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 gdb_get_reg_cb get_reg; 51 gdb_set_reg_cb set_reg; 52 const GDBFeature *feature; 53 } GDBRegisterState; 54 55 GDBState gdbserver_state; 56 57 void gdb_init_gdbserver_state(void) 58 { 59 g_assert(!gdbserver_state.init); 60 memset(&gdbserver_state, 0, sizeof(GDBState)); 61 gdbserver_state.init = true; 62 gdbserver_state.str_buf = g_string_new(NULL); 63 gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH); 64 gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4); 65 66 /* 67 * What single-step modes are supported is accelerator dependent. 68 * By default try to use no IRQs and no timers while single 69 * stepping so as to make single stepping like a typical ICE HW step. 70 */ 71 gdbserver_state.supported_sstep_flags = accel_supported_gdbstub_sstep_flags(); 72 gdbserver_state.sstep_flags = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER; 73 gdbserver_state.sstep_flags &= gdbserver_state.supported_sstep_flags; 74 } 75 76 /* writes 2*len+1 bytes in buf */ 77 void gdb_memtohex(GString *buf, const uint8_t *mem, int len) 78 { 79 int i, c; 80 for(i = 0; i < len; i++) { 81 c = mem[i]; 82 g_string_append_c(buf, tohex(c >> 4)); 83 g_string_append_c(buf, tohex(c & 0xf)); 84 } 85 g_string_append_c(buf, '\0'); 86 } 87 88 void gdb_hextomem(GByteArray *mem, const char *buf, int len) 89 { 90 int i; 91 92 for(i = 0; i < len; i++) { 93 guint8 byte = fromhex(buf[0]) << 4 | fromhex(buf[1]); 94 g_byte_array_append(mem, &byte, 1); 95 buf += 2; 96 } 97 } 98 99 static void hexdump(const char *buf, int len, 100 void (*trace_fn)(size_t ofs, char const *text)) 101 { 102 char line_buffer[3 * 16 + 4 + 16 + 1]; 103 104 size_t i; 105 for (i = 0; i < len || (i & 0xF); ++i) { 106 size_t byte_ofs = i & 15; 107 108 if (byte_ofs == 0) { 109 memset(line_buffer, ' ', 3 * 16 + 4 + 16); 110 line_buffer[3 * 16 + 4 + 16] = 0; 111 } 112 113 size_t col_group = (i >> 2) & 3; 114 size_t hex_col = byte_ofs * 3 + col_group; 115 size_t txt_col = 3 * 16 + 4 + byte_ofs; 116 117 if (i < len) { 118 char value = buf[i]; 119 120 line_buffer[hex_col + 0] = tohex((value >> 4) & 0xF); 121 line_buffer[hex_col + 1] = tohex((value >> 0) & 0xF); 122 line_buffer[txt_col + 0] = (value >= ' ' && value < 127) 123 ? value 124 : '.'; 125 } 126 127 if (byte_ofs == 0xF) 128 trace_fn(i & -16, line_buffer); 129 } 130 } 131 132 /* return -1 if error, 0 if OK */ 133 int gdb_put_packet_binary(const char *buf, int len, bool dump) 134 { 135 int csum, i; 136 uint8_t footer[3]; 137 138 if (dump && trace_event_get_state_backends(TRACE_GDBSTUB_IO_BINARYREPLY)) { 139 hexdump(buf, len, trace_gdbstub_io_binaryreply); 140 } 141 142 for(;;) { 143 g_byte_array_set_size(gdbserver_state.last_packet, 0); 144 g_byte_array_append(gdbserver_state.last_packet, 145 (const uint8_t *) "$", 1); 146 g_byte_array_append(gdbserver_state.last_packet, 147 (const uint8_t *) buf, len); 148 csum = 0; 149 for(i = 0; i < len; i++) { 150 csum += buf[i]; 151 } 152 footer[0] = '#'; 153 footer[1] = tohex((csum >> 4) & 0xf); 154 footer[2] = tohex((csum) & 0xf); 155 g_byte_array_append(gdbserver_state.last_packet, footer, 3); 156 157 gdb_put_buffer(gdbserver_state.last_packet->data, 158 gdbserver_state.last_packet->len); 159 160 if (gdb_got_immediate_ack()) { 161 break; 162 } 163 } 164 return 0; 165 } 166 167 /* return -1 if error, 0 if OK */ 168 int gdb_put_packet(const char *buf) 169 { 170 trace_gdbstub_io_reply(buf); 171 172 return gdb_put_packet_binary(buf, strlen(buf), false); 173 } 174 175 void gdb_put_strbuf(void) 176 { 177 gdb_put_packet(gdbserver_state.str_buf->str); 178 } 179 180 /* Encode data using the encoding for 'x' packets. */ 181 void gdb_memtox(GString *buf, const char *mem, int len) 182 { 183 char c; 184 185 while (len--) { 186 c = *(mem++); 187 switch (c) { 188 case '#': case '$': case '*': case '}': 189 g_string_append_c(buf, '}'); 190 g_string_append_c(buf, c ^ 0x20); 191 break; 192 default: 193 g_string_append_c(buf, c); 194 break; 195 } 196 } 197 } 198 199 static uint32_t gdb_get_cpu_pid(CPUState *cpu) 200 { 201 #ifdef CONFIG_USER_ONLY 202 return getpid(); 203 #else 204 if (cpu->cluster_index == UNASSIGNED_CLUSTER_INDEX) { 205 /* Return the default process' PID */ 206 int index = gdbserver_state.process_num - 1; 207 return gdbserver_state.processes[index].pid; 208 } 209 return cpu->cluster_index + 1; 210 #endif 211 } 212 213 GDBProcess *gdb_get_process(uint32_t pid) 214 { 215 int i; 216 217 if (!pid) { 218 /* 0 means any process, we take the first one */ 219 return &gdbserver_state.processes[0]; 220 } 221 222 for (i = 0; i < gdbserver_state.process_num; i++) { 223 if (gdbserver_state.processes[i].pid == pid) { 224 return &gdbserver_state.processes[i]; 225 } 226 } 227 228 return NULL; 229 } 230 231 static GDBProcess *gdb_get_cpu_process(CPUState *cpu) 232 { 233 return gdb_get_process(gdb_get_cpu_pid(cpu)); 234 } 235 236 static CPUState *find_cpu(uint32_t thread_id) 237 { 238 CPUState *cpu; 239 240 CPU_FOREACH(cpu) { 241 if (gdb_get_cpu_index(cpu) == thread_id) { 242 return cpu; 243 } 244 } 245 246 return NULL; 247 } 248 249 CPUState *gdb_get_first_cpu_in_process(GDBProcess *process) 250 { 251 CPUState *cpu; 252 253 CPU_FOREACH(cpu) { 254 if (gdb_get_cpu_pid(cpu) == process->pid) { 255 return cpu; 256 } 257 } 258 259 return NULL; 260 } 261 262 static CPUState *gdb_next_cpu_in_process(CPUState *cpu) 263 { 264 uint32_t pid = gdb_get_cpu_pid(cpu); 265 cpu = CPU_NEXT(cpu); 266 267 while (cpu) { 268 if (gdb_get_cpu_pid(cpu) == pid) { 269 break; 270 } 271 272 cpu = CPU_NEXT(cpu); 273 } 274 275 return cpu; 276 } 277 278 /* Return the cpu following @cpu, while ignoring unattached processes. */ 279 static CPUState *gdb_next_attached_cpu(CPUState *cpu) 280 { 281 cpu = CPU_NEXT(cpu); 282 283 while (cpu) { 284 if (gdb_get_cpu_process(cpu)->attached) { 285 break; 286 } 287 288 cpu = CPU_NEXT(cpu); 289 } 290 291 return cpu; 292 } 293 294 /* Return the first attached cpu */ 295 CPUState *gdb_first_attached_cpu(void) 296 { 297 CPUState *cpu = first_cpu; 298 GDBProcess *process = gdb_get_cpu_process(cpu); 299 300 if (!process->attached) { 301 return gdb_next_attached_cpu(cpu); 302 } 303 304 return cpu; 305 } 306 307 static CPUState *gdb_get_cpu(uint32_t pid, uint32_t tid) 308 { 309 GDBProcess *process; 310 CPUState *cpu; 311 312 if (!pid && !tid) { 313 /* 0 means any process/thread, we take the first attached one */ 314 return gdb_first_attached_cpu(); 315 } else if (pid && !tid) { 316 /* any thread in a specific process */ 317 process = gdb_get_process(pid); 318 319 if (process == NULL) { 320 return NULL; 321 } 322 323 if (!process->attached) { 324 return NULL; 325 } 326 327 return gdb_get_first_cpu_in_process(process); 328 } else { 329 /* a specific thread */ 330 cpu = find_cpu(tid); 331 332 if (cpu == NULL) { 333 return NULL; 334 } 335 336 process = gdb_get_cpu_process(cpu); 337 338 if (pid && process->pid != pid) { 339 return NULL; 340 } 341 342 if (!process->attached) { 343 return NULL; 344 } 345 346 return cpu; 347 } 348 } 349 350 static const char *get_feature_xml(const char *p, const char **newp, 351 GDBProcess *process) 352 { 353 CPUState *cpu = gdb_get_first_cpu_in_process(process); 354 CPUClass *cc = CPU_GET_CLASS(cpu); 355 GDBRegisterState *r; 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 g_autoptr(GPtrArray) xml = g_ptr_array_new_with_free_func(g_free); 370 371 g_ptr_array_add( 372 xml, 373 g_strdup("<?xml version=\"1.0\"?>" 374 "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">" 375 "<target>")); 376 377 if (cc->gdb_arch_name) { 378 g_ptr_array_add( 379 xml, 380 g_markup_printf_escaped("<architecture>%s</architecture>", 381 cc->gdb_arch_name(cpu))); 382 } 383 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 384 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 385 g_ptr_array_add( 386 xml, 387 g_markup_printf_escaped("<xi:include href=\"%s\"/>", 388 r->feature->xmlname)); 389 } 390 g_ptr_array_add(xml, g_strdup("</target>")); 391 g_ptr_array_add(xml, NULL); 392 393 process->target_xml = g_strjoinv(NULL, (void *)xml->pdata); 394 } 395 return process->target_xml; 396 } 397 /* Is it one of the features? */ 398 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 399 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 400 if (strncmp(p, r->feature->xmlname, len) == 0) { 401 return r->feature->xml; 402 } 403 } 404 405 /* failed */ 406 return NULL; 407 } 408 409 void gdb_feature_builder_init(GDBFeatureBuilder *builder, GDBFeature *feature, 410 const char *name, const char *xmlname, 411 int base_reg) 412 { 413 char *header = g_markup_printf_escaped( 414 "<?xml version=\"1.0\"?>" 415 "<!DOCTYPE feature SYSTEM \"gdb-target.dtd\">" 416 "<feature name=\"%s\">", 417 name); 418 419 builder->feature = feature; 420 builder->xml = g_ptr_array_new(); 421 g_ptr_array_add(builder->xml, header); 422 builder->base_reg = base_reg; 423 feature->xmlname = xmlname; 424 feature->num_regs = 0; 425 } 426 427 void gdb_feature_builder_append_tag(const GDBFeatureBuilder *builder, 428 const char *format, ...) 429 { 430 va_list ap; 431 va_start(ap, format); 432 g_ptr_array_add(builder->xml, g_markup_vprintf_escaped(format, ap)); 433 va_end(ap); 434 } 435 436 void gdb_feature_builder_append_reg(const GDBFeatureBuilder *builder, 437 const char *name, 438 int bitsize, 439 int regnum, 440 const char *type, 441 const char *group) 442 { 443 if (builder->feature->num_regs < regnum) { 444 builder->feature->num_regs = regnum; 445 } 446 447 if (group) { 448 gdb_feature_builder_append_tag( 449 builder, 450 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\" group=\"%s\"/>", 451 name, bitsize, builder->base_reg + regnum, type, group); 452 } else { 453 gdb_feature_builder_append_tag( 454 builder, 455 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\"/>", 456 name, bitsize, builder->base_reg + regnum, type); 457 } 458 } 459 460 void gdb_feature_builder_end(const GDBFeatureBuilder *builder) 461 { 462 g_ptr_array_add(builder->xml, (void *)"</feature>"); 463 g_ptr_array_add(builder->xml, NULL); 464 465 builder->feature->xml = g_strjoinv(NULL, (void *)builder->xml->pdata); 466 467 for (guint i = 0; i < builder->xml->len - 2; i++) { 468 g_free(g_ptr_array_index(builder->xml, i)); 469 } 470 471 g_ptr_array_free(builder->xml, TRUE); 472 } 473 474 const GDBFeature *gdb_find_static_feature(const char *xmlname) 475 { 476 const GDBFeature *feature; 477 478 for (feature = gdb_static_features; feature->xmlname; feature++) { 479 if (!strcmp(feature->xmlname, xmlname)) { 480 return feature; 481 } 482 } 483 484 g_assert_not_reached(); 485 } 486 487 static int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg) 488 { 489 CPUClass *cc = CPU_GET_CLASS(cpu); 490 GDBRegisterState *r; 491 492 if (reg < cc->gdb_num_core_regs) { 493 return cc->gdb_read_register(cpu, buf, reg); 494 } 495 496 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 497 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 498 if (r->base_reg <= reg && reg < r->base_reg + r->feature->num_regs) { 499 return r->get_reg(cpu, buf, reg - r->base_reg); 500 } 501 } 502 return 0; 503 } 504 505 static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg) 506 { 507 CPUClass *cc = CPU_GET_CLASS(cpu); 508 GDBRegisterState *r; 509 510 if (reg < cc->gdb_num_core_regs) { 511 return cc->gdb_write_register(cpu, mem_buf, reg); 512 } 513 514 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->feature->num_regs) { 517 return r->set_reg(cpu, mem_buf, reg - r->base_reg); 518 } 519 } 520 return 0; 521 } 522 523 static void gdb_register_feature(CPUState *cpu, int base_reg, 524 gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg, 525 const GDBFeature *feature) 526 { 527 GDBRegisterState s = { 528 .base_reg = base_reg, 529 .get_reg = get_reg, 530 .set_reg = set_reg, 531 .feature = feature 532 }; 533 534 g_array_append_val(cpu->gdb_regs, s); 535 } 536 537 void gdb_init_cpu(CPUState *cpu) 538 { 539 CPUClass *cc = CPU_GET_CLASS(cpu); 540 const GDBFeature *feature; 541 542 cpu->gdb_regs = g_array_new(false, false, sizeof(GDBRegisterState)); 543 544 if (cc->gdb_core_xml_file) { 545 feature = gdb_find_static_feature(cc->gdb_core_xml_file); 546 gdb_register_feature(cpu, 0, 547 cc->gdb_read_register, cc->gdb_write_register, 548 feature); 549 } 550 551 cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs; 552 } 553 554 void gdb_register_coprocessor(CPUState *cpu, 555 gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg, 556 const GDBFeature *feature, int g_pos) 557 { 558 GDBRegisterState *s; 559 guint i; 560 int base_reg = cpu->gdb_num_regs; 561 562 for (i = 0; i < cpu->gdb_regs->len; i++) { 563 /* Check for duplicates. */ 564 s = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 565 if (s->feature == feature) { 566 return; 567 } 568 } 569 570 gdb_register_feature(cpu, base_reg, get_reg, set_reg, feature); 571 572 /* Add to end of list. */ 573 cpu->gdb_num_regs += feature->num_regs; 574 if (g_pos) { 575 if (g_pos != base_reg) { 576 error_report("Error: Bad gdb register numbering for '%s', " 577 "expected %d got %d", feature->xml, g_pos, base_reg); 578 } else { 579 cpu->gdb_num_g_regs = cpu->gdb_num_regs; 580 } 581 } 582 } 583 584 static void gdb_process_breakpoint_remove_all(GDBProcess *p) 585 { 586 CPUState *cpu = gdb_get_first_cpu_in_process(p); 587 588 while (cpu) { 589 gdb_breakpoint_remove_all(cpu); 590 cpu = gdb_next_cpu_in_process(cpu); 591 } 592 } 593 594 595 static void gdb_set_cpu_pc(vaddr pc) 596 { 597 CPUState *cpu = gdbserver_state.c_cpu; 598 599 cpu_synchronize_state(cpu); 600 cpu_set_pc(cpu, pc); 601 } 602 603 void gdb_append_thread_id(CPUState *cpu, GString *buf) 604 { 605 if (gdbserver_state.multiprocess) { 606 g_string_append_printf(buf, "p%02x.%02x", 607 gdb_get_cpu_pid(cpu), gdb_get_cpu_index(cpu)); 608 } else { 609 g_string_append_printf(buf, "%02x", gdb_get_cpu_index(cpu)); 610 } 611 } 612 613 static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf, 614 uint32_t *pid, uint32_t *tid) 615 { 616 unsigned long p, t; 617 int ret; 618 619 if (*buf == 'p') { 620 buf++; 621 ret = qemu_strtoul(buf, &buf, 16, &p); 622 623 if (ret) { 624 return GDB_READ_THREAD_ERR; 625 } 626 627 /* Skip '.' */ 628 buf++; 629 } else { 630 p = 0; 631 } 632 633 ret = qemu_strtoul(buf, &buf, 16, &t); 634 635 if (ret) { 636 return GDB_READ_THREAD_ERR; 637 } 638 639 *end_buf = buf; 640 641 if (p == -1) { 642 return GDB_ALL_PROCESSES; 643 } 644 645 if (pid) { 646 *pid = p; 647 } 648 649 if (t == -1) { 650 return GDB_ALL_THREADS; 651 } 652 653 if (tid) { 654 *tid = t; 655 } 656 657 return GDB_ONE_THREAD; 658 } 659 660 /** 661 * gdb_handle_vcont - Parses and handles a vCont packet. 662 * returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is 663 * a format error, 0 on success. 664 */ 665 static int gdb_handle_vcont(const char *p) 666 { 667 int res, signal = 0; 668 char cur_action; 669 unsigned long tmp; 670 uint32_t pid, tid; 671 GDBProcess *process; 672 CPUState *cpu; 673 GDBThreadIdKind kind; 674 unsigned int max_cpus = gdb_get_max_cpus(); 675 /* uninitialised CPUs stay 0 */ 676 g_autofree char *newstates = g_new0(char, max_cpus); 677 678 /* mark valid CPUs with 1 */ 679 CPU_FOREACH(cpu) { 680 newstates[cpu->cpu_index] = 1; 681 } 682 683 /* 684 * res keeps track of what error we are returning, with -ENOTSUP meaning 685 * that the command is unknown or unsupported, thus returning an empty 686 * packet, while -EINVAL and -ERANGE cause an E22 packet, due to invalid, 687 * or incorrect parameters passed. 688 */ 689 res = 0; 690 691 /* 692 * target_count and last_target keep track of how many CPUs we are going to 693 * step or resume, and a pointer to the state structure of one of them, 694 * respectively 695 */ 696 int target_count = 0; 697 CPUState *last_target = NULL; 698 699 while (*p) { 700 if (*p++ != ';') { 701 return -ENOTSUP; 702 } 703 704 cur_action = *p++; 705 if (cur_action == 'C' || cur_action == 'S') { 706 cur_action = qemu_tolower(cur_action); 707 res = qemu_strtoul(p, &p, 16, &tmp); 708 if (res) { 709 return res; 710 } 711 signal = gdb_signal_to_target(tmp); 712 } else if (cur_action != 'c' && cur_action != 's') { 713 /* unknown/invalid/unsupported command */ 714 return -ENOTSUP; 715 } 716 717 if (*p == '\0' || *p == ';') { 718 /* 719 * No thread specifier, action is on "all threads". The 720 * specification is unclear regarding the process to act on. We 721 * choose all processes. 722 */ 723 kind = GDB_ALL_PROCESSES; 724 } else if (*p++ == ':') { 725 kind = read_thread_id(p, &p, &pid, &tid); 726 } else { 727 return -ENOTSUP; 728 } 729 730 switch (kind) { 731 case GDB_READ_THREAD_ERR: 732 return -EINVAL; 733 734 case GDB_ALL_PROCESSES: 735 cpu = gdb_first_attached_cpu(); 736 while (cpu) { 737 if (newstates[cpu->cpu_index] == 1) { 738 newstates[cpu->cpu_index] = cur_action; 739 740 target_count++; 741 last_target = cpu; 742 } 743 744 cpu = gdb_next_attached_cpu(cpu); 745 } 746 break; 747 748 case GDB_ALL_THREADS: 749 process = gdb_get_process(pid); 750 751 if (!process->attached) { 752 return -EINVAL; 753 } 754 755 cpu = gdb_get_first_cpu_in_process(process); 756 while (cpu) { 757 if (newstates[cpu->cpu_index] == 1) { 758 newstates[cpu->cpu_index] = cur_action; 759 760 target_count++; 761 last_target = cpu; 762 } 763 764 cpu = gdb_next_cpu_in_process(cpu); 765 } 766 break; 767 768 case GDB_ONE_THREAD: 769 cpu = gdb_get_cpu(pid, tid); 770 771 /* invalid CPU/thread specified */ 772 if (!cpu) { 773 return -EINVAL; 774 } 775 776 /* only use if no previous match occourred */ 777 if (newstates[cpu->cpu_index] == 1) { 778 newstates[cpu->cpu_index] = cur_action; 779 780 target_count++; 781 last_target = cpu; 782 } 783 break; 784 } 785 } 786 787 /* 788 * if we're about to resume a specific set of CPUs/threads, make it so that 789 * in case execution gets interrupted, we can send GDB a stop reply with a 790 * correct value. it doesn't really matter which CPU we tell GDB the signal 791 * happened in (VM pauses stop all of them anyway), so long as it is one of 792 * the ones we resumed/single stepped here. 793 */ 794 if (target_count > 0) { 795 gdbserver_state.c_cpu = last_target; 796 } 797 798 gdbserver_state.signal = signal; 799 gdb_continue_partial(newstates); 800 return res; 801 } 802 803 static const char *cmd_next_param(const char *param, const char delimiter) 804 { 805 static const char all_delimiters[] = ",;:="; 806 char curr_delimiters[2] = {0}; 807 const char *delimiters; 808 809 if (delimiter == '?') { 810 delimiters = all_delimiters; 811 } else if (delimiter == '0') { 812 return strchr(param, '\0'); 813 } else if (delimiter == '.' && *param) { 814 return param + 1; 815 } else { 816 curr_delimiters[0] = delimiter; 817 delimiters = curr_delimiters; 818 } 819 820 param += strcspn(param, delimiters); 821 if (*param) { 822 param++; 823 } 824 return param; 825 } 826 827 static int cmd_parse_params(const char *data, const char *schema, 828 GArray *params) 829 { 830 const char *curr_schema, *curr_data; 831 832 g_assert(schema); 833 g_assert(params->len == 0); 834 835 curr_schema = schema; 836 curr_data = data; 837 while (curr_schema[0] && curr_schema[1] && *curr_data) { 838 GdbCmdVariant this_param; 839 840 switch (curr_schema[0]) { 841 case 'l': 842 if (qemu_strtoul(curr_data, &curr_data, 16, 843 &this_param.val_ul)) { 844 return -EINVAL; 845 } 846 curr_data = cmd_next_param(curr_data, curr_schema[1]); 847 g_array_append_val(params, this_param); 848 break; 849 case 'L': 850 if (qemu_strtou64(curr_data, &curr_data, 16, 851 (uint64_t *)&this_param.val_ull)) { 852 return -EINVAL; 853 } 854 curr_data = cmd_next_param(curr_data, curr_schema[1]); 855 g_array_append_val(params, this_param); 856 break; 857 case 's': 858 this_param.data = curr_data; 859 curr_data = cmd_next_param(curr_data, curr_schema[1]); 860 g_array_append_val(params, this_param); 861 break; 862 case 'o': 863 this_param.opcode = *(uint8_t *)curr_data; 864 curr_data = cmd_next_param(curr_data, curr_schema[1]); 865 g_array_append_val(params, this_param); 866 break; 867 case 't': 868 this_param.thread_id.kind = 869 read_thread_id(curr_data, &curr_data, 870 &this_param.thread_id.pid, 871 &this_param.thread_id.tid); 872 curr_data = cmd_next_param(curr_data, curr_schema[1]); 873 g_array_append_val(params, this_param); 874 break; 875 case '?': 876 curr_data = cmd_next_param(curr_data, curr_schema[1]); 877 break; 878 default: 879 return -EINVAL; 880 } 881 curr_schema += 2; 882 } 883 884 return 0; 885 } 886 887 typedef void (*GdbCmdHandler)(GArray *params, void *user_ctx); 888 889 /* 890 * cmd_startswith -> cmd is compared using startswith 891 * 892 * allow_stop_reply -> true iff the gdbstub can respond to this command with a 893 * "stop reply" packet. The list of commands that accept such response is 894 * defined at the GDB Remote Serial Protocol documentation. see: 895 * https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets. 896 * 897 * schema definitions: 898 * Each schema parameter entry consists of 2 chars, 899 * the first char represents the parameter type handling 900 * the second char represents the delimiter for the next parameter 901 * 902 * Currently supported schema types: 903 * 'l' -> unsigned long (stored in .val_ul) 904 * 'L' -> unsigned long long (stored in .val_ull) 905 * 's' -> string (stored in .data) 906 * 'o' -> single char (stored in .opcode) 907 * 't' -> thread id (stored in .thread_id) 908 * '?' -> skip according to delimiter 909 * 910 * Currently supported delimiters: 911 * '?' -> Stop at any delimiter (",;:=\0") 912 * '0' -> Stop at "\0" 913 * '.' -> Skip 1 char unless reached "\0" 914 * Any other value is treated as the delimiter value itself 915 */ 916 typedef struct GdbCmdParseEntry { 917 GdbCmdHandler handler; 918 const char *cmd; 919 bool cmd_startswith; 920 const char *schema; 921 bool allow_stop_reply; 922 } GdbCmdParseEntry; 923 924 static inline int startswith(const char *string, const char *pattern) 925 { 926 return !strncmp(string, pattern, strlen(pattern)); 927 } 928 929 static int process_string_cmd(const char *data, 930 const GdbCmdParseEntry *cmds, int num_cmds) 931 { 932 int i; 933 g_autoptr(GArray) params = g_array_new(false, true, sizeof(GdbCmdVariant)); 934 935 if (!cmds) { 936 return -1; 937 } 938 939 for (i = 0; i < num_cmds; i++) { 940 const GdbCmdParseEntry *cmd = &cmds[i]; 941 g_assert(cmd->handler && cmd->cmd); 942 943 if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) || 944 (!cmd->cmd_startswith && strcmp(cmd->cmd, data))) { 945 continue; 946 } 947 948 if (cmd->schema) { 949 if (cmd_parse_params(&data[strlen(cmd->cmd)], 950 cmd->schema, params)) { 951 return -1; 952 } 953 } 954 955 gdbserver_state.allow_stop_reply = cmd->allow_stop_reply; 956 cmd->handler(params, NULL); 957 return 0; 958 } 959 960 return -1; 961 } 962 963 static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd) 964 { 965 if (!data) { 966 return; 967 } 968 969 g_string_set_size(gdbserver_state.str_buf, 0); 970 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 971 972 /* In case there was an error during the command parsing we must 973 * send a NULL packet to indicate the command is not supported */ 974 if (process_string_cmd(data, cmd, 1)) { 975 gdb_put_packet(""); 976 } 977 } 978 979 static void handle_detach(GArray *params, void *user_ctx) 980 { 981 GDBProcess *process; 982 uint32_t pid = 1; 983 984 if (gdbserver_state.multiprocess) { 985 if (!params->len) { 986 gdb_put_packet("E22"); 987 return; 988 } 989 990 pid = get_param(params, 0)->val_ul; 991 } 992 993 process = gdb_get_process(pid); 994 gdb_process_breakpoint_remove_all(process); 995 process->attached = false; 996 997 if (pid == gdb_get_cpu_pid(gdbserver_state.c_cpu)) { 998 gdbserver_state.c_cpu = gdb_first_attached_cpu(); 999 } 1000 1001 if (pid == gdb_get_cpu_pid(gdbserver_state.g_cpu)) { 1002 gdbserver_state.g_cpu = gdb_first_attached_cpu(); 1003 } 1004 1005 if (!gdbserver_state.c_cpu) { 1006 /* No more process attached */ 1007 gdb_disable_syscalls(); 1008 gdb_continue(); 1009 } 1010 gdb_put_packet("OK"); 1011 } 1012 1013 static void handle_thread_alive(GArray *params, void *user_ctx) 1014 { 1015 CPUState *cpu; 1016 1017 if (!params->len) { 1018 gdb_put_packet("E22"); 1019 return; 1020 } 1021 1022 if (get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1023 gdb_put_packet("E22"); 1024 return; 1025 } 1026 1027 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1028 get_param(params, 0)->thread_id.tid); 1029 if (!cpu) { 1030 gdb_put_packet("E22"); 1031 return; 1032 } 1033 1034 gdb_put_packet("OK"); 1035 } 1036 1037 static void handle_continue(GArray *params, void *user_ctx) 1038 { 1039 if (params->len) { 1040 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1041 } 1042 1043 gdbserver_state.signal = 0; 1044 gdb_continue(); 1045 } 1046 1047 static void handle_cont_with_sig(GArray *params, void *user_ctx) 1048 { 1049 unsigned long signal = 0; 1050 1051 /* 1052 * Note: C sig;[addr] is currently unsupported and we simply 1053 * omit the addr parameter 1054 */ 1055 if (params->len) { 1056 signal = get_param(params, 0)->val_ul; 1057 } 1058 1059 gdbserver_state.signal = gdb_signal_to_target(signal); 1060 if (gdbserver_state.signal == -1) { 1061 gdbserver_state.signal = 0; 1062 } 1063 gdb_continue(); 1064 } 1065 1066 static void handle_set_thread(GArray *params, void *user_ctx) 1067 { 1068 CPUState *cpu; 1069 1070 if (params->len != 2) { 1071 gdb_put_packet("E22"); 1072 return; 1073 } 1074 1075 if (get_param(params, 1)->thread_id.kind == GDB_READ_THREAD_ERR) { 1076 gdb_put_packet("E22"); 1077 return; 1078 } 1079 1080 if (get_param(params, 1)->thread_id.kind != GDB_ONE_THREAD) { 1081 gdb_put_packet("OK"); 1082 return; 1083 } 1084 1085 cpu = gdb_get_cpu(get_param(params, 1)->thread_id.pid, 1086 get_param(params, 1)->thread_id.tid); 1087 if (!cpu) { 1088 gdb_put_packet("E22"); 1089 return; 1090 } 1091 1092 /* 1093 * Note: This command is deprecated and modern gdb's will be using the 1094 * vCont command instead. 1095 */ 1096 switch (get_param(params, 0)->opcode) { 1097 case 'c': 1098 gdbserver_state.c_cpu = cpu; 1099 gdb_put_packet("OK"); 1100 break; 1101 case 'g': 1102 gdbserver_state.g_cpu = cpu; 1103 gdb_put_packet("OK"); 1104 break; 1105 default: 1106 gdb_put_packet("E22"); 1107 break; 1108 } 1109 } 1110 1111 static void handle_insert_bp(GArray *params, void *user_ctx) 1112 { 1113 int res; 1114 1115 if (params->len != 3) { 1116 gdb_put_packet("E22"); 1117 return; 1118 } 1119 1120 res = gdb_breakpoint_insert(gdbserver_state.c_cpu, 1121 get_param(params, 0)->val_ul, 1122 get_param(params, 1)->val_ull, 1123 get_param(params, 2)->val_ull); 1124 if (res >= 0) { 1125 gdb_put_packet("OK"); 1126 return; 1127 } else if (res == -ENOSYS) { 1128 gdb_put_packet(""); 1129 return; 1130 } 1131 1132 gdb_put_packet("E22"); 1133 } 1134 1135 static void handle_remove_bp(GArray *params, void *user_ctx) 1136 { 1137 int res; 1138 1139 if (params->len != 3) { 1140 gdb_put_packet("E22"); 1141 return; 1142 } 1143 1144 res = gdb_breakpoint_remove(gdbserver_state.c_cpu, 1145 get_param(params, 0)->val_ul, 1146 get_param(params, 1)->val_ull, 1147 get_param(params, 2)->val_ull); 1148 if (res >= 0) { 1149 gdb_put_packet("OK"); 1150 return; 1151 } else if (res == -ENOSYS) { 1152 gdb_put_packet(""); 1153 return; 1154 } 1155 1156 gdb_put_packet("E22"); 1157 } 1158 1159 /* 1160 * handle_set/get_reg 1161 * 1162 * Older gdb are really dumb, and don't use 'G/g' if 'P/p' is available. 1163 * This works, but can be very slow. Anything new enough to understand 1164 * XML also knows how to use this properly. However to use this we 1165 * need to define a local XML file as well as be talking to a 1166 * reasonably modern gdb. Responding with an empty packet will cause 1167 * the remote gdb to fallback to older methods. 1168 */ 1169 1170 static void handle_set_reg(GArray *params, void *user_ctx) 1171 { 1172 int reg_size; 1173 1174 if (params->len != 2) { 1175 gdb_put_packet("E22"); 1176 return; 1177 } 1178 1179 reg_size = strlen(get_param(params, 1)->data) / 2; 1180 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, reg_size); 1181 gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data, 1182 get_param(params, 0)->val_ull); 1183 gdb_put_packet("OK"); 1184 } 1185 1186 static void handle_get_reg(GArray *params, void *user_ctx) 1187 { 1188 int reg_size; 1189 1190 if (!params->len) { 1191 gdb_put_packet("E14"); 1192 return; 1193 } 1194 1195 reg_size = gdb_read_register(gdbserver_state.g_cpu, 1196 gdbserver_state.mem_buf, 1197 get_param(params, 0)->val_ull); 1198 if (!reg_size) { 1199 gdb_put_packet("E14"); 1200 return; 1201 } else { 1202 g_byte_array_set_size(gdbserver_state.mem_buf, reg_size); 1203 } 1204 1205 gdb_memtohex(gdbserver_state.str_buf, 1206 gdbserver_state.mem_buf->data, reg_size); 1207 gdb_put_strbuf(); 1208 } 1209 1210 static void handle_write_mem(GArray *params, void *user_ctx) 1211 { 1212 if (params->len != 3) { 1213 gdb_put_packet("E22"); 1214 return; 1215 } 1216 1217 /* gdb_hextomem() reads 2*len bytes */ 1218 if (get_param(params, 1)->val_ull > 1219 strlen(get_param(params, 2)->data) / 2) { 1220 gdb_put_packet("E22"); 1221 return; 1222 } 1223 1224 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 2)->data, 1225 get_param(params, 1)->val_ull); 1226 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1227 get_param(params, 0)->val_ull, 1228 gdbserver_state.mem_buf->data, 1229 gdbserver_state.mem_buf->len, true)) { 1230 gdb_put_packet("E14"); 1231 return; 1232 } 1233 1234 gdb_put_packet("OK"); 1235 } 1236 1237 static void handle_read_mem(GArray *params, void *user_ctx) 1238 { 1239 if (params->len != 2) { 1240 gdb_put_packet("E22"); 1241 return; 1242 } 1243 1244 /* gdb_memtohex() doubles the required space */ 1245 if (get_param(params, 1)->val_ull > MAX_PACKET_LENGTH / 2) { 1246 gdb_put_packet("E22"); 1247 return; 1248 } 1249 1250 g_byte_array_set_size(gdbserver_state.mem_buf, 1251 get_param(params, 1)->val_ull); 1252 1253 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1254 get_param(params, 0)->val_ull, 1255 gdbserver_state.mem_buf->data, 1256 gdbserver_state.mem_buf->len, false)) { 1257 gdb_put_packet("E14"); 1258 return; 1259 } 1260 1261 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, 1262 gdbserver_state.mem_buf->len); 1263 gdb_put_strbuf(); 1264 } 1265 1266 static void handle_write_all_regs(GArray *params, void *user_ctx) 1267 { 1268 int reg_id; 1269 size_t len; 1270 uint8_t *registers; 1271 int reg_size; 1272 1273 if (!params->len) { 1274 return; 1275 } 1276 1277 cpu_synchronize_state(gdbserver_state.g_cpu); 1278 len = strlen(get_param(params, 0)->data) / 2; 1279 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 0)->data, len); 1280 registers = gdbserver_state.mem_buf->data; 1281 for (reg_id = 0; 1282 reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0; 1283 reg_id++) { 1284 reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id); 1285 len -= reg_size; 1286 registers += reg_size; 1287 } 1288 gdb_put_packet("OK"); 1289 } 1290 1291 static void handle_read_all_regs(GArray *params, void *user_ctx) 1292 { 1293 int reg_id; 1294 size_t len; 1295 1296 cpu_synchronize_state(gdbserver_state.g_cpu); 1297 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 1298 len = 0; 1299 for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) { 1300 len += gdb_read_register(gdbserver_state.g_cpu, 1301 gdbserver_state.mem_buf, 1302 reg_id); 1303 } 1304 g_assert(len == gdbserver_state.mem_buf->len); 1305 1306 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len); 1307 gdb_put_strbuf(); 1308 } 1309 1310 1311 static void handle_step(GArray *params, void *user_ctx) 1312 { 1313 if (params->len) { 1314 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1315 } 1316 1317 cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags); 1318 gdb_continue(); 1319 } 1320 1321 static void handle_backward(GArray *params, void *user_ctx) 1322 { 1323 if (!gdb_can_reverse()) { 1324 gdb_put_packet("E22"); 1325 } 1326 if (params->len == 1) { 1327 switch (get_param(params, 0)->opcode) { 1328 case 's': 1329 if (replay_reverse_step()) { 1330 gdb_continue(); 1331 } else { 1332 gdb_put_packet("E14"); 1333 } 1334 return; 1335 case 'c': 1336 if (replay_reverse_continue()) { 1337 gdb_continue(); 1338 } else { 1339 gdb_put_packet("E14"); 1340 } 1341 return; 1342 } 1343 } 1344 1345 /* Default invalid command */ 1346 gdb_put_packet(""); 1347 } 1348 1349 static void handle_v_cont_query(GArray *params, void *user_ctx) 1350 { 1351 gdb_put_packet("vCont;c;C;s;S"); 1352 } 1353 1354 static void handle_v_cont(GArray *params, void *user_ctx) 1355 { 1356 int res; 1357 1358 if (!params->len) { 1359 return; 1360 } 1361 1362 res = gdb_handle_vcont(get_param(params, 0)->data); 1363 if ((res == -EINVAL) || (res == -ERANGE)) { 1364 gdb_put_packet("E22"); 1365 } else if (res) { 1366 gdb_put_packet(""); 1367 } 1368 } 1369 1370 static void handle_v_attach(GArray *params, void *user_ctx) 1371 { 1372 GDBProcess *process; 1373 CPUState *cpu; 1374 1375 g_string_assign(gdbserver_state.str_buf, "E22"); 1376 if (!params->len) { 1377 goto cleanup; 1378 } 1379 1380 process = gdb_get_process(get_param(params, 0)->val_ul); 1381 if (!process) { 1382 goto cleanup; 1383 } 1384 1385 cpu = gdb_get_first_cpu_in_process(process); 1386 if (!cpu) { 1387 goto cleanup; 1388 } 1389 1390 process->attached = true; 1391 gdbserver_state.g_cpu = cpu; 1392 gdbserver_state.c_cpu = cpu; 1393 1394 if (gdbserver_state.allow_stop_reply) { 1395 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1396 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1397 g_string_append_c(gdbserver_state.str_buf, ';'); 1398 gdbserver_state.allow_stop_reply = false; 1399 cleanup: 1400 gdb_put_strbuf(); 1401 } 1402 } 1403 1404 static void handle_v_kill(GArray *params, void *user_ctx) 1405 { 1406 /* Kill the target */ 1407 gdb_put_packet("OK"); 1408 error_report("QEMU: Terminated via GDBstub"); 1409 gdb_exit(0); 1410 gdb_qemu_exit(0); 1411 } 1412 1413 static const GdbCmdParseEntry gdb_v_commands_table[] = { 1414 /* Order is important if has same prefix */ 1415 { 1416 .handler = handle_v_cont_query, 1417 .cmd = "Cont?", 1418 .cmd_startswith = 1 1419 }, 1420 { 1421 .handler = handle_v_cont, 1422 .cmd = "Cont", 1423 .cmd_startswith = 1, 1424 .allow_stop_reply = true, 1425 .schema = "s0" 1426 }, 1427 { 1428 .handler = handle_v_attach, 1429 .cmd = "Attach;", 1430 .cmd_startswith = 1, 1431 .allow_stop_reply = true, 1432 .schema = "l0" 1433 }, 1434 { 1435 .handler = handle_v_kill, 1436 .cmd = "Kill;", 1437 .cmd_startswith = 1 1438 }, 1439 #ifdef CONFIG_USER_ONLY 1440 /* 1441 * Host I/O Packets. See [1] for details. 1442 * [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html 1443 */ 1444 { 1445 .handler = gdb_handle_v_file_open, 1446 .cmd = "File:open:", 1447 .cmd_startswith = 1, 1448 .schema = "s,L,L0" 1449 }, 1450 { 1451 .handler = gdb_handle_v_file_close, 1452 .cmd = "File:close:", 1453 .cmd_startswith = 1, 1454 .schema = "l0" 1455 }, 1456 { 1457 .handler = gdb_handle_v_file_pread, 1458 .cmd = "File:pread:", 1459 .cmd_startswith = 1, 1460 .schema = "l,L,L0" 1461 }, 1462 { 1463 .handler = gdb_handle_v_file_readlink, 1464 .cmd = "File:readlink:", 1465 .cmd_startswith = 1, 1466 .schema = "s0" 1467 }, 1468 #endif 1469 }; 1470 1471 static void handle_v_commands(GArray *params, void *user_ctx) 1472 { 1473 if (!params->len) { 1474 return; 1475 } 1476 1477 if (process_string_cmd(get_param(params, 0)->data, 1478 gdb_v_commands_table, 1479 ARRAY_SIZE(gdb_v_commands_table))) { 1480 gdb_put_packet(""); 1481 } 1482 } 1483 1484 static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx) 1485 { 1486 g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE); 1487 1488 if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) { 1489 g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x", 1490 SSTEP_NOIRQ); 1491 } 1492 1493 if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) { 1494 g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x", 1495 SSTEP_NOTIMER); 1496 } 1497 1498 gdb_put_strbuf(); 1499 } 1500 1501 static void handle_set_qemu_sstep(GArray *params, void *user_ctx) 1502 { 1503 int new_sstep_flags; 1504 1505 if (!params->len) { 1506 return; 1507 } 1508 1509 new_sstep_flags = get_param(params, 0)->val_ul; 1510 1511 if (new_sstep_flags & ~gdbserver_state.supported_sstep_flags) { 1512 gdb_put_packet("E22"); 1513 return; 1514 } 1515 1516 gdbserver_state.sstep_flags = new_sstep_flags; 1517 gdb_put_packet("OK"); 1518 } 1519 1520 static void handle_query_qemu_sstep(GArray *params, void *user_ctx) 1521 { 1522 g_string_printf(gdbserver_state.str_buf, "0x%x", 1523 gdbserver_state.sstep_flags); 1524 gdb_put_strbuf(); 1525 } 1526 1527 static void handle_query_curr_tid(GArray *params, void *user_ctx) 1528 { 1529 CPUState *cpu; 1530 GDBProcess *process; 1531 1532 /* 1533 * "Current thread" remains vague in the spec, so always return 1534 * the first thread of the current process (gdb returns the 1535 * first thread). 1536 */ 1537 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1538 cpu = gdb_get_first_cpu_in_process(process); 1539 g_string_assign(gdbserver_state.str_buf, "QC"); 1540 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1541 gdb_put_strbuf(); 1542 } 1543 1544 static void handle_query_threads(GArray *params, void *user_ctx) 1545 { 1546 if (!gdbserver_state.query_cpu) { 1547 gdb_put_packet("l"); 1548 return; 1549 } 1550 1551 g_string_assign(gdbserver_state.str_buf, "m"); 1552 gdb_append_thread_id(gdbserver_state.query_cpu, gdbserver_state.str_buf); 1553 gdb_put_strbuf(); 1554 gdbserver_state.query_cpu = gdb_next_attached_cpu(gdbserver_state.query_cpu); 1555 } 1556 1557 static void handle_query_first_threads(GArray *params, void *user_ctx) 1558 { 1559 gdbserver_state.query_cpu = gdb_first_attached_cpu(); 1560 handle_query_threads(params, user_ctx); 1561 } 1562 1563 static void handle_query_thread_extra(GArray *params, void *user_ctx) 1564 { 1565 g_autoptr(GString) rs = g_string_new(NULL); 1566 CPUState *cpu; 1567 1568 if (!params->len || 1569 get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1570 gdb_put_packet("E22"); 1571 return; 1572 } 1573 1574 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1575 get_param(params, 0)->thread_id.tid); 1576 if (!cpu) { 1577 return; 1578 } 1579 1580 cpu_synchronize_state(cpu); 1581 1582 if (gdbserver_state.multiprocess && (gdbserver_state.process_num > 1)) { 1583 /* Print the CPU model and name in multiprocess mode */ 1584 ObjectClass *oc = object_get_class(OBJECT(cpu)); 1585 const char *cpu_model = object_class_get_name(oc); 1586 const char *cpu_name = 1587 object_get_canonical_path_component(OBJECT(cpu)); 1588 g_string_printf(rs, "%s %s [%s]", cpu_model, cpu_name, 1589 cpu->halted ? "halted " : "running"); 1590 } else { 1591 g_string_printf(rs, "CPU#%d [%s]", cpu->cpu_index, 1592 cpu->halted ? "halted " : "running"); 1593 } 1594 trace_gdbstub_op_extra_info(rs->str); 1595 gdb_memtohex(gdbserver_state.str_buf, (uint8_t *)rs->str, rs->len); 1596 gdb_put_strbuf(); 1597 } 1598 1599 static void handle_query_supported(GArray *params, void *user_ctx) 1600 { 1601 CPUClass *cc; 1602 1603 g_string_printf(gdbserver_state.str_buf, "PacketSize=%x", MAX_PACKET_LENGTH); 1604 cc = CPU_GET_CLASS(first_cpu); 1605 if (cc->gdb_core_xml_file) { 1606 g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+"); 1607 } 1608 1609 if (gdb_can_reverse()) { 1610 g_string_append(gdbserver_state.str_buf, 1611 ";ReverseStep+;ReverseContinue+"); 1612 } 1613 1614 #if defined(CONFIG_USER_ONLY) 1615 #if defined(CONFIG_LINUX) 1616 if (gdbserver_state.c_cpu->opaque) { 1617 g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+"); 1618 } 1619 g_string_append(gdbserver_state.str_buf, ";QCatchSyscalls+"); 1620 #endif 1621 g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+"); 1622 #endif 1623 1624 if (params->len && 1625 strstr(get_param(params, 0)->data, "multiprocess+")) { 1626 gdbserver_state.multiprocess = true; 1627 } 1628 1629 g_string_append(gdbserver_state.str_buf, ";vContSupported+;multiprocess+"); 1630 gdb_put_strbuf(); 1631 } 1632 1633 static void handle_query_xfer_features(GArray *params, void *user_ctx) 1634 { 1635 GDBProcess *process; 1636 CPUClass *cc; 1637 unsigned long len, total_len, addr; 1638 const char *xml; 1639 const char *p; 1640 1641 if (params->len < 3) { 1642 gdb_put_packet("E22"); 1643 return; 1644 } 1645 1646 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1647 cc = CPU_GET_CLASS(gdbserver_state.g_cpu); 1648 if (!cc->gdb_core_xml_file) { 1649 gdb_put_packet(""); 1650 return; 1651 } 1652 1653 p = get_param(params, 0)->data; 1654 xml = get_feature_xml(p, &p, process); 1655 if (!xml) { 1656 gdb_put_packet("E00"); 1657 return; 1658 } 1659 1660 addr = get_param(params, 1)->val_ul; 1661 len = get_param(params, 2)->val_ul; 1662 total_len = strlen(xml); 1663 if (addr > total_len) { 1664 gdb_put_packet("E00"); 1665 return; 1666 } 1667 1668 if (len > (MAX_PACKET_LENGTH - 5) / 2) { 1669 len = (MAX_PACKET_LENGTH - 5) / 2; 1670 } 1671 1672 if (len < total_len - addr) { 1673 g_string_assign(gdbserver_state.str_buf, "m"); 1674 gdb_memtox(gdbserver_state.str_buf, xml + addr, len); 1675 } else { 1676 g_string_assign(gdbserver_state.str_buf, "l"); 1677 gdb_memtox(gdbserver_state.str_buf, xml + addr, total_len - addr); 1678 } 1679 1680 gdb_put_packet_binary(gdbserver_state.str_buf->str, 1681 gdbserver_state.str_buf->len, true); 1682 } 1683 1684 static void handle_query_qemu_supported(GArray *params, void *user_ctx) 1685 { 1686 g_string_printf(gdbserver_state.str_buf, "sstepbits;sstep"); 1687 #ifndef CONFIG_USER_ONLY 1688 g_string_append(gdbserver_state.str_buf, ";PhyMemMode"); 1689 #endif 1690 gdb_put_strbuf(); 1691 } 1692 1693 static const GdbCmdParseEntry gdb_gen_query_set_common_table[] = { 1694 /* Order is important if has same prefix */ 1695 { 1696 .handler = handle_query_qemu_sstepbits, 1697 .cmd = "qemu.sstepbits", 1698 }, 1699 { 1700 .handler = handle_query_qemu_sstep, 1701 .cmd = "qemu.sstep", 1702 }, 1703 { 1704 .handler = handle_set_qemu_sstep, 1705 .cmd = "qemu.sstep=", 1706 .cmd_startswith = 1, 1707 .schema = "l0" 1708 }, 1709 }; 1710 1711 static const GdbCmdParseEntry gdb_gen_query_table[] = { 1712 { 1713 .handler = handle_query_curr_tid, 1714 .cmd = "C", 1715 }, 1716 { 1717 .handler = handle_query_threads, 1718 .cmd = "sThreadInfo", 1719 }, 1720 { 1721 .handler = handle_query_first_threads, 1722 .cmd = "fThreadInfo", 1723 }, 1724 { 1725 .handler = handle_query_thread_extra, 1726 .cmd = "ThreadExtraInfo,", 1727 .cmd_startswith = 1, 1728 .schema = "t0" 1729 }, 1730 #ifdef CONFIG_USER_ONLY 1731 { 1732 .handler = gdb_handle_query_offsets, 1733 .cmd = "Offsets", 1734 }, 1735 #else 1736 { 1737 .handler = gdb_handle_query_rcmd, 1738 .cmd = "Rcmd,", 1739 .cmd_startswith = 1, 1740 .schema = "s0" 1741 }, 1742 #endif 1743 { 1744 .handler = handle_query_supported, 1745 .cmd = "Supported:", 1746 .cmd_startswith = 1, 1747 .schema = "s0" 1748 }, 1749 { 1750 .handler = handle_query_supported, 1751 .cmd = "Supported", 1752 .schema = "s0" 1753 }, 1754 { 1755 .handler = handle_query_xfer_features, 1756 .cmd = "Xfer:features:read:", 1757 .cmd_startswith = 1, 1758 .schema = "s:l,l0" 1759 }, 1760 #if defined(CONFIG_USER_ONLY) 1761 #if defined(CONFIG_LINUX) 1762 { 1763 .handler = gdb_handle_query_xfer_auxv, 1764 .cmd = "Xfer:auxv:read::", 1765 .cmd_startswith = 1, 1766 .schema = "l,l0" 1767 }, 1768 #endif 1769 { 1770 .handler = gdb_handle_query_xfer_exec_file, 1771 .cmd = "Xfer:exec-file:read:", 1772 .cmd_startswith = 1, 1773 .schema = "l:l,l0" 1774 }, 1775 #endif 1776 { 1777 .handler = gdb_handle_query_attached, 1778 .cmd = "Attached:", 1779 .cmd_startswith = 1 1780 }, 1781 { 1782 .handler = gdb_handle_query_attached, 1783 .cmd = "Attached", 1784 }, 1785 { 1786 .handler = handle_query_qemu_supported, 1787 .cmd = "qemu.Supported", 1788 }, 1789 #ifndef CONFIG_USER_ONLY 1790 { 1791 .handler = gdb_handle_query_qemu_phy_mem_mode, 1792 .cmd = "qemu.PhyMemMode", 1793 }, 1794 #endif 1795 }; 1796 1797 static const GdbCmdParseEntry gdb_gen_set_table[] = { 1798 /* Order is important if has same prefix */ 1799 { 1800 .handler = handle_set_qemu_sstep, 1801 .cmd = "qemu.sstep:", 1802 .cmd_startswith = 1, 1803 .schema = "l0" 1804 }, 1805 #ifndef CONFIG_USER_ONLY 1806 { 1807 .handler = gdb_handle_set_qemu_phy_mem_mode, 1808 .cmd = "qemu.PhyMemMode:", 1809 .cmd_startswith = 1, 1810 .schema = "l0" 1811 }, 1812 #endif 1813 #if defined(CONFIG_USER_ONLY) 1814 { 1815 .handler = gdb_handle_set_catch_syscalls, 1816 .cmd = "CatchSyscalls:", 1817 .cmd_startswith = 1, 1818 .schema = "s0", 1819 }, 1820 #endif 1821 }; 1822 1823 static void handle_gen_query(GArray *params, void *user_ctx) 1824 { 1825 if (!params->len) { 1826 return; 1827 } 1828 1829 if (!process_string_cmd(get_param(params, 0)->data, 1830 gdb_gen_query_set_common_table, 1831 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1832 return; 1833 } 1834 1835 if (process_string_cmd(get_param(params, 0)->data, 1836 gdb_gen_query_table, 1837 ARRAY_SIZE(gdb_gen_query_table))) { 1838 gdb_put_packet(""); 1839 } 1840 } 1841 1842 static void handle_gen_set(GArray *params, void *user_ctx) 1843 { 1844 if (!params->len) { 1845 return; 1846 } 1847 1848 if (!process_string_cmd(get_param(params, 0)->data, 1849 gdb_gen_query_set_common_table, 1850 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1851 return; 1852 } 1853 1854 if (process_string_cmd(get_param(params, 0)->data, 1855 gdb_gen_set_table, 1856 ARRAY_SIZE(gdb_gen_set_table))) { 1857 gdb_put_packet(""); 1858 } 1859 } 1860 1861 static void handle_target_halt(GArray *params, void *user_ctx) 1862 { 1863 if (gdbserver_state.allow_stop_reply) { 1864 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1865 gdb_append_thread_id(gdbserver_state.c_cpu, gdbserver_state.str_buf); 1866 g_string_append_c(gdbserver_state.str_buf, ';'); 1867 gdb_put_strbuf(); 1868 gdbserver_state.allow_stop_reply = false; 1869 } 1870 /* 1871 * Remove all the breakpoints when this query is issued, 1872 * because gdb is doing an initial connect and the state 1873 * should be cleaned up. 1874 */ 1875 gdb_breakpoint_remove_all(gdbserver_state.c_cpu); 1876 } 1877 1878 static int gdb_handle_packet(const char *line_buf) 1879 { 1880 const GdbCmdParseEntry *cmd_parser = NULL; 1881 1882 trace_gdbstub_io_command(line_buf); 1883 1884 switch (line_buf[0]) { 1885 case '!': 1886 gdb_put_packet("OK"); 1887 break; 1888 case '?': 1889 { 1890 static const GdbCmdParseEntry target_halted_cmd_desc = { 1891 .handler = handle_target_halt, 1892 .cmd = "?", 1893 .cmd_startswith = 1, 1894 .allow_stop_reply = true, 1895 }; 1896 cmd_parser = &target_halted_cmd_desc; 1897 } 1898 break; 1899 case 'c': 1900 { 1901 static const GdbCmdParseEntry continue_cmd_desc = { 1902 .handler = handle_continue, 1903 .cmd = "c", 1904 .cmd_startswith = 1, 1905 .allow_stop_reply = true, 1906 .schema = "L0" 1907 }; 1908 cmd_parser = &continue_cmd_desc; 1909 } 1910 break; 1911 case 'C': 1912 { 1913 static const GdbCmdParseEntry cont_with_sig_cmd_desc = { 1914 .handler = handle_cont_with_sig, 1915 .cmd = "C", 1916 .cmd_startswith = 1, 1917 .allow_stop_reply = true, 1918 .schema = "l0" 1919 }; 1920 cmd_parser = &cont_with_sig_cmd_desc; 1921 } 1922 break; 1923 case 'v': 1924 { 1925 static const GdbCmdParseEntry v_cmd_desc = { 1926 .handler = handle_v_commands, 1927 .cmd = "v", 1928 .cmd_startswith = 1, 1929 .schema = "s0" 1930 }; 1931 cmd_parser = &v_cmd_desc; 1932 } 1933 break; 1934 case 'k': 1935 /* Kill the target */ 1936 error_report("QEMU: Terminated via GDBstub"); 1937 gdb_exit(0); 1938 gdb_qemu_exit(0); 1939 break; 1940 case 'D': 1941 { 1942 static const GdbCmdParseEntry detach_cmd_desc = { 1943 .handler = handle_detach, 1944 .cmd = "D", 1945 .cmd_startswith = 1, 1946 .schema = "?.l0" 1947 }; 1948 cmd_parser = &detach_cmd_desc; 1949 } 1950 break; 1951 case 's': 1952 { 1953 static const GdbCmdParseEntry step_cmd_desc = { 1954 .handler = handle_step, 1955 .cmd = "s", 1956 .cmd_startswith = 1, 1957 .allow_stop_reply = true, 1958 .schema = "L0" 1959 }; 1960 cmd_parser = &step_cmd_desc; 1961 } 1962 break; 1963 case 'b': 1964 { 1965 static const GdbCmdParseEntry backward_cmd_desc = { 1966 .handler = handle_backward, 1967 .cmd = "b", 1968 .cmd_startswith = 1, 1969 .allow_stop_reply = true, 1970 .schema = "o0" 1971 }; 1972 cmd_parser = &backward_cmd_desc; 1973 } 1974 break; 1975 case 'F': 1976 { 1977 static const GdbCmdParseEntry file_io_cmd_desc = { 1978 .handler = gdb_handle_file_io, 1979 .cmd = "F", 1980 .cmd_startswith = 1, 1981 .schema = "L,L,o0" 1982 }; 1983 cmd_parser = &file_io_cmd_desc; 1984 } 1985 break; 1986 case 'g': 1987 { 1988 static const GdbCmdParseEntry read_all_regs_cmd_desc = { 1989 .handler = handle_read_all_regs, 1990 .cmd = "g", 1991 .cmd_startswith = 1 1992 }; 1993 cmd_parser = &read_all_regs_cmd_desc; 1994 } 1995 break; 1996 case 'G': 1997 { 1998 static const GdbCmdParseEntry write_all_regs_cmd_desc = { 1999 .handler = handle_write_all_regs, 2000 .cmd = "G", 2001 .cmd_startswith = 1, 2002 .schema = "s0" 2003 }; 2004 cmd_parser = &write_all_regs_cmd_desc; 2005 } 2006 break; 2007 case 'm': 2008 { 2009 static const GdbCmdParseEntry read_mem_cmd_desc = { 2010 .handler = handle_read_mem, 2011 .cmd = "m", 2012 .cmd_startswith = 1, 2013 .schema = "L,L0" 2014 }; 2015 cmd_parser = &read_mem_cmd_desc; 2016 } 2017 break; 2018 case 'M': 2019 { 2020 static const GdbCmdParseEntry write_mem_cmd_desc = { 2021 .handler = handle_write_mem, 2022 .cmd = "M", 2023 .cmd_startswith = 1, 2024 .schema = "L,L:s0" 2025 }; 2026 cmd_parser = &write_mem_cmd_desc; 2027 } 2028 break; 2029 case 'p': 2030 { 2031 static const GdbCmdParseEntry get_reg_cmd_desc = { 2032 .handler = handle_get_reg, 2033 .cmd = "p", 2034 .cmd_startswith = 1, 2035 .schema = "L0" 2036 }; 2037 cmd_parser = &get_reg_cmd_desc; 2038 } 2039 break; 2040 case 'P': 2041 { 2042 static const GdbCmdParseEntry set_reg_cmd_desc = { 2043 .handler = handle_set_reg, 2044 .cmd = "P", 2045 .cmd_startswith = 1, 2046 .schema = "L?s0" 2047 }; 2048 cmd_parser = &set_reg_cmd_desc; 2049 } 2050 break; 2051 case 'Z': 2052 { 2053 static const GdbCmdParseEntry insert_bp_cmd_desc = { 2054 .handler = handle_insert_bp, 2055 .cmd = "Z", 2056 .cmd_startswith = 1, 2057 .schema = "l?L?L0" 2058 }; 2059 cmd_parser = &insert_bp_cmd_desc; 2060 } 2061 break; 2062 case 'z': 2063 { 2064 static const GdbCmdParseEntry remove_bp_cmd_desc = { 2065 .handler = handle_remove_bp, 2066 .cmd = "z", 2067 .cmd_startswith = 1, 2068 .schema = "l?L?L0" 2069 }; 2070 cmd_parser = &remove_bp_cmd_desc; 2071 } 2072 break; 2073 case 'H': 2074 { 2075 static const GdbCmdParseEntry set_thread_cmd_desc = { 2076 .handler = handle_set_thread, 2077 .cmd = "H", 2078 .cmd_startswith = 1, 2079 .schema = "o.t0" 2080 }; 2081 cmd_parser = &set_thread_cmd_desc; 2082 } 2083 break; 2084 case 'T': 2085 { 2086 static const GdbCmdParseEntry thread_alive_cmd_desc = { 2087 .handler = handle_thread_alive, 2088 .cmd = "T", 2089 .cmd_startswith = 1, 2090 .schema = "t0" 2091 }; 2092 cmd_parser = &thread_alive_cmd_desc; 2093 } 2094 break; 2095 case 'q': 2096 { 2097 static const GdbCmdParseEntry gen_query_cmd_desc = { 2098 .handler = handle_gen_query, 2099 .cmd = "q", 2100 .cmd_startswith = 1, 2101 .schema = "s0" 2102 }; 2103 cmd_parser = &gen_query_cmd_desc; 2104 } 2105 break; 2106 case 'Q': 2107 { 2108 static const GdbCmdParseEntry gen_set_cmd_desc = { 2109 .handler = handle_gen_set, 2110 .cmd = "Q", 2111 .cmd_startswith = 1, 2112 .schema = "s0" 2113 }; 2114 cmd_parser = &gen_set_cmd_desc; 2115 } 2116 break; 2117 default: 2118 /* put empty packet */ 2119 gdb_put_packet(""); 2120 break; 2121 } 2122 2123 if (cmd_parser) { 2124 run_cmd_parser(line_buf, cmd_parser); 2125 } 2126 2127 return RS_IDLE; 2128 } 2129 2130 void gdb_set_stop_cpu(CPUState *cpu) 2131 { 2132 GDBProcess *p = gdb_get_cpu_process(cpu); 2133 2134 if (!p->attached) { 2135 /* 2136 * Having a stop CPU corresponding to a process that is not attached 2137 * confuses GDB. So we ignore the request. 2138 */ 2139 return; 2140 } 2141 2142 gdbserver_state.c_cpu = cpu; 2143 gdbserver_state.g_cpu = cpu; 2144 } 2145 2146 void gdb_read_byte(uint8_t ch) 2147 { 2148 uint8_t reply; 2149 2150 gdbserver_state.allow_stop_reply = false; 2151 #ifndef CONFIG_USER_ONLY 2152 if (gdbserver_state.last_packet->len) { 2153 /* Waiting for a response to the last packet. If we see the start 2154 of a new command then abandon the previous response. */ 2155 if (ch == '-') { 2156 trace_gdbstub_err_got_nack(); 2157 gdb_put_buffer(gdbserver_state.last_packet->data, 2158 gdbserver_state.last_packet->len); 2159 } else if (ch == '+') { 2160 trace_gdbstub_io_got_ack(); 2161 } else { 2162 trace_gdbstub_io_got_unexpected(ch); 2163 } 2164 2165 if (ch == '+' || ch == '$') { 2166 g_byte_array_set_size(gdbserver_state.last_packet, 0); 2167 } 2168 if (ch != '$') 2169 return; 2170 } 2171 if (runstate_is_running()) { 2172 /* 2173 * When the CPU is running, we cannot do anything except stop 2174 * it when receiving a char. This is expected on a Ctrl-C in the 2175 * gdb client. Because we are in all-stop mode, gdb sends a 2176 * 0x03 byte which is not a usual packet, so we handle it specially 2177 * here, but it does expect a stop reply. 2178 */ 2179 if (ch != 0x03) { 2180 trace_gdbstub_err_unexpected_runpkt(ch); 2181 } else { 2182 gdbserver_state.allow_stop_reply = true; 2183 } 2184 vm_stop(RUN_STATE_PAUSED); 2185 } else 2186 #endif 2187 { 2188 switch(gdbserver_state.state) { 2189 case RS_IDLE: 2190 if (ch == '$') { 2191 /* start of command packet */ 2192 gdbserver_state.line_buf_index = 0; 2193 gdbserver_state.line_sum = 0; 2194 gdbserver_state.state = RS_GETLINE; 2195 } else if (ch == '+') { 2196 /* 2197 * do nothing, gdb may preemptively send out ACKs on 2198 * initial connection 2199 */ 2200 } else { 2201 trace_gdbstub_err_garbage(ch); 2202 } 2203 break; 2204 case RS_GETLINE: 2205 if (ch == '}') { 2206 /* start escape sequence */ 2207 gdbserver_state.state = RS_GETLINE_ESC; 2208 gdbserver_state.line_sum += ch; 2209 } else if (ch == '*') { 2210 /* start run length encoding sequence */ 2211 gdbserver_state.state = RS_GETLINE_RLE; 2212 gdbserver_state.line_sum += ch; 2213 } else if (ch == '#') { 2214 /* end of command, start of checksum*/ 2215 gdbserver_state.state = RS_CHKSUM1; 2216 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2217 trace_gdbstub_err_overrun(); 2218 gdbserver_state.state = RS_IDLE; 2219 } else { 2220 /* unescaped command character */ 2221 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch; 2222 gdbserver_state.line_sum += ch; 2223 } 2224 break; 2225 case RS_GETLINE_ESC: 2226 if (ch == '#') { 2227 /* unexpected end of command in escape sequence */ 2228 gdbserver_state.state = RS_CHKSUM1; 2229 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2230 /* command buffer overrun */ 2231 trace_gdbstub_err_overrun(); 2232 gdbserver_state.state = RS_IDLE; 2233 } else { 2234 /* parse escaped character and leave escape state */ 2235 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch ^ 0x20; 2236 gdbserver_state.line_sum += ch; 2237 gdbserver_state.state = RS_GETLINE; 2238 } 2239 break; 2240 case RS_GETLINE_RLE: 2241 /* 2242 * Run-length encoding is explained in "Debugging with GDB / 2243 * Appendix E GDB Remote Serial Protocol / Overview". 2244 */ 2245 if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) { 2246 /* invalid RLE count encoding */ 2247 trace_gdbstub_err_invalid_repeat(ch); 2248 gdbserver_state.state = RS_GETLINE; 2249 } else { 2250 /* decode repeat length */ 2251 int repeat = ch - ' ' + 3; 2252 if (gdbserver_state.line_buf_index + repeat >= sizeof(gdbserver_state.line_buf) - 1) { 2253 /* that many repeats would overrun the command buffer */ 2254 trace_gdbstub_err_overrun(); 2255 gdbserver_state.state = RS_IDLE; 2256 } else if (gdbserver_state.line_buf_index < 1) { 2257 /* got a repeat but we have nothing to repeat */ 2258 trace_gdbstub_err_invalid_rle(); 2259 gdbserver_state.state = RS_GETLINE; 2260 } else { 2261 /* repeat the last character */ 2262 memset(gdbserver_state.line_buf + gdbserver_state.line_buf_index, 2263 gdbserver_state.line_buf[gdbserver_state.line_buf_index - 1], repeat); 2264 gdbserver_state.line_buf_index += repeat; 2265 gdbserver_state.line_sum += ch; 2266 gdbserver_state.state = RS_GETLINE; 2267 } 2268 } 2269 break; 2270 case RS_CHKSUM1: 2271 /* get high hex digit of checksum */ 2272 if (!isxdigit(ch)) { 2273 trace_gdbstub_err_checksum_invalid(ch); 2274 gdbserver_state.state = RS_GETLINE; 2275 break; 2276 } 2277 gdbserver_state.line_buf[gdbserver_state.line_buf_index] = '\0'; 2278 gdbserver_state.line_csum = fromhex(ch) << 4; 2279 gdbserver_state.state = RS_CHKSUM2; 2280 break; 2281 case RS_CHKSUM2: 2282 /* get low hex digit of checksum */ 2283 if (!isxdigit(ch)) { 2284 trace_gdbstub_err_checksum_invalid(ch); 2285 gdbserver_state.state = RS_GETLINE; 2286 break; 2287 } 2288 gdbserver_state.line_csum |= fromhex(ch); 2289 2290 if (gdbserver_state.line_csum != (gdbserver_state.line_sum & 0xff)) { 2291 trace_gdbstub_err_checksum_incorrect(gdbserver_state.line_sum, gdbserver_state.line_csum); 2292 /* send NAK reply */ 2293 reply = '-'; 2294 gdb_put_buffer(&reply, 1); 2295 gdbserver_state.state = RS_IDLE; 2296 } else { 2297 /* send ACK reply */ 2298 reply = '+'; 2299 gdb_put_buffer(&reply, 1); 2300 gdbserver_state.state = gdb_handle_packet(gdbserver_state.line_buf); 2301 } 2302 break; 2303 default: 2304 abort(); 2305 } 2306 } 2307 } 2308 2309 /* 2310 * Create the process that will contain all the "orphan" CPUs (that are not 2311 * part of a CPU cluster). Note that if this process contains no CPUs, it won't 2312 * be attachable and thus will be invisible to the user. 2313 */ 2314 void gdb_create_default_process(GDBState *s) 2315 { 2316 GDBProcess *process; 2317 int pid; 2318 2319 #ifdef CONFIG_USER_ONLY 2320 assert(gdbserver_state.process_num == 0); 2321 pid = getpid(); 2322 #else 2323 if (gdbserver_state.process_num) { 2324 pid = s->processes[s->process_num - 1].pid; 2325 } else { 2326 pid = 0; 2327 } 2328 /* We need an available PID slot for this process */ 2329 assert(pid < UINT32_MAX); 2330 pid++; 2331 #endif 2332 2333 s->processes = g_renew(GDBProcess, s->processes, ++s->process_num); 2334 process = &s->processes[s->process_num - 1]; 2335 process->pid = pid; 2336 process->attached = false; 2337 process->target_xml = NULL; 2338 } 2339 2340