0" 1920 }; 1921 cmd_parser = &cont_with_sig_cmd_desc; 1922 } 1923 break; 1924 case 'v': 1925 { 1926 static const GdbCmdParseEntry v_cmd_desc = { 1927 .handler = handle_v_commands, 1928 .cmd = "v", 1929 .cmd_startswith = 1, 1930 .schema = "s0" 1931 }; 1932 cmd_parser = &v_cmd_desc; 1933 } 1934 break; 1935 case 'k': 1936 /* Kill the target */ 1937 error_report("QEMU: Terminated via GDBstub"); 1938 gdb_exit(0); 1939 gdb_qemu_exit(0); 1940 break; 1941 case 'D': 1942 { 1943 static const GdbCmdParseEntry detach_cmd_desc = { 1944 .handler = handle_detach, 1945 .cmd = "D", 1946 .cmd_startswith = 1, 1947 .schema = "?.l0" 1948 }; 1949 cmd_parser = &detach_cmd_desc; 1950 } 1951 break; 1952 case 's': 1953 { 1954 static const GdbCmdParseEntry step_cmd_desc = { 1955 .handler = handle_step, 1956 .cmd = "s", 1957 .cmd_startswith = 1, 1958 .allow_stop_reply = true, 1959 .schema = "L0" 1960 }; 1961 cmd_parser = &step_cmd_desc; 1962 } 1963 break; 1964 case 'b': 1965 { 1966 static const GdbCmdParseEntry backward_cmd_desc = { 1967 .handler = handle_backward, 1968 .cmd = "b", 1969 .cmd_startswith = 1, 1970 .allow_stop_reply = true, 1971 .schema = "o0" 1972 }; 1973 cmd_parser = &backward_cmd_desc; 1974 } 1975 break; 1976 case 'F': 1977 { 1978 static const GdbCmdParseEntry file_io_cmd_desc = { 1979 .handler = gdb_handle_file_io, 1980 .cmd = "F", 1981 .cmd_startswith = 1, 1982 .schema = "L,L,o0" 1983 }; 1984 cmd_parser = &file_io_cmd_desc; 1985 } 1986 break; 1987 case 'g': 1988 { 1989 static const GdbCmdParseEntry read_all_regs_cmd_desc = { 1990 .handler = handle_read_all_regs, 1991 .cmd = "g", 1992 .cmd_startswith = 1 1993 }; 1994 cmd_parser = &read_all_regs_cmd_desc; 1995 } 1996 break; 1997 case 'G': 1998 { 1999 static const GdbCmdParseEntry write_all_regs_cmd_desc = { 2000 .handler = handle_write_all_regs, 2001 .cmd = "G", 2002 .cmd_startswith = 1, 2003 .schema = "s0" 2004 }; 2005 cmd_parser = &write_all_regs_cmd_desc; 2006 } 2007 break; 2008 case 'm': 2009 { 2010 static const GdbCmdParseEntry read_mem_cmd_desc = { 2011 .handler = handle_read_mem, 2012 .cmd = "m", 2013 .cmd_startswith = 1, 2014 .schema = "L,L0" 2015 }; 2016 cmd_parser = &read_mem_cmd_desc; 2017 } 2018 break; 2019 case 'M': 2020 { 2021 static const GdbCmdParseEntry write_mem_cmd_desc = { 2022 .handler = handle_write_mem, 2023 .cmd = "M", 2024 .cmd_startswith = 1, 2025 .schema = "L,L:s0" 2026 }; 2027 cmd_parser = &write_mem_cmd_desc; 2028 } 2029 break; 2030 case 'p': 2031 { 2032 static const GdbCmdParseEntry get_reg_cmd_desc = { 2033 .handler = handle_get_reg, 2034 .cmd = "p", 2035 .cmd_startswith = 1, 2036 .schema = "L0" 2037 }; 2038 cmd_parser = &get_reg_cmd_desc; 2039 } 2040 break; 2041 case 'P': 2042 { 2043 static const GdbCmdParseEntry set_reg_cmd_desc = { 2044 .handler = handle_set_reg, 2045 .cmd = "P", 2046 .cmd_startswith = 1, 2047 .schema = "L?s0" 2048 }; 2049 cmd_parser = &set_reg_cmd_desc; 2050 } 2051 break; 2052 case 'Z': 2053 { 2054 static const GdbCmdParseEntry insert_bp_cmd_desc = { 2055 .handler = handle_insert_bp, 2056 .cmd = "Z", 2057 .cmd_startswith = 1, 2058 .schema = "l?L?L0" 2059 }; 2060 cmd_parser = &insert_bp_cmd_desc; 2061 } 2062 break; 2063 case 'z': 2064 { 2065 static const GdbCmdParseEntry remove_bp_cmd_desc = { 2066 .handler = handle_remove_bp, 2067 .cmd = "z", 2068 .cmd_startswith = 1, 2069 .schema = "l?L?L0" 2070 }; 2071 cmd_parser = &remove_bp_cmd_desc; 2072 } 2073 break; 2074 case 'H': 2075 { 2076 static const GdbCmdParseEntry set_thread_cmd_desc = { 2077 .handler = handle_set_thread, 2078 .cmd = "H", 2079 .cmd_startswith = 1, 2080 .schema = "o.t0" 2081 }; 2082 cmd_parser = &set_thread_cmd_desc; 2083 } 2084 break; 2085 case 'T': 2086 { 2087 static const GdbCmdParseEntry thread_alive_cmd_desc = { 2088 .handler = handle_thread_alive, 2089 .cmd = "T", 2090 .cmd_startswith = 1, 2091 .schema = "t0" 2092 }; 2093 cmd_parser = &thread_alive_cmd_desc; 2094 } 2095 break; 2096 case 'q': 2097 { 2098 static const GdbCmdParseEntry gen_query_cmd_desc = { 2099 .handler = handle_gen_query, 2100 .cmd = "q", 2101 .cmd_startswith = 1, 2102 .schema = "s0" 2103 }; 2104 cmd_parser = &gen_query_cmd_desc; 2105 } 2106 break; 2107 case 'Q': 2108 { 2109 static const GdbCmdParseEntry gen_set_cmd_desc = { 2110 .handler = handle_gen_set, 2111 .cmd = "Q", 2112 .cmd_startswith = 1, 2113 .schema = "s0" 2114 }; 2115 cmd_parser = &gen_set_cmd_desc; 2116 } 2117 break; 2118 default: 2119 /* put empty packet */ 2120 gdb_put_packet(""); 2121 break; 2122 } 2123 2124 if (cmd_parser) { 2125 run_cmd_parser(line_buf, cmd_parser); 2126 } 2127 2128 return RS_IDLE; 2129 } 2130 2131 void gdb_set_stop_cpu(CPUState *cpu) 2132 { 2133 GDBProcess *p = gdb_get_cpu_process(cpu); 2134 2135 if (!p->attached) { 2136 /* 2137 * Having a stop CPU corresponding to a process that is not attached 2138 * confuses GDB. So we ignore the request. 2139 */ 2140 return; 2141 } 2142 2143 gdbserver_state.c_cpu = cpu; 2144 gdbserver_state.g_cpu = cpu; 2145 } 2146 2147 void gdb_read_byte(uint8_t ch) 2148 { 2149 uint8_t reply; 2150 2151 gdbserver_state.allow_stop_reply = false; 2152 #ifndef CONFIG_USER_ONLY 2153 if (gdbserver_state.last_packet->len) { 2154 /* Waiting for a response to the last packet. If we see the start 2155 of a new command then abandon the previous response. */ 2156 if (ch == '-') { 2157 trace_gdbstub_err_got_nack(); 2158 gdb_put_buffer(gdbserver_state.last_packet->data, 2159 gdbserver_state.last_packet->len); 2160 } else if (ch == '+') { 2161 trace_gdbstub_io_got_ack(); 2162 } else { 2163 trace_gdbstub_io_got_unexpected(ch); 2164 } 2165 2166 if (ch == '+' || ch == '$') { 2167 g_byte_array_set_size(gdbserver_state.last_packet, 0); 2168 } 2169 if (ch != '$') 2170 return; 2171 } 2172 if (runstate_is_running()) { 2173 /* 2174 * When the CPU is running, we cannot do anything except stop 2175 * it when receiving a char. This is expected on a Ctrl-C in the 2176 * gdb client. Because we are in all-stop mode, gdb sends a 2177 * 0x03 byte which is not a usual packet, so we handle it specially 2178 * here, but it does expect a stop reply. 2179 */ 2180 if (ch != 0x03) { 2181 trace_gdbstub_err_unexpected_runpkt(ch); 2182 } else { 2183 gdbserver_state.allow_stop_reply = true; 2184 } 2185 vm_stop(RUN_STATE_PAUSED); 2186 } else 2187 #endif 2188 { 2189 switch(gdbserver_state.state) { 2190 case RS_IDLE: 2191 if (ch == '$') { 2192 /* start of command packet */ 2193 gdbserver_state.line_buf_index = 0; 2194 gdbserver_state.line_sum = 0; 2195 gdbserver_state.state = RS_GETLINE; 2196 } else if (ch == '+') { 2197 /* 2198 * do nothing, gdb may preemptively send out ACKs on 2199 * initial connection 2200 */ 2201 } else { 2202 trace_gdbstub_err_garbage(ch); 2203 } 2204 break; 2205 case RS_GETLINE: 2206 if (ch == '}') { 2207 /* start escape sequence */ 2208 gdbserver_state.state = RS_GETLINE_ESC; 2209 gdbserver_state.line_sum += ch; 2210 } else if (ch == '*') { 2211 /* start run length encoding sequence */ 2212 gdbserver_state.state = RS_GETLINE_RLE; 2213 gdbserver_state.line_sum += ch; 2214 } else if (ch == '#') { 2215 /* end of command, start of checksum*/ 2216 gdbserver_state.state = RS_CHKSUM1; 2217 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2218 trace_gdbstub_err_overrun(); 2219 gdbserver_state.state = RS_IDLE; 2220 } else { 2221 /* unescaped command character */ 2222 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch; 2223 gdbserver_state.line_sum += ch; 2224 } 2225 break; 2226 case RS_GETLINE_ESC: 2227 if (ch == '#') { 2228 /* unexpected end of command in escape sequence */ 2229 gdbserver_state.state = RS_CHKSUM1; 2230 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2231 /* command buffer overrun */ 2232 trace_gdbstub_err_overrun(); 2233 gdbserver_state.state = RS_IDLE; 2234 } else { 2235 /* parse escaped character and leave escape state */ 2236 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch ^ 0x20; 2237 gdbserver_state.line_sum += ch; 2238 gdbserver_state.state = RS_GETLINE; 2239 } 2240 break; 2241 case RS_GETLINE_RLE: 2242 /* 2243 * Run-length encoding is explained in "Debugging with GDB / 2244 * Appendix E GDB Remote Serial Protocol / Overview". 2245 */ 2246 if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) { 2247 /* invalid RLE count encoding */ 2248 trace_gdbstub_err_invalid_repeat(ch); 2249 gdbserver_state.state = RS_GETLINE; 2250 } else { 2251 /* decode repeat length */ 2252 int repeat = ch - ' ' + 3; 2253 if (gdbserver_state.line_buf_index + repeat >= sizeof(gdbserver_state.line_buf) - 1) { 2254 /* that many repeats would overrun the command buffer */ 2255 trace_gdbstub_err_overrun(); 2256 gdbserver_state.state = RS_IDLE; 2257 } else if (gdbserver_state.line_buf_index < 1) { 2258 /* got a repeat but we have nothing to repeat */ 2259 trace_gdbstub_err_invalid_rle(); 2260 gdbserver_state.state = RS_GETLINE; 2261 } else { 2262 /* repeat the last character */ 2263 memset(gdbserver_state.line_buf + gdbserver_state.line_buf_index, 2264 gdbserver_state.line_buf[gdbserver_state.line_buf_index - 1], repeat); 2265 gdbserver_state.line_buf_index += repeat; 2266 gdbserver_state.line_sum += ch; 2267 gdbserver_state.state = RS_GETLINE; 2268 } 2269 } 2270 break; 2271 case RS_CHKSUM1: 2272 /* get high hex digit of checksum */ 2273 if (!isxdigit(ch)) { 2274 trace_gdbstub_err_checksum_invalid(ch); 2275 gdbserver_state.state = RS_GETLINE; 2276 break; 2277 } 2278 gdbserver_state.line_buf[gdbserver_state.line_buf_index] = '\0'; 2279 gdbserver_state.line_csum = fromhex(ch) << 4; 2280 gdbserver_state.state = RS_CHKSUM2; 2281 break; 2282 case RS_CHKSUM2: 2283 /* get low hex digit of checksum */ 2284 if (!isxdigit(ch)) { 2285 trace_gdbstub_err_checksum_invalid(ch); 2286 gdbserver_state.state = RS_GETLINE; 2287 break; 2288 } 2289 gdbserver_state.line_csum |= fromhex(ch); 2290 2291 if (gdbserver_state.line_csum != (gdbserver_state.line_sum & 0xff)) { 2292 trace_gdbstub_err_checksum_incorrect(gdbserver_state.line_sum, gdbserver_state.line_csum); 2293 /* send NAK reply */ 2294 reply = '-'; 2295 gdb_put_buffer(&reply, 1); 2296 gdbserver_state.state = RS_IDLE; 2297 } else { 2298 /* send ACK reply */ 2299 reply = '+'; 2300 gdb_put_buffer(&reply, 1); 2301 gdbserver_state.state = gdb_handle_packet(gdbserver_state.line_buf); 2302 } 2303 break; 2304 default: 2305 abort(); 2306 } 2307 } 2308 } 2309 2310 /* 2311 * Create the process that will contain all the "orphan" CPUs (that are not 2312 * part of a CPU cluster). Note that if this process contains no CPUs, it won't 2313 * be attachable and thus will be invisible to the user. 2314 */ 2315 void gdb_create_default_process(GDBState *s) 2316 { 2317 GDBProcess *process; 2318 int pid; 2319 2320 #ifdef CONFIG_USER_ONLY 2321 assert(gdbserver_state.process_num == 0); 2322 pid = getpid(); 2323 #else 2324 if (gdbserver_state.process_num) { 2325 pid = s->processes[s->process_num - 1].pid; 2326 } else { 2327 pid = 0; 2328 } 2329 /* We need an available PID slot for this process */ 2330 assert(pid < UINT32_MAX); 2331 pid++; 2332 #endif 2333 2334 s->processes = g_renew(GDBProcess, s->processes, ++s->process_num); 2335 process = &s->processes[s->process_num - 1]; 2336 process->pid = pid; 2337 process->attached = false; 2338 process->target_xml = NULL; 2339 } 2340 2341