remote_gdb.cc revision 12031:46116545e745
1/* 2 * Copyright 2015 LabWare 3 * Copyright 2014 Google, Inc. 4 * Copyright (c) 2002-2005 The Regents of The University of Michigan 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer; 11 * redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution; 14 * neither the name of the copyright holders nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * Authors: Nathan Binkert 31 * Boris Shingarov 32 */ 33 34/* 35 * Copyright (c) 1990, 1993 The Regents of the University of California 36 * All rights reserved 37 * 38 * This software was developed by the Computer Systems Engineering group 39 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 40 * contributed to Berkeley. 41 * 42 * All advertising materials mentioning features or use of this software 43 * must display the following acknowledgement: 44 * This product includes software developed by the University of 45 * California, Lawrence Berkeley Laboratories. 46 * 47 * Redistribution and use in source and binary forms, with or without 48 * modification, are permitted provided that the following conditions 49 * are met: 50 * 1. Redistributions of source code must retain the above copyright 51 * notice, this list of conditions and the following disclaimer. 52 * 2. Redistributions in binary form must reproduce the above copyright 53 * notice, this list of conditions and the following disclaimer in the 54 * documentation and/or other materials provided with the distribution. 55 * 3. All advertising materials mentioning features or use of this software 56 * must display the following acknowledgement: 57 * This product includes software developed by the University of 58 * California, Berkeley and its contributors. 59 * 4. Neither the name of the University nor the names of its contributors 60 * may be used to endorse or promote products derived from this software 61 * without specific prior written permission. 62 * 63 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 64 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 65 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 66 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 67 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 68 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 69 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 70 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 71 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 72 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 73 * SUCH DAMAGE. 74 * 75 * @(#)kgdb_stub.c 8.4 (Berkeley) 1/12/94 76 */ 77 78/*- 79 * Copyright (c) 2001 The NetBSD Foundation, Inc. 80 * All rights reserved. 81 * 82 * This code is derived from software contributed to The NetBSD Foundation 83 * by Jason R. Thorpe. 84 * 85 * Redistribution and use in source and binary forms, with or without 86 * modification, are permitted provided that the following conditions 87 * are met: 88 * 1. Redistributions of source code must retain the above copyright 89 * notice, this list of conditions and the following disclaimer. 90 * 2. Redistributions in binary form must reproduce the above copyright 91 * notice, this list of conditions and the following disclaimer in the 92 * documentation and/or other materials provided with the distribution. 93 * 3. All advertising materials mentioning features or use of this software 94 * must display the following acknowledgement: 95 * This product includes software developed by the NetBSD 96 * Foundation, Inc. and its contributors. 97 * 4. Neither the name of The NetBSD Foundation nor the names of its 98 * contributors may be used to endorse or promote products derived 99 * from this software without specific prior written permission. 100 * 101 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 102 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 103 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 104 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 105 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 106 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 107 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 108 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 109 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 110 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 111 * POSSIBILITY OF SUCH DAMAGE. 112 */ 113 114/* 115 * $NetBSD: kgdb_stub.c,v 1.8 2001/07/07 22:58:00 wdk Exp $ 116 * 117 * Taken from NetBSD 118 * 119 * "Stub" to allow remote cpu to debug over a serial line using gdb. 120 */ 121 122#include "base/remote_gdb.hh" 123 124#include <sys/signal.h> 125#include <unistd.h> 126 127#include <csignal> 128#include <cstdint> 129#include <cstdio> 130#include <string> 131 132#include "arch/vtophys.hh" 133#include "base/intmath.hh" 134#include "base/socket.hh" 135#include "base/trace.hh" 136#include "config/the_isa.hh" 137#include "cpu/base.hh" 138#include "cpu/static_inst.hh" 139#include "cpu/thread_context.hh" 140#include "debug/GDBAll.hh" 141#include "mem/fs_translating_port_proxy.hh" 142#include "mem/port.hh" 143#include "mem/se_translating_port_proxy.hh" 144#include "sim/full_system.hh" 145#include "sim/system.hh" 146 147using namespace std; 148using namespace TheISA; 149 150static const char GDBStart = '$'; 151static const char GDBEnd = '#'; 152static const char GDBGoodP = '+'; 153static const char GDBBadP = '-'; 154 155static const int GDBPacketBufLen = 1024; 156 157#ifndef NDEBUG 158vector<BaseRemoteGDB *> debuggers; 159 160void 161debugger() 162{ 163 static int current_debugger = -1; 164 if (current_debugger >= 0 && current_debugger < (int)debuggers.size()) { 165 BaseRemoteGDB *gdb = debuggers[current_debugger]; 166 if (!gdb->isattached()) 167 gdb->listener->accept(); 168 if (gdb->isattached()) 169 gdb->trap(SIGILL); 170 } 171} 172#endif 173 174/////////////////////////////////////////////////////////// 175// 176// 177// 178 179GDBListener::InputEvent::InputEvent(GDBListener *l, int fd, int e) 180 : PollEvent(fd, e), listener(l) 181{} 182 183void 184GDBListener::InputEvent::process(int revent) 185{ 186 listener->accept(); 187} 188 189GDBListener::GDBListener(BaseRemoteGDB *g, int p) 190 : inputEvent(NULL), gdb(g), port(p) 191{ 192 assert(!gdb->listener); 193 gdb->listener = this; 194} 195 196GDBListener::~GDBListener() 197{ 198 delete inputEvent; 199} 200 201string 202GDBListener::name() 203{ 204 return gdb->name() + ".listener"; 205} 206 207void 208GDBListener::listen() 209{ 210 if (ListenSocket::allDisabled()) { 211 warn_once("Sockets disabled, not accepting gdb connections"); 212 return; 213 } 214 215 while (!listener.listen(port, true)) { 216 DPRINTF(GDBMisc, "Can't bind port %d\n", port); 217 port++; 218 } 219 220 inputEvent = new InputEvent(this, listener.getfd(), POLLIN); 221 pollQueue.schedule(inputEvent); 222 223#ifndef NDEBUG 224 gdb->number = debuggers.size(); 225 debuggers.push_back(gdb); 226#endif 227 228#ifndef NDEBUG 229 ccprintf(cerr, "%d: %s: listening for remote gdb #%d on port %d\n", 230 curTick(), name(), gdb->number, port); 231#else 232 ccprintf(cerr, "%d: %s: listening for remote gdb on port %d\n", 233 curTick(), name(), port); 234#endif 235} 236 237void 238GDBListener::accept() 239{ 240 if (!listener.islistening()) 241 panic("GDBListener::accept(): cannot accept if we're not listening!"); 242 243 int sfd = listener.accept(true); 244 245 if (sfd != -1) { 246 if (gdb->isattached()) 247 close(sfd); 248 else 249 gdb->attach(sfd); 250 } 251} 252 253BaseRemoteGDB::InputEvent::InputEvent(BaseRemoteGDB *g, int fd, int e) 254 : PollEvent(fd, e), gdb(g) 255{} 256 257void 258BaseRemoteGDB::InputEvent::process(int revent) 259{ 260 if (gdb->trapEvent.scheduled()) { 261 warn("GDB trap event has already been scheduled! " 262 "Ignoring this input event."); 263 return; 264 } 265 266 if (revent & POLLIN) { 267 gdb->trapEvent.type(SIGILL); 268 gdb->scheduleInstCommitEvent(&gdb->trapEvent, 0); 269 } else if (revent & POLLNVAL) { 270 gdb->descheduleInstCommitEvent(&gdb->trapEvent); 271 gdb->detach(); 272 } 273} 274 275void 276BaseRemoteGDB::TrapEvent::process() 277{ 278 gdb->trap(_type); 279} 280 281void 282BaseRemoteGDB::SingleStepEvent::process() 283{ 284 if (!gdb->singleStepEvent.scheduled()) 285 gdb->scheduleInstCommitEvent(&gdb->singleStepEvent, 1); 286 gdb->trap(SIGTRAP); 287} 288 289BaseRemoteGDB::BaseRemoteGDB(System *_system, ThreadContext *c) : 290 inputEvent(NULL), trapEvent(this), listener(NULL), 291 number(-1), fd(-1), active(false), attached(false), system(_system), 292 context(c), singleStepEvent(this) 293{ 294} 295 296BaseRemoteGDB::~BaseRemoteGDB() 297{ 298 if (inputEvent) 299 delete inputEvent; 300} 301 302string 303BaseRemoteGDB::name() 304{ 305 return system->name() + ".remote_gdb"; 306} 307 308bool 309BaseRemoteGDB::isattached() 310{ return attached; } 311 312void 313BaseRemoteGDB::attach(int f) 314{ 315 fd = f; 316 317 inputEvent = new InputEvent(this, fd, POLLIN); 318 pollQueue.schedule(inputEvent); 319 320 attached = true; 321 DPRINTFN("remote gdb attached\n"); 322} 323 324void 325BaseRemoteGDB::detach() 326{ 327 attached = false; 328 active = false; 329 clearSingleStep(); 330 close(fd); 331 fd = -1; 332 333 pollQueue.remove(inputEvent); 334 DPRINTFN("remote gdb detached\n"); 335} 336 337///////////////////////// 338// 339// 340 341uint8_t 342BaseRemoteGDB::getbyte() 343{ 344 uint8_t b; 345 if (::read(fd, &b, sizeof(b)) == sizeof(b)) 346 return b; 347 348 throw BadClient("Couldn't read data from debugger."); 349} 350 351void 352BaseRemoteGDB::putbyte(uint8_t b) 353{ 354 if (::write(fd, &b, sizeof(b)) == sizeof(b)) 355 return; 356 357 throw BadClient("Couldn't write data to the debugger."); 358} 359 360// Send a packet to gdb 361void 362BaseRemoteGDB::send(const char *bp) 363{ 364 const char *p; 365 uint8_t csum, c; 366 367 DPRINTF(GDBSend, "send: %s\n", bp); 368 369 do { 370 p = bp; 371 // Start sending a packet 372 putbyte(GDBStart); 373 // Send the contents, and also keep a check sum. 374 for (csum = 0; (c = *p); p++) { 375 putbyte(c); 376 csum += c; 377 } 378 // Send the ending character. 379 putbyte(GDBEnd); 380 // Send the checksum. 381 putbyte(i2digit(csum >> 4)); 382 putbyte(i2digit(csum)); 383 // Try transmitting over and over again until the other end doesn't 384 // send an error back. 385 c = getbyte(); 386 } while ((c & 0x7f) == GDBBadP); 387} 388 389// Receive a packet from gdb 390int 391BaseRemoteGDB::recv(char *bp, int maxlen) 392{ 393 char *p; 394 uint8_t c; 395 int csum; 396 int len; 397 398 do { 399 p = bp; 400 csum = len = 0; 401 // Find the beginning of a packet 402 while ((c = getbyte()) != GDBStart); 403 404 // Read until you find the end of the data in the packet, and keep 405 // track of the check sum. 406 while (len < maxlen) { 407 c = getbyte(); 408 if (c == GDBEnd) 409 break; 410 c &= 0x7f; 411 csum += c; 412 *p++ = c; 413 len++; 414 } 415 416 // Mask the check sum, and terminate the command string. 417 csum &= 0xff; 418 *p = '\0'; 419 420 // If the command was too long, report an error. 421 if (len >= maxlen) { 422 putbyte(GDBBadP); 423 continue; 424 } 425 426 // Bring in the checksum. If the check sum matches, csum will be 0. 427 csum -= digit2i(getbyte()) * 16; 428 csum -= digit2i(getbyte()); 429 430 // If the check sum was correct 431 if (csum == 0) { 432 // Report that the packet was received correctly 433 putbyte(GDBGoodP); 434 // Sequence present? 435 if (bp[2] == ':') { 436 putbyte(bp[0]); 437 putbyte(bp[1]); 438 len -= 3; 439 memcpy(bp, bp+3, len); 440 } 441 break; 442 } 443 // Otherwise, report that there was a mistake. 444 putbyte(GDBBadP); 445 } while (1); 446 447 DPRINTF(GDBRecv, "recv: %s\n", bp); 448 449 return len; 450} 451 452// Read bytes from kernel address space for debugger. 453bool 454BaseRemoteGDB::read(Addr vaddr, size_t size, char *data) 455{ 456 static Addr lastaddr = 0; 457 static size_t lastsize = 0; 458 459 if (vaddr < 10) { 460 DPRINTF(GDBRead, "read: reading memory location zero!\n"); 461 vaddr = lastaddr + lastsize; 462 } 463 464 DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size); 465 466 if (FullSystem) { 467 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 468 proxy.readBlob(vaddr, (uint8_t*)data, size); 469 } else { 470 SETranslatingPortProxy &proxy = context->getMemProxy(); 471 proxy.readBlob(vaddr, (uint8_t*)data, size); 472 } 473 474#if TRACING_ON 475 if (DTRACE(GDBRead)) { 476 if (DTRACE(GDBExtra)) { 477 char buf[1024]; 478 mem2hex(buf, data, size); 479 DPRINTFNR(": %s\n", buf); 480 } else 481 DPRINTFNR("\n"); 482 } 483#endif 484 485 return true; 486} 487 488// Write bytes to kernel address space for debugger. 489bool 490BaseRemoteGDB::write(Addr vaddr, size_t size, const char *data) 491{ 492 static Addr lastaddr = 0; 493 static size_t lastsize = 0; 494 495 if (vaddr < 10) { 496 DPRINTF(GDBWrite, "write: writing memory location zero!\n"); 497 vaddr = lastaddr + lastsize; 498 } 499 500 if (DTRACE(GDBWrite)) { 501 DPRINTFN("write: addr=%#x, size=%d", vaddr, size); 502 if (DTRACE(GDBExtra)) { 503 char buf[1024]; 504 mem2hex(buf, data, size); 505 DPRINTFNR(": %s\n", buf); 506 } else 507 DPRINTFNR("\n"); 508 } 509 if (FullSystem) { 510 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 511 proxy.writeBlob(vaddr, (uint8_t*)data, size); 512 } else { 513 SETranslatingPortProxy &proxy = context->getMemProxy(); 514 proxy.writeBlob(vaddr, (uint8_t*)data, size); 515 } 516 517 return true; 518} 519 520void 521BaseRemoteGDB::clearSingleStep() 522{ 523 descheduleInstCommitEvent(&singleStepEvent); 524} 525 526void 527BaseRemoteGDB::setSingleStep() 528{ 529 if (!singleStepEvent.scheduled()) 530 scheduleInstCommitEvent(&singleStepEvent, 1); 531} 532 533PCEventQueue *BaseRemoteGDB::getPcEventQueue() 534{ 535 return &system->pcEventQueue; 536} 537 538EventQueue * 539BaseRemoteGDB::getComInstEventQueue() 540{ 541 BaseCPU *cpu = context->getCpuPtr(); 542 return cpu->comInstEventQueue[context->threadId()]; 543} 544 545void 546BaseRemoteGDB::scheduleInstCommitEvent(Event *ev, int delta) 547{ 548 EventQueue *eq = getComInstEventQueue(); 549 // Here "ticks" aren't simulator ticks which measure time, they're 550 // instructions committed by the CPU. 551 eq->schedule(ev, eq->getCurTick() + delta); 552} 553 554void 555BaseRemoteGDB::descheduleInstCommitEvent(Event *ev) 556{ 557 if (ev->scheduled()) 558 getComInstEventQueue()->deschedule(ev); 559} 560 561bool 562BaseRemoteGDB::checkBpLen(size_t len) 563{ 564 return len == sizeof(MachInst); 565} 566 567BaseRemoteGDB::HardBreakpoint::HardBreakpoint(BaseRemoteGDB *_gdb, Addr pc) 568 : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc), 569 gdb(_gdb), refcount(0) 570{ 571 DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc); 572} 573 574void 575BaseRemoteGDB::HardBreakpoint::process(ThreadContext *tc) 576{ 577 DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc()); 578 579 if (tc == gdb->context) 580 gdb->trap(SIGTRAP); 581} 582 583void 584BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len) 585{ 586 if (!checkBpLen(len)) 587 throw BadClient("Invalid breakpoint length\n"); 588 589 return insertHardBreak(addr, len); 590} 591 592void 593BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len) 594{ 595 if (!checkBpLen(len)) 596 throw BadClient("Invalid breakpoint length.\n"); 597 598 return removeHardBreak(addr, len); 599} 600 601void 602BaseRemoteGDB::insertHardBreak(Addr addr, size_t len) 603{ 604 if (!checkBpLen(len)) 605 throw BadClient("Invalid breakpoint length\n"); 606 607 DPRINTF(GDBMisc, "Inserting hardware breakpoint at %#x\n", addr); 608 609 HardBreakpoint *&bkpt = hardBreakMap[addr]; 610 if (bkpt == 0) 611 bkpt = new HardBreakpoint(this, addr); 612 613 bkpt->refcount++; 614} 615 616void 617BaseRemoteGDB::removeHardBreak(Addr addr, size_t len) 618{ 619 if (!checkBpLen(len)) 620 throw BadClient("Invalid breakpoint length\n"); 621 622 DPRINTF(GDBMisc, "Removing hardware breakpoint at %#x\n", addr); 623 624 break_iter_t i = hardBreakMap.find(addr); 625 if (i == hardBreakMap.end()) 626 throw CmdError("E0C"); 627 628 HardBreakpoint *hbp = (*i).second; 629 if (--hbp->refcount == 0) { 630 delete hbp; 631 hardBreakMap.erase(i); 632 } 633} 634 635void 636BaseRemoteGDB::setTempBreakpoint(Addr bkpt) 637{ 638 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 639 insertHardBreak(bkpt, sizeof(TheISA::MachInst)); 640} 641 642void 643BaseRemoteGDB::clearTempBreakpoint(Addr &bkpt) 644{ 645 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 646 removeHardBreak(bkpt, sizeof(TheISA::MachInst)); 647 bkpt = 0; 648} 649 650enum GdbBreakpointType { 651 GdbSoftBp = '0', 652 GdbHardBp = '1', 653 GdbWriteWp = '2', 654 GdbReadWp = '3', 655 GdbAccWp = '4', 656}; 657 658const char * 659BaseRemoteGDB::break_type(char c) 660{ 661 switch(c) { 662 case GdbSoftBp: return "software breakpoint"; 663 case GdbHardBp: return "hardware breakpoint"; 664 case GdbWriteWp: return "write watchpoint"; 665 case GdbReadWp: return "read watchpoint"; 666 case GdbAccWp: return "access watchpoint"; 667 default: return "unknown breakpoint/watchpoint"; 668 } 669} 670 671std::map<char, GdbCommand> BaseRemoteGDB::command_map = { 672 // last signal 673 { '?', { "KGDB_SIGNAL", &BaseRemoteGDB::cmd_signal } }, 674 // set baud (deprecated) 675 { 'b', { "KGDB_SET_BAUD", &BaseRemoteGDB::cmd_unsupported } }, 676 // set breakpoint (deprecated) 677 { 'B', { "KGDB_SET_BREAK", &BaseRemoteGDB::cmd_unsupported } }, 678 // resume 679 { 'c', { "KGDB_CONT", &BaseRemoteGDB::cmd_cont } }, 680 // continue with signal 681 { 'C', { "KGDB_ASYNC_CONT", &BaseRemoteGDB::cmd_async_cont } }, 682 // toggle debug flags (deprecated) 683 { 'd', { "KGDB_DEBUG", &BaseRemoteGDB::cmd_unsupported } }, 684 // detach remote gdb 685 { 'D', { "KGDB_DETACH", &BaseRemoteGDB::cmd_detach } }, 686 // read general registers 687 { 'g', { "KGDB_REG_R", &BaseRemoteGDB::cmd_reg_r } }, 688 // write general registers 689 { 'G', { "KGDB_REG_W", &BaseRemoteGDB::cmd_reg_w } }, 690 // set thread 691 { 'H', { "KGDB_SET_THREAD", &BaseRemoteGDB::cmd_set_thread } }, 692 // step a single cycle 693 { 'i', { "KGDB_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 694 // signal then cycle step 695 { 'I', { "KGDB_SIG_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 696 // kill program 697 { 'k', { "KGDB_KILL", &BaseRemoteGDB::cmd_detach } }, 698 // read memory 699 { 'm', { "KGDB_MEM_R", &BaseRemoteGDB::cmd_mem_r } }, 700 // write memory 701 { 'M', { "KGDB_MEM_W", &BaseRemoteGDB::cmd_mem_w } }, 702 // read register 703 { 'p', { "KGDB_READ_REG", &BaseRemoteGDB::cmd_unsupported } }, 704 // write register 705 { 'P', { "KGDB_SET_REG", &BaseRemoteGDB::cmd_unsupported } }, 706 // query variable 707 { 'q', { "KGDB_QUERY_VAR", &BaseRemoteGDB::cmd_query_var } }, 708 // set variable 709 { 'Q', { "KGDB_SET_VAR", &BaseRemoteGDB::cmd_unsupported } }, 710 // reset system (deprecated) 711 { 'r', { "KGDB_RESET", &BaseRemoteGDB::cmd_unsupported } }, 712 // step 713 { 's', { "KGDB_STEP", &BaseRemoteGDB::cmd_step } }, 714 // signal and step 715 { 'S', { "KGDB_ASYNC_STEP", &BaseRemoteGDB::cmd_async_step } }, 716 // find out if the thread is alive 717 { 'T', { "KGDB_THREAD_ALIVE", &BaseRemoteGDB::cmd_unsupported } }, 718 // target exited 719 { 'W', { "KGDB_TARGET_EXIT", &BaseRemoteGDB::cmd_unsupported } }, 720 // write memory 721 { 'X', { "KGDB_BINARY_DLOAD", &BaseRemoteGDB::cmd_unsupported } }, 722 // remove breakpoint or watchpoint 723 { 'z', { "KGDB_CLR_HW_BKPT", &BaseRemoteGDB::cmd_clr_hw_bkpt } }, 724 // insert breakpoint or watchpoint 725 { 'Z', { "KGDB_SET_HW_BKPT", &BaseRemoteGDB::cmd_set_hw_bkpt } }, 726}; 727 728 729bool 730BaseRemoteGDB::cmd_unsupported(GdbCommand::Context &ctx) 731{ 732 DPRINTF(GDBMisc, "Unsupported command: %s\n", ctx.cmd->name); 733 DDUMP(GDBMisc, ctx.data, ctx.len); 734 throw Unsupported(); 735} 736 737 738bool 739BaseRemoteGDB::cmd_signal(GdbCommand::Context &ctx) 740{ 741 send(csprintf("S%02x", ctx.type).c_str()); 742 return true; 743} 744 745bool 746BaseRemoteGDB::cmd_cont(GdbCommand::Context &ctx) 747{ 748 const char *p = ctx.data; 749 if (ctx.len) { 750 Addr newPc = hex2i(&p); 751 context->pcState(newPc); 752 } 753 clearSingleStep(); 754 return false; 755} 756 757bool 758BaseRemoteGDB::cmd_async_cont(GdbCommand::Context &ctx) 759{ 760 const char *p = ctx.data; 761 hex2i(&p); 762 if (*p++ == ';') { 763 Addr newPc = hex2i(&p); 764 context->pcState(newPc); 765 } 766 clearSingleStep(); 767 return false; 768} 769 770bool 771BaseRemoteGDB::cmd_detach(GdbCommand::Context &ctx) 772{ 773 detach(); 774 return false; 775} 776 777bool 778BaseRemoteGDB::cmd_reg_r(GdbCommand::Context &ctx) 779{ 780 char buf[2 * regCachePtr->size() + 1]; 781 buf[2 * regCachePtr->size()] = '\0'; 782 mem2hex(buf, regCachePtr->data(), regCachePtr->size()); 783 send(buf); 784 return true; 785} 786 787bool 788BaseRemoteGDB::cmd_reg_w(GdbCommand::Context &ctx) 789{ 790 const char *p = ctx.data; 791 p = hex2mem(regCachePtr->data(), p, regCachePtr->size()); 792 if (p == NULL || *p != '\0') 793 throw CmdError("E01"); 794 795 regCachePtr->setRegs(context); 796 send("OK"); 797 798 return true; 799} 800 801bool 802BaseRemoteGDB::cmd_set_thread(GdbCommand::Context &ctx) 803{ 804 const char *p = ctx.data + 1; // Ignore the subcommand byte. 805 if (hex2i(&p) != 0) 806 throw CmdError("E01"); 807 send("OK"); 808 return true; 809} 810 811bool 812BaseRemoteGDB::cmd_mem_r(GdbCommand::Context &ctx) 813{ 814 const char *p = ctx.data; 815 Addr addr = hex2i(&p); 816 if (*p++ != ',') 817 throw CmdError("E02"); 818 size_t len = hex2i(&p); 819 if (*p != '\0') 820 throw CmdError("E03"); 821 if (!acc(addr, len)) 822 throw CmdError("E05"); 823 824 char buf[len]; 825 if (!read(addr, len, buf)) 826 throw CmdError("E05"); 827 828 char temp[2 * len + 1]; 829 temp[2 * len] = '\0'; 830 mem2hex(temp, buf, len); 831 send(temp); 832 return true; 833} 834 835bool 836BaseRemoteGDB::cmd_mem_w(GdbCommand::Context &ctx) 837{ 838 const char *p = ctx.data; 839 Addr addr = hex2i(&p); 840 if (*p++ != ',') 841 throw CmdError("E06"); 842 size_t len = hex2i(&p); 843 if (*p++ != ':') 844 throw CmdError("E07"); 845 if (len * 2 > ctx.len - (p - ctx.data)) 846 throw CmdError("E08"); 847 char buf[len]; 848 p = (char *)hex2mem(buf, p, len); 849 if (p == NULL) 850 throw CmdError("E09"); 851 if (!acc(addr, len)) 852 throw CmdError("E0A"); 853 if (!write(addr, len, buf)) 854 throw CmdError("E0B"); 855 send("OK"); 856 return true; 857} 858 859bool 860BaseRemoteGDB::cmd_query_var(GdbCommand::Context &ctx) 861{ 862 if (string(ctx.data, ctx.len - 1) != "C") 863 throw Unsupported(); 864 send("QC0"); 865 return true; 866} 867 868bool 869BaseRemoteGDB::cmd_async_step(GdbCommand::Context &ctx) 870{ 871 const char *p = ctx.data; 872 hex2i(&p); // Ignore the subcommand byte. 873 if (*p++ == ';') { 874 Addr newPc = hex2i(&p); 875 context->pcState(newPc); 876 } 877 setSingleStep(); 878 return false; 879} 880 881bool 882BaseRemoteGDB::cmd_step(GdbCommand::Context &ctx) 883{ 884 if (ctx.len) { 885 const char *p = ctx.data; 886 Addr newPc = hex2i(&p); 887 context->pcState(newPc); 888 } 889 setSingleStep(); 890 return false; 891} 892 893bool 894BaseRemoteGDB::cmd_clr_hw_bkpt(GdbCommand::Context &ctx) 895{ 896 const char *p = ctx.data; 897 char subcmd = *p++; 898 if (*p++ != ',') 899 throw CmdError("E0D"); 900 Addr addr = hex2i(&p); 901 if (*p++ != ',') 902 throw CmdError("E0D"); 903 size_t len = hex2i(&p); 904 905 DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n", 906 break_type(subcmd), addr, len); 907 908 switch (subcmd) { 909 case GdbSoftBp: 910 removeSoftBreak(addr, len); 911 break; 912 case GdbHardBp: 913 removeHardBreak(addr, len); 914 break; 915 case GdbWriteWp: 916 case GdbReadWp: 917 case GdbAccWp: 918 default: // unknown 919 throw Unsupported(); 920 } 921 send("OK"); 922 923 return true; 924} 925 926bool 927BaseRemoteGDB::cmd_set_hw_bkpt(GdbCommand::Context &ctx) 928{ 929 const char *p = ctx.data; 930 char subcmd = *p++; 931 if (*p++ != ',') 932 throw CmdError("E0D"); 933 Addr addr = hex2i(&p); 934 if (*p++ != ',') 935 throw CmdError("E0D"); 936 size_t len = hex2i(&p); 937 938 DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n", 939 break_type(subcmd), addr, len); 940 941 switch (subcmd) { 942 case GdbSoftBp: 943 insertSoftBreak(addr, len); 944 break; 945 case GdbHardBp: 946 insertHardBreak(addr, len); 947 break; 948 case GdbWriteWp: 949 case GdbReadWp: 950 case GdbAccWp: 951 default: // unknown 952 throw Unsupported(); 953 } 954 send("OK"); 955 956 return true; 957} 958 959 960// This function does all command processing for interfacing to a 961// remote gdb. Note that the error codes are ignored by gdb at 962// present, but might eventually become meaningful. (XXX) It might 963// makes sense to use POSIX errno values, because that is what the 964// gdb/remote.c functions want to return. 965bool 966BaseRemoteGDB::trap(int type) 967{ 968 969 if (!attached) 970 return false; 971 972 DPRINTF(GDBMisc, "trap: PC=%s\n", context->pcState()); 973 974 clearSingleStep(); 975 976 /* 977 * The first entry to this function is normally through 978 * a breakpoint trap in kgdb_connect(), in which case we 979 * must advance past the breakpoint because gdb will not. 980 * 981 * On the first entry here, we expect that gdb is not yet 982 * listening to us, so just enter the interaction loop. 983 * After the debugger is "active" (connected) it will be 984 * waiting for a "signaled" message from us. 985 */ 986 if (!active) { 987 active = true; 988 } else { 989 // Tell remote host that an exception has occurred. 990 send(csprintf("S%02x", type).c_str()); 991 } 992 993 // Stick frame regs into our reg cache. 994 regCachePtr = gdbRegs(); 995 regCachePtr->getRegs(context); 996 997 char data[GDBPacketBufLen + 1]; 998 GdbCommand::Context cmdCtx; 999 cmdCtx.type = type; 1000 cmdCtx.data = &data[1]; 1001 1002 for (;;) { 1003 try { 1004 size_t datalen = recv(data, sizeof(data)); 1005 if (datalen < 1) 1006 throw BadClient(); 1007 1008 data[datalen] = 0; // Sentinel 1009 cmdCtx.cmd_byte = data[0]; 1010 cmdCtx.len = datalen - 1; 1011 1012 auto cmdIt = command_map.find(cmdCtx.cmd_byte); 1013 if (cmdIt == command_map.end()) { 1014 DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n", 1015 cmdCtx.cmd_byte, cmdCtx.cmd_byte); 1016 throw Unsupported(); 1017 } 1018 cmdCtx.cmd = &(cmdIt->second); 1019 1020 if (!(this->*(cmdCtx.cmd->func))(cmdCtx)) 1021 break; 1022 1023 } catch (BadClient &e) { 1024 if (e.warning) 1025 warn(e.warning); 1026 detach(); 1027 break; 1028 } catch (Unsupported &e) { 1029 send(""); 1030 } catch (CmdError &e) { 1031 send(e.error.c_str()); 1032 } catch (...) { 1033 panic("Unrecognzied GDB exception."); 1034 } 1035 } 1036 1037 return true; 1038} 1039 1040// Convert a hex digit into an integer. 1041// This returns -1 if the argument passed is no valid hex digit. 1042int 1043BaseRemoteGDB::digit2i(char c) 1044{ 1045 if (c >= '0' && c <= '9') 1046 return (c - '0'); 1047 else if (c >= 'a' && c <= 'f') 1048 return (c - 'a' + 10); 1049 else if (c >= 'A' && c <= 'F') 1050 return (c - 'A' + 10); 1051 else 1052 return (-1); 1053} 1054 1055// Convert the low 4 bits of an integer into an hex digit. 1056char 1057BaseRemoteGDB::i2digit(int n) 1058{ 1059 return ("0123456789abcdef"[n & 0x0f]); 1060} 1061 1062// Convert a byte array into an hex string. 1063void 1064BaseRemoteGDB::mem2hex(char *vdst, const char *vsrc, int len) 1065{ 1066 char *dst = vdst; 1067 const char *src = vsrc; 1068 1069 while (len--) { 1070 *dst++ = i2digit(*src >> 4); 1071 *dst++ = i2digit(*src++); 1072 } 1073 *dst = '\0'; 1074} 1075 1076// Convert an hex string into a byte array. 1077// This returns a pointer to the character following the last valid 1078// hex digit. If the string ends in the middle of a byte, NULL is 1079// returned. 1080const char * 1081BaseRemoteGDB::hex2mem(char *vdst, const char *src, int maxlen) 1082{ 1083 char *dst = vdst; 1084 int msb, lsb; 1085 1086 while (*src && maxlen--) { 1087 msb = digit2i(*src++); 1088 if (msb < 0) 1089 return (src - 1); 1090 lsb = digit2i(*src++); 1091 if (lsb < 0) 1092 return (NULL); 1093 *dst++ = (msb << 4) | lsb; 1094 } 1095 return src; 1096} 1097 1098// Convert an hex string into an integer. 1099// This returns a pointer to the character following the last valid 1100// hex digit. 1101Addr 1102BaseRemoteGDB::hex2i(const char **srcp) 1103{ 1104 const char *src = *srcp; 1105 Addr r = 0; 1106 int nibble; 1107 1108 while ((nibble = digit2i(*src)) >= 0) { 1109 r *= 16; 1110 r += nibble; 1111 src++; 1112 } 1113 *srcp = src; 1114 return r; 1115} 1116 1117