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->regs = g_ptr_array_new(); 423 builder->base_reg = base_reg; 424 feature->xmlname = xmlname; 425 feature->name = name; 426 } 427 428 void gdb_feature_builder_append_tag(const GDBFeatureBuilder *builder, 429 const char *format, ...) 430 { 431 va_list ap; 432 va_start(ap, format); 433 g_ptr_array_add(builder->xml, g_markup_vprintf_escaped(format, ap)); 434 va_end(ap); 435 } 436 437 void gdb_feature_builder_append_reg(const GDBFeatureBuilder *builder, 438 const char *name, 439 int bitsize, 440 int regnum, 441 const char *type, 442 const char *group) 443 { 444 if (builder->regs->len <= regnum) { 445 g_ptr_array_set_size(builder->regs, regnum + 1); 446 } 447 448 builder->regs->pdata[regnum] = (gpointer *)name; 449 450 if (group) { 451 gdb_feature_builder_append_tag( 452 builder, 453 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\" group=\"%s\"/>", 454 name, bitsize, builder->base_reg + regnum, type, group); 455 } else { 456 gdb_feature_builder_append_tag( 457 builder, 458 "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\"/>", 459 name, bitsize, builder->base_reg + regnum, type); 460 } 461 } 462 463 void gdb_feature_builder_end(const GDBFeatureBuilder *builder) 464 { 465 g_ptr_array_add(builder->xml, (void *)"</feature>"); 466 g_ptr_array_add(builder->xml, NULL); 467 468 builder->feature->xml = g_strjoinv(NULL, (void *)builder->xml->pdata); 469 470 for (guint i = 0; i < builder->xml->len - 2; i++) { 471 g_free(g_ptr_array_index(builder->xml, i)); 472 } 473 474 g_ptr_array_free(builder->xml, TRUE); 475 476 builder->feature->num_regs = builder->regs->len; 477 builder->feature->regs = (void *)g_ptr_array_free(builder->regs, FALSE); 478 } 479 480 const GDBFeature *gdb_find_static_feature(const char *xmlname) 481 { 482 const GDBFeature *feature; 483 484 for (feature = gdb_static_features; feature->xmlname; feature++) { 485 if (!strcmp(feature->xmlname, xmlname)) { 486 return feature; 487 } 488 } 489 490 g_assert_not_reached(); 491 } 492 493 GArray *gdb_get_register_list(CPUState *cpu) 494 { 495 GArray *results = g_array_new(true, true, sizeof(GDBRegDesc)); 496 497 /* registers are only available once the CPU is initialised */ 498 if (!cpu->gdb_regs) { 499 return results; 500 } 501 502 for (int f = 0; f < cpu->gdb_regs->len; f++) { 503 GDBRegisterState *r = &g_array_index(cpu->gdb_regs, GDBRegisterState, f); 504 for (int i = 0; i < r->feature->num_regs; i++) { 505 const char *name = r->feature->regs[i]; 506 GDBRegDesc desc = { 507 r->base_reg + i, 508 name, 509 r->feature->name 510 }; 511 g_array_append_val(results, desc); 512 } 513 } 514 515 return results; 516 } 517 518 int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg) 519 { 520 CPUClass *cc = CPU_GET_CLASS(cpu); 521 GDBRegisterState *r; 522 523 if (reg < cc->gdb_num_core_regs) { 524 return cc->gdb_read_register(cpu, buf, reg); 525 } 526 527 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 528 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 529 if (r->base_reg <= reg && reg < r->base_reg + r->feature->num_regs) { 530 return r->get_reg(cpu, buf, reg - r->base_reg); 531 } 532 } 533 return 0; 534 } 535 536 static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg) 537 { 538 CPUClass *cc = CPU_GET_CLASS(cpu); 539 GDBRegisterState *r; 540 541 if (reg < cc->gdb_num_core_regs) { 542 return cc->gdb_write_register(cpu, mem_buf, reg); 543 } 544 545 for (guint i = 0; i < cpu->gdb_regs->len; i++) { 546 r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 547 if (r->base_reg <= reg && reg < r->base_reg + r->feature->num_regs) { 548 return r->set_reg(cpu, mem_buf, reg - r->base_reg); 549 } 550 } 551 return 0; 552 } 553 554 static void gdb_register_feature(CPUState *cpu, int base_reg, 555 gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg, 556 const GDBFeature *feature) 557 { 558 GDBRegisterState s = { 559 .base_reg = base_reg, 560 .get_reg = get_reg, 561 .set_reg = set_reg, 562 .feature = feature 563 }; 564 565 g_array_append_val(cpu->gdb_regs, s); 566 } 567 568 void gdb_init_cpu(CPUState *cpu) 569 { 570 CPUClass *cc = CPU_GET_CLASS(cpu); 571 const GDBFeature *feature; 572 573 cpu->gdb_regs = g_array_new(false, false, sizeof(GDBRegisterState)); 574 575 if (cc->gdb_core_xml_file) { 576 feature = gdb_find_static_feature(cc->gdb_core_xml_file); 577 gdb_register_feature(cpu, 0, 578 cc->gdb_read_register, cc->gdb_write_register, 579 feature); 580 cpu->gdb_num_regs = cpu->gdb_num_g_regs = feature->num_regs; 581 } 582 583 if (cc->gdb_num_core_regs) { 584 cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs; 585 } 586 } 587 588 void gdb_register_coprocessor(CPUState *cpu, 589 gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg, 590 const GDBFeature *feature, int g_pos) 591 { 592 GDBRegisterState *s; 593 guint i; 594 int base_reg = cpu->gdb_num_regs; 595 596 for (i = 0; i < cpu->gdb_regs->len; i++) { 597 /* Check for duplicates. */ 598 s = &g_array_index(cpu->gdb_regs, GDBRegisterState, i); 599 if (s->feature == feature) { 600 return; 601 } 602 } 603 604 gdb_register_feature(cpu, base_reg, get_reg, set_reg, feature); 605 606 /* Add to end of list. */ 607 cpu->gdb_num_regs += feature->num_regs; 608 if (g_pos) { 609 if (g_pos != base_reg) { 610 error_report("Error: Bad gdb register numbering for '%s', " 611 "expected %d got %d", feature->xml, g_pos, base_reg); 612 } else { 613 cpu->gdb_num_g_regs = cpu->gdb_num_regs; 614 } 615 } 616 } 617 618 static void gdb_process_breakpoint_remove_all(GDBProcess *p) 619 { 620 CPUState *cpu = gdb_get_first_cpu_in_process(p); 621 622 while (cpu) { 623 gdb_breakpoint_remove_all(cpu); 624 cpu = gdb_next_cpu_in_process(cpu); 625 } 626 } 627 628 629 static void gdb_set_cpu_pc(vaddr pc) 630 { 631 CPUState *cpu = gdbserver_state.c_cpu; 632 633 cpu_synchronize_state(cpu); 634 cpu_set_pc(cpu, pc); 635 } 636 637 void gdb_append_thread_id(CPUState *cpu, GString *buf) 638 { 639 if (gdbserver_state.multiprocess) { 640 g_string_append_printf(buf, "p%02x.%02x", 641 gdb_get_cpu_pid(cpu), gdb_get_cpu_index(cpu)); 642 } else { 643 g_string_append_printf(buf, "%02x", gdb_get_cpu_index(cpu)); 644 } 645 } 646 647 static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf, 648 uint32_t *pid, uint32_t *tid) 649 { 650 unsigned long p, t; 651 int ret; 652 653 if (*buf == 'p') { 654 buf++; 655 ret = qemu_strtoul(buf, &buf, 16, &p); 656 657 if (ret) { 658 return GDB_READ_THREAD_ERR; 659 } 660 661 /* Skip '.' */ 662 buf++; 663 } else { 664 p = 0; 665 } 666 667 ret = qemu_strtoul(buf, &buf, 16, &t); 668 669 if (ret) { 670 return GDB_READ_THREAD_ERR; 671 } 672 673 *end_buf = buf; 674 675 if (p == -1) { 676 return GDB_ALL_PROCESSES; 677 } 678 679 if (pid) { 680 *pid = p; 681 } 682 683 if (t == -1) { 684 return GDB_ALL_THREADS; 685 } 686 687 if (tid) { 688 *tid = t; 689 } 690 691 return GDB_ONE_THREAD; 692 } 693 694 /** 695 * gdb_handle_vcont - Parses and handles a vCont packet. 696 * returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is 697 * a format error, 0 on success. 698 */ 699 static int gdb_handle_vcont(const char *p) 700 { 701 int res, signal = 0; 702 char cur_action; 703 unsigned long tmp; 704 uint32_t pid, tid; 705 GDBProcess *process; 706 CPUState *cpu; 707 GDBThreadIdKind kind; 708 unsigned int max_cpus = gdb_get_max_cpus(); 709 /* uninitialised CPUs stay 0 */ 710 g_autofree char *newstates = g_new0(char, max_cpus); 711 712 /* mark valid CPUs with 1 */ 713 CPU_FOREACH(cpu) { 714 newstates[cpu->cpu_index] = 1; 715 } 716 717 /* 718 * res keeps track of what error we are returning, with -ENOTSUP meaning 719 * that the command is unknown or unsupported, thus returning an empty 720 * packet, while -EINVAL and -ERANGE cause an E22 packet, due to invalid, 721 * or incorrect parameters passed. 722 */ 723 res = 0; 724 725 /* 726 * target_count and last_target keep track of how many CPUs we are going to 727 * step or resume, and a pointer to the state structure of one of them, 728 * respectively 729 */ 730 int target_count = 0; 731 CPUState *last_target = NULL; 732 733 while (*p) { 734 if (*p++ != ';') { 735 return -ENOTSUP; 736 } 737 738 cur_action = *p++; 739 if (cur_action == 'C' || cur_action == 'S') { 740 cur_action = qemu_tolower(cur_action); 741 res = qemu_strtoul(p, &p, 16, &tmp); 742 if (res) { 743 return res; 744 } 745 signal = gdb_signal_to_target(tmp); 746 } else if (cur_action != 'c' && cur_action != 's') { 747 /* unknown/invalid/unsupported command */ 748 return -ENOTSUP; 749 } 750 751 if (*p == '\0' || *p == ';') { 752 /* 753 * No thread specifier, action is on "all threads". The 754 * specification is unclear regarding the process to act on. We 755 * choose all processes. 756 */ 757 kind = GDB_ALL_PROCESSES; 758 } else if (*p++ == ':') { 759 kind = read_thread_id(p, &p, &pid, &tid); 760 } else { 761 return -ENOTSUP; 762 } 763 764 switch (kind) { 765 case GDB_READ_THREAD_ERR: 766 return -EINVAL; 767 768 case GDB_ALL_PROCESSES: 769 cpu = gdb_first_attached_cpu(); 770 while (cpu) { 771 if (newstates[cpu->cpu_index] == 1) { 772 newstates[cpu->cpu_index] = cur_action; 773 774 target_count++; 775 last_target = cpu; 776 } 777 778 cpu = gdb_next_attached_cpu(cpu); 779 } 780 break; 781 782 case GDB_ALL_THREADS: 783 process = gdb_get_process(pid); 784 785 if (!process->attached) { 786 return -EINVAL; 787 } 788 789 cpu = gdb_get_first_cpu_in_process(process); 790 while (cpu) { 791 if (newstates[cpu->cpu_index] == 1) { 792 newstates[cpu->cpu_index] = cur_action; 793 794 target_count++; 795 last_target = cpu; 796 } 797 798 cpu = gdb_next_cpu_in_process(cpu); 799 } 800 break; 801 802 case GDB_ONE_THREAD: 803 cpu = gdb_get_cpu(pid, tid); 804 805 /* invalid CPU/thread specified */ 806 if (!cpu) { 807 return -EINVAL; 808 } 809 810 /* only use if no previous match occourred */ 811 if (newstates[cpu->cpu_index] == 1) { 812 newstates[cpu->cpu_index] = cur_action; 813 814 target_count++; 815 last_target = cpu; 816 } 817 break; 818 } 819 } 820 821 /* 822 * if we're about to resume a specific set of CPUs/threads, make it so that 823 * in case execution gets interrupted, we can send GDB a stop reply with a 824 * correct value. it doesn't really matter which CPU we tell GDB the signal 825 * happened in (VM pauses stop all of them anyway), so long as it is one of 826 * the ones we resumed/single stepped here. 827 */ 828 if (target_count > 0) { 829 gdbserver_state.c_cpu = last_target; 830 } 831 832 gdbserver_state.signal = signal; 833 gdb_continue_partial(newstates); 834 return res; 835 } 836 837 static const char *cmd_next_param(const char *param, const char delimiter) 838 { 839 static const char all_delimiters[] = ",;:="; 840 char curr_delimiters[2] = {0}; 841 const char *delimiters; 842 843 if (delimiter == '?') { 844 delimiters = all_delimiters; 845 } else if (delimiter == '0') { 846 return strchr(param, '\0'); 847 } else if (delimiter == '.' && *param) { 848 return param + 1; 849 } else { 850 curr_delimiters[0] = delimiter; 851 delimiters = curr_delimiters; 852 } 853 854 param += strcspn(param, delimiters); 855 if (*param) { 856 param++; 857 } 858 return param; 859 } 860 861 static int cmd_parse_params(const char *data, const char *schema, 862 GArray *params) 863 { 864 const char *curr_schema, *curr_data; 865 866 g_assert(schema); 867 g_assert(params->len == 0); 868 869 curr_schema = schema; 870 curr_data = data; 871 while (curr_schema[0] && curr_schema[1] && *curr_data) { 872 GdbCmdVariant this_param; 873 874 switch (curr_schema[0]) { 875 case 'l': 876 if (qemu_strtoul(curr_data, &curr_data, 16, 877 &this_param.val_ul)) { 878 return -EINVAL; 879 } 880 curr_data = cmd_next_param(curr_data, curr_schema[1]); 881 g_array_append_val(params, this_param); 882 break; 883 case 'L': 884 if (qemu_strtou64(curr_data, &curr_data, 16, 885 (uint64_t *)&this_param.val_ull)) { 886 return -EINVAL; 887 } 888 curr_data = cmd_next_param(curr_data, curr_schema[1]); 889 g_array_append_val(params, this_param); 890 break; 891 case 's': 892 this_param.data = curr_data; 893 curr_data = cmd_next_param(curr_data, curr_schema[1]); 894 g_array_append_val(params, this_param); 895 break; 896 case 'o': 897 this_param.opcode = *(uint8_t *)curr_data; 898 curr_data = cmd_next_param(curr_data, curr_schema[1]); 899 g_array_append_val(params, this_param); 900 break; 901 case 't': 902 this_param.thread_id.kind = 903 read_thread_id(curr_data, &curr_data, 904 &this_param.thread_id.pid, 905 &this_param.thread_id.tid); 906 curr_data = cmd_next_param(curr_data, curr_schema[1]); 907 g_array_append_val(params, this_param); 908 break; 909 case '?': 910 curr_data = cmd_next_param(curr_data, curr_schema[1]); 911 break; 912 default: 913 return -EINVAL; 914 } 915 curr_schema += 2; 916 } 917 918 return 0; 919 } 920 921 typedef void (*GdbCmdHandler)(GArray *params, void *user_ctx); 922 923 /* 924 * cmd_startswith -> cmd is compared using startswith 925 * 926 * allow_stop_reply -> true iff the gdbstub can respond to this command with a 927 * "stop reply" packet. The list of commands that accept such response is 928 * defined at the GDB Remote Serial Protocol documentation. see: 929 * https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets. 930 * 931 * schema definitions: 932 * Each schema parameter entry consists of 2 chars, 933 * the first char represents the parameter type handling 934 * the second char represents the delimiter for the next parameter 935 * 936 * Currently supported schema types: 937 * 'l' -> unsigned long (stored in .val_ul) 938 * 'L' -> unsigned long long (stored in .val_ull) 939 * 's' -> string (stored in .data) 940 * 'o' -> single char (stored in .opcode) 941 * 't' -> thread id (stored in .thread_id) 942 * '?' -> skip according to delimiter 943 * 944 * Currently supported delimiters: 945 * '?' -> Stop at any delimiter (",;:=\0") 946 * '0' -> Stop at "\0" 947 * '.' -> Skip 1 char unless reached "\0" 948 * Any other value is treated as the delimiter value itself 949 */ 950 typedef struct GdbCmdParseEntry { 951 GdbCmdHandler handler; 952 const char *cmd; 953 bool cmd_startswith; 954 const char *schema; 955 bool allow_stop_reply; 956 } GdbCmdParseEntry; 957 958 static inline int startswith(const char *string, const char *pattern) 959 { 960 return !strncmp(string, pattern, strlen(pattern)); 961 } 962 963 static int process_string_cmd(const char *data, 964 const GdbCmdParseEntry *cmds, int num_cmds) 965 { 966 int i; 967 g_autoptr(GArray) params = g_array_new(false, true, sizeof(GdbCmdVariant)); 968 969 if (!cmds) { 970 return -1; 971 } 972 973 for (i = 0; i < num_cmds; i++) { 974 const GdbCmdParseEntry *cmd = &cmds[i]; 975 g_assert(cmd->handler && cmd->cmd); 976 977 if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) || 978 (!cmd->cmd_startswith && strcmp(cmd->cmd, data))) { 979 continue; 980 } 981 982 if (cmd->schema) { 983 if (cmd_parse_params(&data[strlen(cmd->cmd)], 984 cmd->schema, params)) { 985 return -1; 986 } 987 } 988 989 gdbserver_state.allow_stop_reply = cmd->allow_stop_reply; 990 cmd->handler(params, NULL); 991 return 0; 992 } 993 994 return -1; 995 } 996 997 static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd) 998 { 999 if (!data) { 1000 return; 1001 } 1002 1003 g_string_set_size(gdbserver_state.str_buf, 0); 1004 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 1005 1006 /* In case there was an error during the command parsing we must 1007 * send a NULL packet to indicate the command is not supported */ 1008 if (process_string_cmd(data, cmd, 1)) { 1009 gdb_put_packet(""); 1010 } 1011 } 1012 1013 static void handle_detach(GArray *params, void *user_ctx) 1014 { 1015 GDBProcess *process; 1016 uint32_t pid = 1; 1017 1018 if (gdbserver_state.multiprocess) { 1019 if (!params->len) { 1020 gdb_put_packet("E22"); 1021 return; 1022 } 1023 1024 pid = get_param(params, 0)->val_ul; 1025 } 1026 1027 #ifdef CONFIG_USER_ONLY 1028 if (gdb_handle_detach_user(pid)) { 1029 return; 1030 } 1031 #endif 1032 1033 process = gdb_get_process(pid); 1034 gdb_process_breakpoint_remove_all(process); 1035 process->attached = false; 1036 1037 if (pid == gdb_get_cpu_pid(gdbserver_state.c_cpu)) { 1038 gdbserver_state.c_cpu = gdb_first_attached_cpu(); 1039 } 1040 1041 if (pid == gdb_get_cpu_pid(gdbserver_state.g_cpu)) { 1042 gdbserver_state.g_cpu = gdb_first_attached_cpu(); 1043 } 1044 1045 if (!gdbserver_state.c_cpu) { 1046 /* No more process attached */ 1047 gdb_disable_syscalls(); 1048 gdb_continue(); 1049 } 1050 gdb_put_packet("OK"); 1051 } 1052 1053 static void handle_thread_alive(GArray *params, void *user_ctx) 1054 { 1055 CPUState *cpu; 1056 1057 if (!params->len) { 1058 gdb_put_packet("E22"); 1059 return; 1060 } 1061 1062 if (get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1063 gdb_put_packet("E22"); 1064 return; 1065 } 1066 1067 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1068 get_param(params, 0)->thread_id.tid); 1069 if (!cpu) { 1070 gdb_put_packet("E22"); 1071 return; 1072 } 1073 1074 gdb_put_packet("OK"); 1075 } 1076 1077 static void handle_continue(GArray *params, void *user_ctx) 1078 { 1079 if (params->len) { 1080 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1081 } 1082 1083 gdbserver_state.signal = 0; 1084 gdb_continue(); 1085 } 1086 1087 static void handle_cont_with_sig(GArray *params, void *user_ctx) 1088 { 1089 unsigned long signal = 0; 1090 1091 /* 1092 * Note: C sig;[addr] is currently unsupported and we simply 1093 * omit the addr parameter 1094 */ 1095 if (params->len) { 1096 signal = get_param(params, 0)->val_ul; 1097 } 1098 1099 gdbserver_state.signal = gdb_signal_to_target(signal); 1100 if (gdbserver_state.signal == -1) { 1101 gdbserver_state.signal = 0; 1102 } 1103 gdb_continue(); 1104 } 1105 1106 static void handle_set_thread(GArray *params, void *user_ctx) 1107 { 1108 uint32_t pid, tid; 1109 CPUState *cpu; 1110 1111 if (params->len != 2) { 1112 gdb_put_packet("E22"); 1113 return; 1114 } 1115 1116 if (get_param(params, 1)->thread_id.kind == GDB_READ_THREAD_ERR) { 1117 gdb_put_packet("E22"); 1118 return; 1119 } 1120 1121 if (get_param(params, 1)->thread_id.kind != GDB_ONE_THREAD) { 1122 gdb_put_packet("OK"); 1123 return; 1124 } 1125 1126 pid = get_param(params, 1)->thread_id.pid; 1127 tid = get_param(params, 1)->thread_id.tid; 1128 #ifdef CONFIG_USER_ONLY 1129 if (gdb_handle_set_thread_user(pid, tid)) { 1130 return; 1131 } 1132 #endif 1133 cpu = gdb_get_cpu(pid, tid); 1134 if (!cpu) { 1135 gdb_put_packet("E22"); 1136 return; 1137 } 1138 1139 /* 1140 * Note: This command is deprecated and modern gdb's will be using the 1141 * vCont command instead. 1142 */ 1143 switch (get_param(params, 0)->opcode) { 1144 case 'c': 1145 gdbserver_state.c_cpu = cpu; 1146 gdb_put_packet("OK"); 1147 break; 1148 case 'g': 1149 gdbserver_state.g_cpu = cpu; 1150 gdb_put_packet("OK"); 1151 break; 1152 default: 1153 gdb_put_packet("E22"); 1154 break; 1155 } 1156 } 1157 1158 static void handle_insert_bp(GArray *params, void *user_ctx) 1159 { 1160 int res; 1161 1162 if (params->len != 3) { 1163 gdb_put_packet("E22"); 1164 return; 1165 } 1166 1167 res = gdb_breakpoint_insert(gdbserver_state.c_cpu, 1168 get_param(params, 0)->val_ul, 1169 get_param(params, 1)->val_ull, 1170 get_param(params, 2)->val_ull); 1171 if (res >= 0) { 1172 gdb_put_packet("OK"); 1173 return; 1174 } else if (res == -ENOSYS) { 1175 gdb_put_packet(""); 1176 return; 1177 } 1178 1179 gdb_put_packet("E22"); 1180 } 1181 1182 static void handle_remove_bp(GArray *params, void *user_ctx) 1183 { 1184 int res; 1185 1186 if (params->len != 3) { 1187 gdb_put_packet("E22"); 1188 return; 1189 } 1190 1191 res = gdb_breakpoint_remove(gdbserver_state.c_cpu, 1192 get_param(params, 0)->val_ul, 1193 get_param(params, 1)->val_ull, 1194 get_param(params, 2)->val_ull); 1195 if (res >= 0) { 1196 gdb_put_packet("OK"); 1197 return; 1198 } else if (res == -ENOSYS) { 1199 gdb_put_packet(""); 1200 return; 1201 } 1202 1203 gdb_put_packet("E22"); 1204 } 1205 1206 /* 1207 * handle_set/get_reg 1208 * 1209 * Older gdb are really dumb, and don't use 'G/g' if 'P/p' is available. 1210 * This works, but can be very slow. Anything new enough to understand 1211 * XML also knows how to use this properly. However to use this we 1212 * need to define a local XML file as well as be talking to a 1213 * reasonably modern gdb. Responding with an empty packet will cause 1214 * the remote gdb to fallback to older methods. 1215 */ 1216 1217 static void handle_set_reg(GArray *params, void *user_ctx) 1218 { 1219 int reg_size; 1220 1221 if (params->len != 2) { 1222 gdb_put_packet("E22"); 1223 return; 1224 } 1225 1226 reg_size = strlen(get_param(params, 1)->data) / 2; 1227 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, reg_size); 1228 gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data, 1229 get_param(params, 0)->val_ull); 1230 gdb_put_packet("OK"); 1231 } 1232 1233 static void handle_get_reg(GArray *params, void *user_ctx) 1234 { 1235 int reg_size; 1236 1237 if (!params->len) { 1238 gdb_put_packet("E14"); 1239 return; 1240 } 1241 1242 reg_size = gdb_read_register(gdbserver_state.g_cpu, 1243 gdbserver_state.mem_buf, 1244 get_param(params, 0)->val_ull); 1245 if (!reg_size) { 1246 gdb_put_packet("E14"); 1247 return; 1248 } else { 1249 g_byte_array_set_size(gdbserver_state.mem_buf, reg_size); 1250 } 1251 1252 gdb_memtohex(gdbserver_state.str_buf, 1253 gdbserver_state.mem_buf->data, reg_size); 1254 gdb_put_strbuf(); 1255 } 1256 1257 static void handle_write_mem(GArray *params, void *user_ctx) 1258 { 1259 if (params->len != 3) { 1260 gdb_put_packet("E22"); 1261 return; 1262 } 1263 1264 /* gdb_hextomem() reads 2*len bytes */ 1265 if (get_param(params, 1)->val_ull > 1266 strlen(get_param(params, 2)->data) / 2) { 1267 gdb_put_packet("E22"); 1268 return; 1269 } 1270 1271 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 2)->data, 1272 get_param(params, 1)->val_ull); 1273 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1274 get_param(params, 0)->val_ull, 1275 gdbserver_state.mem_buf->data, 1276 gdbserver_state.mem_buf->len, true)) { 1277 gdb_put_packet("E14"); 1278 return; 1279 } 1280 1281 gdb_put_packet("OK"); 1282 } 1283 1284 static void handle_read_mem(GArray *params, void *user_ctx) 1285 { 1286 if (params->len != 2) { 1287 gdb_put_packet("E22"); 1288 return; 1289 } 1290 1291 /* gdb_memtohex() doubles the required space */ 1292 if (get_param(params, 1)->val_ull > MAX_PACKET_LENGTH / 2) { 1293 gdb_put_packet("E22"); 1294 return; 1295 } 1296 1297 g_byte_array_set_size(gdbserver_state.mem_buf, 1298 get_param(params, 1)->val_ull); 1299 1300 if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu, 1301 get_param(params, 0)->val_ull, 1302 gdbserver_state.mem_buf->data, 1303 gdbserver_state.mem_buf->len, false)) { 1304 gdb_put_packet("E14"); 1305 return; 1306 } 1307 1308 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, 1309 gdbserver_state.mem_buf->len); 1310 gdb_put_strbuf(); 1311 } 1312 1313 static void handle_write_all_regs(GArray *params, void *user_ctx) 1314 { 1315 int reg_id; 1316 size_t len; 1317 uint8_t *registers; 1318 int reg_size; 1319 1320 if (!params->len) { 1321 return; 1322 } 1323 1324 cpu_synchronize_state(gdbserver_state.g_cpu); 1325 len = strlen(get_param(params, 0)->data) / 2; 1326 gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 0)->data, len); 1327 registers = gdbserver_state.mem_buf->data; 1328 for (reg_id = 0; 1329 reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0; 1330 reg_id++) { 1331 reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id); 1332 len -= reg_size; 1333 registers += reg_size; 1334 } 1335 gdb_put_packet("OK"); 1336 } 1337 1338 static void handle_read_all_regs(GArray *params, void *user_ctx) 1339 { 1340 int reg_id; 1341 size_t len; 1342 1343 cpu_synchronize_state(gdbserver_state.g_cpu); 1344 g_byte_array_set_size(gdbserver_state.mem_buf, 0); 1345 len = 0; 1346 for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) { 1347 len += gdb_read_register(gdbserver_state.g_cpu, 1348 gdbserver_state.mem_buf, 1349 reg_id); 1350 } 1351 g_assert(len == gdbserver_state.mem_buf->len); 1352 1353 gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len); 1354 gdb_put_strbuf(); 1355 } 1356 1357 1358 static void handle_step(GArray *params, void *user_ctx) 1359 { 1360 if (params->len) { 1361 gdb_set_cpu_pc(get_param(params, 0)->val_ull); 1362 } 1363 1364 cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags); 1365 gdb_continue(); 1366 } 1367 1368 static void handle_backward(GArray *params, void *user_ctx) 1369 { 1370 if (!gdb_can_reverse()) { 1371 gdb_put_packet("E22"); 1372 } 1373 if (params->len == 1) { 1374 switch (get_param(params, 0)->opcode) { 1375 case 's': 1376 if (replay_reverse_step()) { 1377 gdb_continue(); 1378 } else { 1379 gdb_put_packet("E14"); 1380 } 1381 return; 1382 case 'c': 1383 if (replay_reverse_continue()) { 1384 gdb_continue(); 1385 } else { 1386 gdb_put_packet("E14"); 1387 } 1388 return; 1389 } 1390 } 1391 1392 /* Default invalid command */ 1393 gdb_put_packet(""); 1394 } 1395 1396 static void handle_v_cont_query(GArray *params, void *user_ctx) 1397 { 1398 gdb_put_packet("vCont;c;C;s;S"); 1399 } 1400 1401 static void handle_v_cont(GArray *params, void *user_ctx) 1402 { 1403 int res; 1404 1405 if (!params->len) { 1406 return; 1407 } 1408 1409 res = gdb_handle_vcont(get_param(params, 0)->data); 1410 if ((res == -EINVAL) || (res == -ERANGE)) { 1411 gdb_put_packet("E22"); 1412 } else if (res) { 1413 gdb_put_packet(""); 1414 } 1415 } 1416 1417 static void handle_v_attach(GArray *params, void *user_ctx) 1418 { 1419 GDBProcess *process; 1420 CPUState *cpu; 1421 1422 g_string_assign(gdbserver_state.str_buf, "E22"); 1423 if (!params->len) { 1424 goto cleanup; 1425 } 1426 1427 process = gdb_get_process(get_param(params, 0)->val_ul); 1428 if (!process) { 1429 goto cleanup; 1430 } 1431 1432 cpu = gdb_get_first_cpu_in_process(process); 1433 if (!cpu) { 1434 goto cleanup; 1435 } 1436 1437 process->attached = true; 1438 gdbserver_state.g_cpu = cpu; 1439 gdbserver_state.c_cpu = cpu; 1440 1441 if (gdbserver_state.allow_stop_reply) { 1442 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1443 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1444 g_string_append_c(gdbserver_state.str_buf, ';'); 1445 gdbserver_state.allow_stop_reply = false; 1446 cleanup: 1447 gdb_put_strbuf(); 1448 } 1449 } 1450 1451 static void handle_v_kill(GArray *params, void *user_ctx) 1452 { 1453 /* Kill the target */ 1454 gdb_put_packet("OK"); 1455 error_report("QEMU: Terminated via GDBstub"); 1456 gdb_exit(0); 1457 gdb_qemu_exit(0); 1458 } 1459 1460 static const GdbCmdParseEntry gdb_v_commands_table[] = { 1461 /* Order is important if has same prefix */ 1462 { 1463 .handler = handle_v_cont_query, 1464 .cmd = "Cont?", 1465 .cmd_startswith = 1 1466 }, 1467 { 1468 .handler = handle_v_cont, 1469 .cmd = "Cont", 1470 .cmd_startswith = 1, 1471 .allow_stop_reply = true, 1472 .schema = "s0" 1473 }, 1474 { 1475 .handler = handle_v_attach, 1476 .cmd = "Attach;", 1477 .cmd_startswith = 1, 1478 .allow_stop_reply = true, 1479 .schema = "l0" 1480 }, 1481 { 1482 .handler = handle_v_kill, 1483 .cmd = "Kill;", 1484 .cmd_startswith = 1 1485 }, 1486 #ifdef CONFIG_USER_ONLY 1487 /* 1488 * Host I/O Packets. See [1] for details. 1489 * [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html 1490 */ 1491 { 1492 .handler = gdb_handle_v_file_open, 1493 .cmd = "File:open:", 1494 .cmd_startswith = 1, 1495 .schema = "s,L,L0" 1496 }, 1497 { 1498 .handler = gdb_handle_v_file_close, 1499 .cmd = "File:close:", 1500 .cmd_startswith = 1, 1501 .schema = "l0" 1502 }, 1503 { 1504 .handler = gdb_handle_v_file_pread, 1505 .cmd = "File:pread:", 1506 .cmd_startswith = 1, 1507 .schema = "l,L,L0" 1508 }, 1509 { 1510 .handler = gdb_handle_v_file_readlink, 1511 .cmd = "File:readlink:", 1512 .cmd_startswith = 1, 1513 .schema = "s0" 1514 }, 1515 #endif 1516 }; 1517 1518 static void handle_v_commands(GArray *params, void *user_ctx) 1519 { 1520 if (!params->len) { 1521 return; 1522 } 1523 1524 if (process_string_cmd(get_param(params, 0)->data, 1525 gdb_v_commands_table, 1526 ARRAY_SIZE(gdb_v_commands_table))) { 1527 gdb_put_packet(""); 1528 } 1529 } 1530 1531 static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx) 1532 { 1533 g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE); 1534 1535 if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) { 1536 g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x", 1537 SSTEP_NOIRQ); 1538 } 1539 1540 if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) { 1541 g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x", 1542 SSTEP_NOTIMER); 1543 } 1544 1545 gdb_put_strbuf(); 1546 } 1547 1548 static void handle_set_qemu_sstep(GArray *params, void *user_ctx) 1549 { 1550 int new_sstep_flags; 1551 1552 if (!params->len) { 1553 return; 1554 } 1555 1556 new_sstep_flags = get_param(params, 0)->val_ul; 1557 1558 if (new_sstep_flags & ~gdbserver_state.supported_sstep_flags) { 1559 gdb_put_packet("E22"); 1560 return; 1561 } 1562 1563 gdbserver_state.sstep_flags = new_sstep_flags; 1564 gdb_put_packet("OK"); 1565 } 1566 1567 static void handle_query_qemu_sstep(GArray *params, void *user_ctx) 1568 { 1569 g_string_printf(gdbserver_state.str_buf, "0x%x", 1570 gdbserver_state.sstep_flags); 1571 gdb_put_strbuf(); 1572 } 1573 1574 static void handle_query_curr_tid(GArray *params, void *user_ctx) 1575 { 1576 CPUState *cpu; 1577 GDBProcess *process; 1578 1579 /* 1580 * "Current thread" remains vague in the spec, so always return 1581 * the first thread of the current process (gdb returns the 1582 * first thread). 1583 */ 1584 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1585 cpu = gdb_get_first_cpu_in_process(process); 1586 g_string_assign(gdbserver_state.str_buf, "QC"); 1587 gdb_append_thread_id(cpu, gdbserver_state.str_buf); 1588 gdb_put_strbuf(); 1589 } 1590 1591 static void handle_query_threads(GArray *params, void *user_ctx) 1592 { 1593 if (!gdbserver_state.query_cpu) { 1594 gdb_put_packet("l"); 1595 return; 1596 } 1597 1598 g_string_assign(gdbserver_state.str_buf, "m"); 1599 gdb_append_thread_id(gdbserver_state.query_cpu, gdbserver_state.str_buf); 1600 gdb_put_strbuf(); 1601 gdbserver_state.query_cpu = gdb_next_attached_cpu(gdbserver_state.query_cpu); 1602 } 1603 1604 static void handle_query_first_threads(GArray *params, void *user_ctx) 1605 { 1606 gdbserver_state.query_cpu = gdb_first_attached_cpu(); 1607 handle_query_threads(params, user_ctx); 1608 } 1609 1610 static void handle_query_thread_extra(GArray *params, void *user_ctx) 1611 { 1612 g_autoptr(GString) rs = g_string_new(NULL); 1613 CPUState *cpu; 1614 1615 if (!params->len || 1616 get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) { 1617 gdb_put_packet("E22"); 1618 return; 1619 } 1620 1621 cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid, 1622 get_param(params, 0)->thread_id.tid); 1623 if (!cpu) { 1624 return; 1625 } 1626 1627 cpu_synchronize_state(cpu); 1628 1629 if (gdbserver_state.multiprocess && (gdbserver_state.process_num > 1)) { 1630 /* Print the CPU model and name in multiprocess mode */ 1631 ObjectClass *oc = object_get_class(OBJECT(cpu)); 1632 const char *cpu_model = object_class_get_name(oc); 1633 const char *cpu_name = 1634 object_get_canonical_path_component(OBJECT(cpu)); 1635 g_string_printf(rs, "%s %s [%s]", cpu_model, cpu_name, 1636 cpu->halted ? "halted " : "running"); 1637 } else { 1638 g_string_printf(rs, "CPU#%d [%s]", cpu->cpu_index, 1639 cpu->halted ? "halted " : "running"); 1640 } 1641 trace_gdbstub_op_extra_info(rs->str); 1642 gdb_memtohex(gdbserver_state.str_buf, (uint8_t *)rs->str, rs->len); 1643 gdb_put_strbuf(); 1644 } 1645 1646 static void handle_query_supported(GArray *params, void *user_ctx) 1647 { 1648 CPUClass *cc; 1649 1650 g_string_printf(gdbserver_state.str_buf, "PacketSize=%x", MAX_PACKET_LENGTH); 1651 cc = CPU_GET_CLASS(first_cpu); 1652 if (cc->gdb_core_xml_file) { 1653 g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+"); 1654 } 1655 1656 if (gdb_can_reverse()) { 1657 g_string_append(gdbserver_state.str_buf, 1658 ";ReverseStep+;ReverseContinue+"); 1659 } 1660 1661 #if defined(CONFIG_USER_ONLY) 1662 #if defined(CONFIG_LINUX) 1663 if (gdbserver_state.c_cpu->opaque) { 1664 g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+"); 1665 } 1666 g_string_append(gdbserver_state.str_buf, ";QCatchSyscalls+"); 1667 1668 g_string_append(gdbserver_state.str_buf, ";qXfer:siginfo:read+"); 1669 #endif 1670 g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+"); 1671 #endif 1672 1673 if (params->len) { 1674 const char *gdb_supported = get_param(params, 0)->data; 1675 1676 if (strstr(gdb_supported, "multiprocess+")) { 1677 gdbserver_state.multiprocess = true; 1678 } 1679 #if defined(CONFIG_USER_ONLY) 1680 gdb_handle_query_supported_user(gdb_supported); 1681 #endif 1682 } 1683 1684 g_string_append(gdbserver_state.str_buf, ";vContSupported+;multiprocess+"); 1685 gdb_put_strbuf(); 1686 } 1687 1688 static void handle_query_xfer_features(GArray *params, void *user_ctx) 1689 { 1690 GDBProcess *process; 1691 CPUClass *cc; 1692 unsigned long len, total_len, addr; 1693 const char *xml; 1694 const char *p; 1695 1696 if (params->len < 3) { 1697 gdb_put_packet("E22"); 1698 return; 1699 } 1700 1701 process = gdb_get_cpu_process(gdbserver_state.g_cpu); 1702 cc = CPU_GET_CLASS(gdbserver_state.g_cpu); 1703 if (!cc->gdb_core_xml_file) { 1704 gdb_put_packet(""); 1705 return; 1706 } 1707 1708 p = get_param(params, 0)->data; 1709 xml = get_feature_xml(p, &p, process); 1710 if (!xml) { 1711 gdb_put_packet("E00"); 1712 return; 1713 } 1714 1715 addr = get_param(params, 1)->val_ul; 1716 len = get_param(params, 2)->val_ul; 1717 total_len = strlen(xml); 1718 if (addr > total_len) { 1719 gdb_put_packet("E00"); 1720 return; 1721 } 1722 1723 if (len > (MAX_PACKET_LENGTH - 5) / 2) { 1724 len = (MAX_PACKET_LENGTH - 5) / 2; 1725 } 1726 1727 if (len < total_len - addr) { 1728 g_string_assign(gdbserver_state.str_buf, "m"); 1729 gdb_memtox(gdbserver_state.str_buf, xml + addr, len); 1730 } else { 1731 g_string_assign(gdbserver_state.str_buf, "l"); 1732 gdb_memtox(gdbserver_state.str_buf, xml + addr, total_len - addr); 1733 } 1734 1735 gdb_put_packet_binary(gdbserver_state.str_buf->str, 1736 gdbserver_state.str_buf->len, true); 1737 } 1738 1739 static void handle_query_qemu_supported(GArray *params, void *user_ctx) 1740 { 1741 g_string_printf(gdbserver_state.str_buf, "sstepbits;sstep"); 1742 #ifndef CONFIG_USER_ONLY 1743 g_string_append(gdbserver_state.str_buf, ";PhyMemMode"); 1744 #endif 1745 gdb_put_strbuf(); 1746 } 1747 1748 static const GdbCmdParseEntry gdb_gen_query_set_common_table[] = { 1749 /* Order is important if has same prefix */ 1750 { 1751 .handler = handle_query_qemu_sstepbits, 1752 .cmd = "qemu.sstepbits", 1753 }, 1754 { 1755 .handler = handle_query_qemu_sstep, 1756 .cmd = "qemu.sstep", 1757 }, 1758 { 1759 .handler = handle_set_qemu_sstep, 1760 .cmd = "qemu.sstep=", 1761 .cmd_startswith = 1, 1762 .schema = "l0" 1763 }, 1764 }; 1765 1766 static const GdbCmdParseEntry gdb_gen_query_table[] = { 1767 { 1768 .handler = handle_query_curr_tid, 1769 .cmd = "C", 1770 }, 1771 { 1772 .handler = handle_query_threads, 1773 .cmd = "sThreadInfo", 1774 }, 1775 { 1776 .handler = handle_query_first_threads, 1777 .cmd = "fThreadInfo", 1778 }, 1779 { 1780 .handler = handle_query_thread_extra, 1781 .cmd = "ThreadExtraInfo,", 1782 .cmd_startswith = 1, 1783 .schema = "t0" 1784 }, 1785 #ifdef CONFIG_USER_ONLY 1786 { 1787 .handler = gdb_handle_query_offsets, 1788 .cmd = "Offsets", 1789 }, 1790 #else 1791 { 1792 .handler = gdb_handle_query_rcmd, 1793 .cmd = "Rcmd,", 1794 .cmd_startswith = 1, 1795 .schema = "s0" 1796 }, 1797 #endif 1798 { 1799 .handler = handle_query_supported, 1800 .cmd = "Supported:", 1801 .cmd_startswith = 1, 1802 .schema = "s0" 1803 }, 1804 { 1805 .handler = handle_query_supported, 1806 .cmd = "Supported", 1807 .schema = "s0" 1808 }, 1809 { 1810 .handler = handle_query_xfer_features, 1811 .cmd = "Xfer:features:read:", 1812 .cmd_startswith = 1, 1813 .schema = "s:l,l0" 1814 }, 1815 #if defined(CONFIG_USER_ONLY) 1816 #if defined(CONFIG_LINUX) 1817 { 1818 .handler = gdb_handle_query_xfer_auxv, 1819 .cmd = "Xfer:auxv:read::", 1820 .cmd_startswith = 1, 1821 .schema = "l,l0" 1822 }, 1823 { 1824 .handler = gdb_handle_query_xfer_siginfo, 1825 .cmd = "Xfer:siginfo:read::", 1826 .cmd_startswith = 1, 1827 .schema = "l,l0" 1828 }, 1829 #endif 1830 { 1831 .handler = gdb_handle_query_xfer_exec_file, 1832 .cmd = "Xfer:exec-file:read:", 1833 .cmd_startswith = 1, 1834 .schema = "l:l,l0" 1835 }, 1836 #endif 1837 { 1838 .handler = gdb_handle_query_attached, 1839 .cmd = "Attached:", 1840 .cmd_startswith = 1 1841 }, 1842 { 1843 .handler = gdb_handle_query_attached, 1844 .cmd = "Attached", 1845 }, 1846 { 1847 .handler = handle_query_qemu_supported, 1848 .cmd = "qemu.Supported", 1849 }, 1850 #ifndef CONFIG_USER_ONLY 1851 { 1852 .handler = gdb_handle_query_qemu_phy_mem_mode, 1853 .cmd = "qemu.PhyMemMode", 1854 }, 1855 #endif 1856 }; 1857 1858 static const GdbCmdParseEntry gdb_gen_set_table[] = { 1859 /* Order is important if has same prefix */ 1860 { 1861 .handler = handle_set_qemu_sstep, 1862 .cmd = "qemu.sstep:", 1863 .cmd_startswith = 1, 1864 .schema = "l0" 1865 }, 1866 #ifndef CONFIG_USER_ONLY 1867 { 1868 .handler = gdb_handle_set_qemu_phy_mem_mode, 1869 .cmd = "qemu.PhyMemMode:", 1870 .cmd_startswith = 1, 1871 .schema = "l0" 1872 }, 1873 #endif 1874 #if defined(CONFIG_USER_ONLY) 1875 { 1876 .handler = gdb_handle_set_catch_syscalls, 1877 .cmd = "CatchSyscalls:", 1878 .cmd_startswith = 1, 1879 .schema = "s0", 1880 }, 1881 #endif 1882 }; 1883 1884 static void handle_gen_query(GArray *params, void *user_ctx) 1885 { 1886 if (!params->len) { 1887 return; 1888 } 1889 1890 if (!process_string_cmd(get_param(params, 0)->data, 1891 gdb_gen_query_set_common_table, 1892 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1893 return; 1894 } 1895 1896 if (process_string_cmd(get_param(params, 0)->data, 1897 gdb_gen_query_table, 1898 ARRAY_SIZE(gdb_gen_query_table))) { 1899 gdb_put_packet(""); 1900 } 1901 } 1902 1903 static void handle_gen_set(GArray *params, void *user_ctx) 1904 { 1905 if (!params->len) { 1906 return; 1907 } 1908 1909 if (!process_string_cmd(get_param(params, 0)->data, 1910 gdb_gen_query_set_common_table, 1911 ARRAY_SIZE(gdb_gen_query_set_common_table))) { 1912 return; 1913 } 1914 1915 if (process_string_cmd(get_param(params, 0)->data, 1916 gdb_gen_set_table, 1917 ARRAY_SIZE(gdb_gen_set_table))) { 1918 gdb_put_packet(""); 1919 } 1920 } 1921 1922 static void handle_target_halt(GArray *params, void *user_ctx) 1923 { 1924 if (gdbserver_state.allow_stop_reply) { 1925 g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP); 1926 gdb_append_thread_id(gdbserver_state.c_cpu, gdbserver_state.str_buf); 1927 g_string_append_c(gdbserver_state.str_buf, ';'); 1928 gdb_put_strbuf(); 1929 gdbserver_state.allow_stop_reply = false; 1930 } 1931 /* 1932 * Remove all the breakpoints when this query is issued, 1933 * because gdb is doing an initial connect and the state 1934 * should be cleaned up. 1935 */ 1936 gdb_breakpoint_remove_all(gdbserver_state.c_cpu); 1937 } 1938 1939 static int gdb_handle_packet(const char *line_buf) 1940 { 1941 const GdbCmdParseEntry *cmd_parser = NULL; 1942 1943 trace_gdbstub_io_command(line_buf); 1944 1945 switch (line_buf[0]) { 1946 case '!': 1947 gdb_put_packet("OK"); 1948 break; 1949 case '?': 1950 { 1951 static const GdbCmdParseEntry target_halted_cmd_desc = { 1952 .handler = handle_target_halt, 1953 .cmd = "?", 1954 .cmd_startswith = 1, 1955 .allow_stop_reply = true, 1956 }; 1957 cmd_parser = &target_halted_cmd_desc; 1958 } 1959 break; 1960 case 'c': 1961 { 1962 static const GdbCmdParseEntry continue_cmd_desc = { 1963 .handler = handle_continue, 1964 .cmd = "c", 1965 .cmd_startswith = 1, 1966 .allow_stop_reply = true, 1967 .schema = "L0" 1968 }; 1969 cmd_parser = &continue_cmd_desc; 1970 } 1971 break; 1972 case 'C': 1973 { 1974 static const GdbCmdParseEntry cont_with_sig_cmd_desc = { 1975 .handler = handle_cont_with_sig, 1976 .cmd = "C", 1977 .cmd_startswith = 1, 1978 .allow_stop_reply = true, 1979 .schema = "l0" 1980 }; 1981 cmd_parser = &cont_with_sig_cmd_desc; 1982 } 1983 break; 1984 case 'v': 1985 { 1986 static const GdbCmdParseEntry v_cmd_desc = { 1987 .handler = handle_v_commands, 1988 .cmd = "v", 1989 .cmd_startswith = 1, 1990 .schema = "s0" 1991 }; 1992 cmd_parser = &v_cmd_desc; 1993 } 1994 break; 1995 case 'k': 1996 /* Kill the target */ 1997 error_report("QEMU: Terminated via GDBstub"); 1998 gdb_exit(0); 1999 gdb_qemu_exit(0); 2000 break; 2001 case 'D': 2002 { 2003 static const GdbCmdParseEntry detach_cmd_desc = { 2004 .handler = handle_detach, 2005 .cmd = "D", 2006 .cmd_startswith = 1, 2007 .schema = "?.l0" 2008 }; 2009 cmd_parser = &detach_cmd_desc; 2010 } 2011 break; 2012 case 's': 2013 { 2014 static const GdbCmdParseEntry step_cmd_desc = { 2015 .handler = handle_step, 2016 .cmd = "s", 2017 .cmd_startswith = 1, 2018 .allow_stop_reply = true, 2019 .schema = "L0" 2020 }; 2021 cmd_parser = &step_cmd_desc; 2022 } 2023 break; 2024 case 'b': 2025 { 2026 static const GdbCmdParseEntry backward_cmd_desc = { 2027 .handler = handle_backward, 2028 .cmd = "b", 2029 .cmd_startswith = 1, 2030 .allow_stop_reply = true, 2031 .schema = "o0" 2032 }; 2033 cmd_parser = &backward_cmd_desc; 2034 } 2035 break; 2036 case 'F': 2037 { 2038 static const GdbCmdParseEntry file_io_cmd_desc = { 2039 .handler = gdb_handle_file_io, 2040 .cmd = "F", 2041 .cmd_startswith = 1, 2042 .schema = "L,L,o0" 2043 }; 2044 cmd_parser = &file_io_cmd_desc; 2045 } 2046 break; 2047 case 'g': 2048 { 2049 static const GdbCmdParseEntry read_all_regs_cmd_desc = { 2050 .handler = handle_read_all_regs, 2051 .cmd = "g", 2052 .cmd_startswith = 1 2053 }; 2054 cmd_parser = &read_all_regs_cmd_desc; 2055 } 2056 break; 2057 case 'G': 2058 { 2059 static const GdbCmdParseEntry write_all_regs_cmd_desc = { 2060 .handler = handle_write_all_regs, 2061 .cmd = "G", 2062 .cmd_startswith = 1, 2063 .schema = "s0" 2064 }; 2065 cmd_parser = &write_all_regs_cmd_desc; 2066 } 2067 break; 2068 case 'm': 2069 { 2070 static const GdbCmdParseEntry read_mem_cmd_desc = { 2071 .handler = handle_read_mem, 2072 .cmd = "m", 2073 .cmd_startswith = 1, 2074 .schema = "L,L0" 2075 }; 2076 cmd_parser = &read_mem_cmd_desc; 2077 } 2078 break; 2079 case 'M': 2080 { 2081 static const GdbCmdParseEntry write_mem_cmd_desc = { 2082 .handler = handle_write_mem, 2083 .cmd = "M", 2084 .cmd_startswith = 1, 2085 .schema = "L,L:s0" 2086 }; 2087 cmd_parser = &write_mem_cmd_desc; 2088 } 2089 break; 2090 case 'p': 2091 { 2092 static const GdbCmdParseEntry get_reg_cmd_desc = { 2093 .handler = handle_get_reg, 2094 .cmd = "p", 2095 .cmd_startswith = 1, 2096 .schema = "L0" 2097 }; 2098 cmd_parser = &get_reg_cmd_desc; 2099 } 2100 break; 2101 case 'P': 2102 { 2103 static const GdbCmdParseEntry set_reg_cmd_desc = { 2104 .handler = handle_set_reg, 2105 .cmd = "P", 2106 .cmd_startswith = 1, 2107 .schema = "L?s0" 2108 }; 2109 cmd_parser = &set_reg_cmd_desc; 2110 } 2111 break; 2112 case 'Z': 2113 { 2114 static const GdbCmdParseEntry insert_bp_cmd_desc = { 2115 .handler = handle_insert_bp, 2116 .cmd = "Z", 2117 .cmd_startswith = 1, 2118 .schema = "l?L?L0" 2119 }; 2120 cmd_parser = &insert_bp_cmd_desc; 2121 } 2122 break; 2123 case 'z': 2124 { 2125 static const GdbCmdParseEntry remove_bp_cmd_desc = { 2126 .handler = handle_remove_bp, 2127 .cmd = "z", 2128 .cmd_startswith = 1, 2129 .schema = "l?L?L0" 2130 }; 2131 cmd_parser = &remove_bp_cmd_desc; 2132 } 2133 break; 2134 case 'H': 2135 { 2136 static const GdbCmdParseEntry set_thread_cmd_desc = { 2137 .handler = handle_set_thread, 2138 .cmd = "H", 2139 .cmd_startswith = 1, 2140 .schema = "o.t0" 2141 }; 2142 cmd_parser = &set_thread_cmd_desc; 2143 } 2144 break; 2145 case 'T': 2146 { 2147 static const GdbCmdParseEntry thread_alive_cmd_desc = { 2148 .handler = handle_thread_alive, 2149 .cmd = "T", 2150 .cmd_startswith = 1, 2151 .schema = "t0" 2152 }; 2153 cmd_parser = &thread_alive_cmd_desc; 2154 } 2155 break; 2156 case 'q': 2157 { 2158 static const GdbCmdParseEntry gen_query_cmd_desc = { 2159 .handler = handle_gen_query, 2160 .cmd = "q", 2161 .cmd_startswith = 1, 2162 .schema = "s0" 2163 }; 2164 cmd_parser = &gen_query_cmd_desc; 2165 } 2166 break; 2167 case 'Q': 2168 { 2169 static const GdbCmdParseEntry gen_set_cmd_desc = { 2170 .handler = handle_gen_set, 2171 .cmd = "Q", 2172 .cmd_startswith = 1, 2173 .schema = "s0" 2174 }; 2175 cmd_parser = &gen_set_cmd_desc; 2176 } 2177 break; 2178 default: 2179 /* put empty packet */ 2180 gdb_put_packet(""); 2181 break; 2182 } 2183 2184 if (cmd_parser) { 2185 run_cmd_parser(line_buf, cmd_parser); 2186 } 2187 2188 return RS_IDLE; 2189 } 2190 2191 void gdb_set_stop_cpu(CPUState *cpu) 2192 { 2193 GDBProcess *p = gdb_get_cpu_process(cpu); 2194 2195 if (!p->attached) { 2196 /* 2197 * Having a stop CPU corresponding to a process that is not attached 2198 * confuses GDB. So we ignore the request. 2199 */ 2200 return; 2201 } 2202 2203 gdbserver_state.c_cpu = cpu; 2204 gdbserver_state.g_cpu = cpu; 2205 } 2206 2207 void gdb_read_byte(uint8_t ch) 2208 { 2209 uint8_t reply; 2210 2211 gdbserver_state.allow_stop_reply = false; 2212 #ifndef CONFIG_USER_ONLY 2213 if (gdbserver_state.last_packet->len) { 2214 /* Waiting for a response to the last packet. If we see the start 2215 of a new command then abandon the previous response. */ 2216 if (ch == '-') { 2217 trace_gdbstub_err_got_nack(); 2218 gdb_put_buffer(gdbserver_state.last_packet->data, 2219 gdbserver_state.last_packet->len); 2220 } else if (ch == '+') { 2221 trace_gdbstub_io_got_ack(); 2222 } else { 2223 trace_gdbstub_io_got_unexpected(ch); 2224 } 2225 2226 if (ch == '+' || ch == '$') { 2227 g_byte_array_set_size(gdbserver_state.last_packet, 0); 2228 } 2229 if (ch != '$') 2230 return; 2231 } 2232 if (runstate_is_running()) { 2233 /* 2234 * When the CPU is running, we cannot do anything except stop 2235 * it when receiving a char. This is expected on a Ctrl-C in the 2236 * gdb client. Because we are in all-stop mode, gdb sends a 2237 * 0x03 byte which is not a usual packet, so we handle it specially 2238 * here, but it does expect a stop reply. 2239 */ 2240 if (ch != 0x03) { 2241 trace_gdbstub_err_unexpected_runpkt(ch); 2242 } else { 2243 gdbserver_state.allow_stop_reply = true; 2244 } 2245 vm_stop(RUN_STATE_PAUSED); 2246 } else 2247 #endif 2248 { 2249 switch(gdbserver_state.state) { 2250 case RS_IDLE: 2251 if (ch == '$') { 2252 /* start of command packet */ 2253 gdbserver_state.line_buf_index = 0; 2254 gdbserver_state.line_sum = 0; 2255 gdbserver_state.state = RS_GETLINE; 2256 } else if (ch == '+') { 2257 /* 2258 * do nothing, gdb may preemptively send out ACKs on 2259 * initial connection 2260 */ 2261 } else { 2262 trace_gdbstub_err_garbage(ch); 2263 } 2264 break; 2265 case RS_GETLINE: 2266 if (ch == '}') { 2267 /* start escape sequence */ 2268 gdbserver_state.state = RS_GETLINE_ESC; 2269 gdbserver_state.line_sum += ch; 2270 } else if (ch == '*') { 2271 /* start run length encoding sequence */ 2272 gdbserver_state.state = RS_GETLINE_RLE; 2273 gdbserver_state.line_sum += ch; 2274 } else if (ch == '#') { 2275 /* end of command, start of checksum*/ 2276 gdbserver_state.state = RS_CHKSUM1; 2277 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2278 trace_gdbstub_err_overrun(); 2279 gdbserver_state.state = RS_IDLE; 2280 } else { 2281 /* unescaped command character */ 2282 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch; 2283 gdbserver_state.line_sum += ch; 2284 } 2285 break; 2286 case RS_GETLINE_ESC: 2287 if (ch == '#') { 2288 /* unexpected end of command in escape sequence */ 2289 gdbserver_state.state = RS_CHKSUM1; 2290 } else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) { 2291 /* command buffer overrun */ 2292 trace_gdbstub_err_overrun(); 2293 gdbserver_state.state = RS_IDLE; 2294 } else { 2295 /* parse escaped character and leave escape state */ 2296 gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch ^ 0x20; 2297 gdbserver_state.line_sum += ch; 2298 gdbserver_state.state = RS_GETLINE; 2299 } 2300 break; 2301 case RS_GETLINE_RLE: 2302 /* 2303 * Run-length encoding is explained in "Debugging with GDB / 2304 * Appendix E GDB Remote Serial Protocol / Overview". 2305 */ 2306 if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) { 2307 /* invalid RLE count encoding */ 2308 trace_gdbstub_err_invalid_repeat(ch); 2309 gdbserver_state.state = RS_GETLINE; 2310 } else { 2311 /* decode repeat length */ 2312 int repeat = ch - ' ' + 3; 2313 if (gdbserver_state.line_buf_index + repeat >= sizeof(gdbserver_state.line_buf) - 1) { 2314 /* that many repeats would overrun the command buffer */ 2315 trace_gdbstub_err_overrun(); 2316 gdbserver_state.state = RS_IDLE; 2317 } else if (gdbserver_state.line_buf_index < 1) { 2318 /* got a repeat but we have nothing to repeat */ 2319 trace_gdbstub_err_invalid_rle(); 2320 gdbserver_state.state = RS_GETLINE; 2321 } else { 2322 /* repeat the last character */ 2323 memset(gdbserver_state.line_buf + gdbserver_state.line_buf_index, 2324 gdbserver_state.line_buf[gdbserver_state.line_buf_index - 1], repeat); 2325 gdbserver_state.line_buf_index += repeat; 2326 gdbserver_state.line_sum += ch; 2327 gdbserver_state.state = RS_GETLINE; 2328 } 2329 } 2330 break; 2331 case RS_CHKSUM1: 2332 /* get high hex digit of checksum */ 2333 if (!isxdigit(ch)) { 2334 trace_gdbstub_err_checksum_invalid(ch); 2335 gdbserver_state.state = RS_GETLINE; 2336 break; 2337 } 2338 gdbserver_state.line_buf[gdbserver_state.line_buf_index] = '\0'; 2339 gdbserver_state.line_csum = fromhex(ch) << 4; 2340 gdbserver_state.state = RS_CHKSUM2; 2341 break; 2342 case RS_CHKSUM2: 2343 /* get low hex digit of checksum */ 2344 if (!isxdigit(ch)) { 2345 trace_gdbstub_err_checksum_invalid(ch); 2346 gdbserver_state.state = RS_GETLINE; 2347 break; 2348 } 2349 gdbserver_state.line_csum |= fromhex(ch); 2350 2351 if (gdbserver_state.line_csum != (gdbserver_state.line_sum & 0xff)) { 2352 trace_gdbstub_err_checksum_incorrect(gdbserver_state.line_sum, gdbserver_state.line_csum); 2353 /* send NAK reply */ 2354 reply = '-'; 2355 gdb_put_buffer(&reply, 1); 2356 gdbserver_state.state = RS_IDLE; 2357 } else { 2358 /* send ACK reply */ 2359 reply = '+'; 2360 gdb_put_buffer(&reply, 1); 2361 gdbserver_state.state = gdb_handle_packet(gdbserver_state.line_buf); 2362 } 2363 break; 2364 default: 2365 abort(); 2366 } 2367 } 2368 } 2369 2370 /* 2371 * Create the process that will contain all the "orphan" CPUs (that are not 2372 * part of a CPU cluster). Note that if this process contains no CPUs, it won't 2373 * be attachable and thus will be invisible to the user. 2374 */ 2375 void gdb_create_default_process(GDBState *s) 2376 { 2377 GDBProcess *process; 2378 int pid; 2379 2380 #ifdef CONFIG_USER_ONLY 2381 assert(gdbserver_state.process_num == 0); 2382 pid = getpid(); 2383 #else 2384 if (gdbserver_state.process_num) { 2385 pid = s->processes[s->process_num - 1].pid; 2386 } else { 2387 pid = 0; 2388 } 2389 /* We need an available PID slot for this process */ 2390 assert(pid < UINT32_MAX); 2391 pid++; 2392 #endif 2393 2394 s->processes = g_renew(GDBProcess, s->processes, ++s->process_num); 2395 process = &s->processes[s->process_num - 1]; 2396 process->pid = pid; 2397 process->attached = false; 2398 process->target_xml = NULL; 2399 } 2400 2401