Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/i386/i386/db_trace.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /* 2 * Mach Operating System 3 * Copyright (c) 1991,1990 Carnegie Mellon University 4 * All Rights Reserved. 5 * 6 * Permission to use, copy, modify and distribute this software and its 7 * documentation is hereby granted, provided that both the copyright 8 * notice and this permission notice appear in all copies of the 9 * software, derivative works or modified versions, and any portions 10 * thereof, and that both notices appear in supporting documentation. 11 * 12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS 13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 15 * 16 * Carnegie Mellon requests users of this software to return to 17 * 18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 19 * School of Computer Science 20 * Carnegie Mellon University 21 * Pittsburgh PA 15213-3890 22 * 23 * any improvements or extensions that they make and grant Carnegie the 24 * rights to redistribute these changes. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD: releng/5.3/sys/i386/i386/db_trace.c 135309 2004-09-16 17:21:46Z jhb $"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/kdb.h> 33 #include <sys/proc.h> 34 #include <sys/sysent.h> 35 36 #include <machine/cpu.h> 37 #include <machine/md_var.h> 38 #include <machine/pcb.h> 39 #include <machine/reg.h> 40 41 #include <vm/vm.h> 42 #include <vm/vm_param.h> 43 #include <vm/pmap.h> 44 45 #include <ddb/ddb.h> 46 #include <ddb/db_access.h> 47 #include <ddb/db_sym.h> 48 #include <ddb/db_variables.h> 49 50 static db_varfcn_t db_dr0; 51 static db_varfcn_t db_dr1; 52 static db_varfcn_t db_dr2; 53 static db_varfcn_t db_dr3; 54 static db_varfcn_t db_dr4; 55 static db_varfcn_t db_dr5; 56 static db_varfcn_t db_dr6; 57 static db_varfcn_t db_dr7; 58 static db_varfcn_t db_esp; 59 static db_varfcn_t db_frame; 60 static db_varfcn_t db_ss; 61 62 /* 63 * Machine register set. 64 */ 65 #define DB_OFFSET(x) (db_expr_t *)offsetof(struct trapframe, x) 66 struct db_variable db_regs[] = { 67 { "cs", DB_OFFSET(tf_cs), db_frame }, 68 { "ds", DB_OFFSET(tf_ds), db_frame }, 69 { "es", DB_OFFSET(tf_es), db_frame }, 70 { "fs", DB_OFFSET(tf_fs), db_frame }, 71 { "ss", NULL, db_ss }, 72 { "eax", DB_OFFSET(tf_eax), db_frame }, 73 { "ecx", DB_OFFSET(tf_ecx), db_frame }, 74 { "edx", DB_OFFSET(tf_edx), db_frame }, 75 { "ebx", DB_OFFSET(tf_ebx), db_frame }, 76 { "esp", NULL, db_esp }, 77 { "ebp", DB_OFFSET(tf_ebp), db_frame }, 78 { "esi", DB_OFFSET(tf_esi), db_frame }, 79 { "edi", DB_OFFSET(tf_edi), db_frame }, 80 { "eip", DB_OFFSET(tf_eip), db_frame }, 81 { "efl", DB_OFFSET(tf_eflags), db_frame }, 82 { "dr0", NULL, db_dr0 }, 83 { "dr1", NULL, db_dr1 }, 84 { "dr2", NULL, db_dr2 }, 85 { "dr3", NULL, db_dr3 }, 86 { "dr4", NULL, db_dr4 }, 87 { "dr5", NULL, db_dr5 }, 88 { "dr6", NULL, db_dr6 }, 89 { "dr7", NULL, db_dr7 }, 90 }; 91 struct db_variable *db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]); 92 93 #define DB_DRX_FUNC(reg) \ 94 static int \ 95 db_ ## reg (vp, valuep, op) \ 96 struct db_variable *vp; \ 97 db_expr_t * valuep; \ 98 int op; \ 99 { \ 100 if (op == DB_VAR_GET) \ 101 *valuep = r ## reg (); \ 102 else \ 103 load_ ## reg (*valuep); \ 104 return (1); \ 105 } 106 107 DB_DRX_FUNC(dr0) 108 DB_DRX_FUNC(dr1) 109 DB_DRX_FUNC(dr2) 110 DB_DRX_FUNC(dr3) 111 DB_DRX_FUNC(dr4) 112 DB_DRX_FUNC(dr5) 113 DB_DRX_FUNC(dr6) 114 DB_DRX_FUNC(dr7) 115 116 static __inline int 117 get_esp(struct trapframe *tf) 118 { 119 return ((ISPL(tf->tf_cs)) ? tf->tf_esp : 120 (db_expr_t)tf + (uintptr_t)DB_OFFSET(tf_esp)); 121 } 122 123 static int 124 db_frame(struct db_variable *vp, db_expr_t *valuep, int op) 125 { 126 int *reg; 127 128 if (kdb_frame == NULL) 129 return (0); 130 131 reg = (int *)((uintptr_t)kdb_frame + (db_expr_t)vp->valuep); 132 if (op == DB_VAR_GET) 133 *valuep = *reg; 134 else 135 *reg = *valuep; 136 return (1); 137 } 138 139 static int 140 db_esp(struct db_variable *vp, db_expr_t *valuep, int op) 141 { 142 143 if (kdb_frame == NULL) 144 return (0); 145 146 if (op == DB_VAR_GET) 147 *valuep = get_esp(kdb_frame); 148 else if (ISPL(kdb_frame->tf_cs)) 149 kdb_frame->tf_esp = *valuep; 150 return (1); 151 } 152 153 static int 154 db_ss(struct db_variable *vp, db_expr_t *valuep, int op) 155 { 156 157 if (kdb_frame == NULL) 158 return (0); 159 160 if (op == DB_VAR_GET) 161 *valuep = (ISPL(kdb_frame->tf_cs)) ? kdb_frame->tf_ss : rss(); 162 else if (ISPL(kdb_frame->tf_cs)) 163 kdb_frame->tf_ss = *valuep; 164 return (1); 165 } 166 167 /* 168 * Stack trace. 169 */ 170 #define INKERNEL(va) (((vm_offset_t)(va)) >= USRSTACK) 171 172 struct i386_frame { 173 struct i386_frame *f_frame; 174 int f_retaddr; 175 int f_arg0; 176 }; 177 178 #define NORMAL 0 179 #define TRAP 1 180 #define INTERRUPT 2 181 #define SYSCALL 3 182 #define DOUBLE_FAULT 4 183 184 static void db_nextframe(struct i386_frame **, db_addr_t *, struct thread *); 185 static int db_numargs(struct i386_frame *); 186 static void db_print_stack_entry(const char *, int, char **, int *, db_addr_t); 187 static void decode_syscall(int, struct thread *); 188 189 static char * watchtype_str(int type); 190 int i386_set_watch(int watchnum, unsigned int watchaddr, int size, int access, 191 struct dbreg * d); 192 int i386_clr_watch(int watchnum, struct dbreg * d); 193 int db_md_set_watchpoint(db_expr_t addr, db_expr_t size); 194 int db_md_clr_watchpoint(db_expr_t addr, db_expr_t size); 195 void db_md_list_watchpoints(void); 196 197 /* 198 * Figure out how many arguments were passed into the frame at "fp". 199 */ 200 static int 201 db_numargs(fp) 202 struct i386_frame *fp; 203 { 204 int *argp; 205 int inst; 206 int args; 207 208 argp = (int *)db_get_value((int)&fp->f_retaddr, 4, FALSE); 209 /* 210 * XXX etext is wrong for LKMs. We should attempt to interpret 211 * the instruction at the return address in all cases. This 212 * may require better fault handling. 213 */ 214 if (argp < (int *)btext || argp >= (int *)etext) { 215 args = 5; 216 } else { 217 inst = db_get_value((int)argp, 4, FALSE); 218 if ((inst & 0xff) == 0x59) /* popl %ecx */ 219 args = 1; 220 else if ((inst & 0xffff) == 0xc483) /* addl $Ibs, %esp */ 221 args = ((inst >> 16) & 0xff) / 4; 222 else 223 args = 5; 224 } 225 return (args); 226 } 227 228 static void 229 db_print_stack_entry(name, narg, argnp, argp, callpc) 230 const char *name; 231 int narg; 232 char **argnp; 233 int *argp; 234 db_addr_t callpc; 235 { 236 db_printf("%s(", name); 237 while (narg) { 238 if (argnp) 239 db_printf("%s=", *argnp++); 240 db_printf("%r", db_get_value((int)argp, 4, FALSE)); 241 argp++; 242 if (--narg != 0) 243 db_printf(","); 244 } 245 db_printf(") at "); 246 db_printsym(callpc, DB_STGY_PROC); 247 db_printf("\n"); 248 } 249 250 static void 251 decode_syscall(int number, struct thread *td) 252 { 253 struct proc *p; 254 c_db_sym_t sym; 255 db_expr_t diff; 256 sy_call_t *f; 257 const char *symname; 258 259 db_printf(" (%d", number); 260 p = (td != NULL) ? td->td_proc : NULL; 261 if (p != NULL && 0 <= number && number < p->p_sysent->sv_size) { 262 f = p->p_sysent->sv_table[number].sy_call; 263 sym = db_search_symbol((db_addr_t)f, DB_STGY_ANY, &diff); 264 if (sym != DB_SYM_NULL && diff == 0) { 265 db_symbol_values(sym, &symname, NULL); 266 db_printf(", %s, %s", p->p_sysent->sv_name, symname); 267 } 268 } 269 db_printf(")"); 270 } 271 272 /* 273 * Figure out the next frame up in the call stack. 274 */ 275 static void 276 db_nextframe(struct i386_frame **fp, db_addr_t *ip, struct thread *td) 277 { 278 struct trapframe *tf; 279 int frame_type; 280 int eip, esp, ebp; 281 db_expr_t offset; 282 c_db_sym_t sym; 283 const char *name; 284 285 eip = db_get_value((int) &(*fp)->f_retaddr, 4, FALSE); 286 ebp = db_get_value((int) &(*fp)->f_frame, 4, FALSE); 287 288 /* 289 * Figure out frame type. 290 */ 291 frame_type = NORMAL; 292 sym = db_search_symbol(eip, DB_STGY_ANY, &offset); 293 db_symbol_values(sym, &name, NULL); 294 if (name != NULL) { 295 if (strcmp(name, "calltrap") == 0 || 296 strcmp(name, "fork_trampoline") == 0) 297 frame_type = TRAP; 298 else if (strncmp(name, "Xatpic_intr", 11) == 0 || 299 strncmp(name, "Xapic_isr", 9) == 0) 300 frame_type = INTERRUPT; 301 else if (strcmp(name, "Xlcall_syscall") == 0 || 302 strcmp(name, "Xint0x80_syscall") == 0) 303 frame_type = SYSCALL; 304 else if (strcmp(name, "dblfault_handler") == 0) 305 frame_type = DOUBLE_FAULT; 306 } 307 308 /* 309 * Normal frames need no special processing. 310 */ 311 if (frame_type == NORMAL) { 312 *ip = (db_addr_t) eip; 313 *fp = (struct i386_frame *) ebp; 314 return; 315 } 316 317 db_print_stack_entry(name, 0, 0, 0, eip); 318 319 /* 320 * For a double fault, we have to snag the values from the 321 * previous TSS since a double fault uses a task gate to 322 * switch to a known good state. 323 */ 324 if (frame_type == DOUBLE_FAULT) { 325 esp = PCPU_GET(common_tss.tss_esp); 326 eip = PCPU_GET(common_tss.tss_eip); 327 ebp = PCPU_GET(common_tss.tss_ebp); 328 db_printf( 329 "--- trap 0x17, eip = %#r, esp = %#r, ebp = %#r ---\n", 330 eip, esp, ebp); 331 *ip = (db_addr_t) eip; 332 *fp = (struct i386_frame *) ebp; 333 return; 334 } 335 336 /* 337 * Point to base of trapframe which is just above the 338 * current frame. 339 */ 340 if (frame_type == INTERRUPT) 341 tf = (struct trapframe *)((int)*fp + 12); 342 else 343 tf = (struct trapframe *)((int)*fp + 8); 344 345 if (INKERNEL((int) tf)) { 346 esp = get_esp(tf); 347 eip = tf->tf_eip; 348 ebp = tf->tf_ebp; 349 switch (frame_type) { 350 case TRAP: 351 db_printf("--- trap %#r", tf->tf_trapno); 352 break; 353 case SYSCALL: 354 db_printf("--- syscall"); 355 decode_syscall(tf->tf_eax, td); 356 break; 357 case INTERRUPT: 358 db_printf("--- interrupt"); 359 break; 360 default: 361 panic("The moon has moved again."); 362 } 363 db_printf(", eip = %#r, esp = %#r, ebp = %#r ---\n", eip, 364 esp, ebp); 365 } 366 367 *ip = (db_addr_t) eip; 368 *fp = (struct i386_frame *) ebp; 369 } 370 371 static int 372 db_backtrace(struct thread *td, struct trapframe *tf, struct i386_frame *frame, 373 db_addr_t pc, int count) 374 { 375 struct i386_frame *actframe; 376 #define MAXNARG 16 377 char *argnames[MAXNARG], **argnp = NULL; 378 const char *name; 379 int *argp; 380 db_expr_t offset; 381 c_db_sym_t sym; 382 int narg; 383 boolean_t first; 384 385 if (count == -1) 386 count = 1024; 387 388 first = TRUE; 389 while (count--) { 390 sym = db_search_symbol(pc, DB_STGY_ANY, &offset); 391 db_symbol_values(sym, &name, NULL); 392 393 /* 394 * Attempt to determine a (possibly fake) frame that gives 395 * the caller's pc. It may differ from `frame' if the 396 * current function never sets up a standard frame or hasn't 397 * set one up yet or has just discarded one. The last two 398 * cases can be guessed fairly reliably for code generated 399 * by gcc. The first case is too much trouble to handle in 400 * general because the amount of junk on the stack depends 401 * on the pc (the special handling of "calltrap", etc. in 402 * db_nextframe() works because the `next' pc is special). 403 */ 404 actframe = frame; 405 if (first) { 406 if (tf != NULL) { 407 int instr; 408 409 instr = db_get_value(pc, 4, FALSE); 410 if ((instr & 0xffffff) == 0x00e58955) { 411 /* pushl %ebp; movl %esp, %ebp */ 412 actframe = (void *)(get_esp(tf) - 4); 413 } else if ((instr & 0xffff) == 0x0000e589) { 414 /* movl %esp, %ebp */ 415 actframe = (void *)get_esp(tf); 416 if (tf->tf_ebp == 0) { 417 /* Fake frame better. */ 418 frame = actframe; 419 } 420 } else if ((instr & 0xff) == 0x000000c3) { 421 /* ret */ 422 actframe = (void *)(get_esp(tf) - 4); 423 } else if (offset == 0) { 424 /* Probably an assembler symbol. */ 425 actframe = (void *)(get_esp(tf) - 4); 426 } 427 } else if (strcmp(name, "fork_trampoline") == 0) { 428 /* 429 * Don't try to walk back on a stack for a 430 * process that hasn't actually been run yet. 431 */ 432 db_print_stack_entry(name, 0, 0, 0, pc); 433 break; 434 } 435 first = FALSE; 436 } 437 438 argp = &actframe->f_arg0; 439 narg = MAXNARG; 440 if (sym != NULL && db_sym_numargs(sym, &narg, argnames)) { 441 argnp = argnames; 442 } else { 443 narg = db_numargs(frame); 444 } 445 446 db_print_stack_entry(name, narg, argnp, argp, pc); 447 448 if (actframe != frame) { 449 /* `frame' belongs to caller. */ 450 pc = (db_addr_t) 451 db_get_value((int)&actframe->f_retaddr, 4, FALSE); 452 continue; 453 } 454 455 db_nextframe(&frame, &pc, td); 456 457 if (INKERNEL((int)pc) && !INKERNEL((int) frame)) { 458 sym = db_search_symbol(pc, DB_STGY_ANY, &offset); 459 db_symbol_values(sym, &name, NULL); 460 db_print_stack_entry(name, 0, 0, 0, pc); 461 break; 462 } 463 if (!INKERNEL((int) frame)) { 464 break; 465 } 466 } 467 468 return (0); 469 } 470 471 void 472 db_trace_self(void) 473 { 474 struct i386_frame *frame; 475 db_addr_t callpc; 476 register_t ebp; 477 478 __asm __volatile("movl %%ebp,%0" : "=r" (ebp)); 479 frame = (struct i386_frame *)ebp; 480 callpc = (db_addr_t)db_get_value((int)&frame->f_retaddr, 4, FALSE); 481 frame = frame->f_frame; 482 db_backtrace(curthread, NULL, frame, callpc, -1); 483 } 484 485 int 486 db_trace_thread(struct thread *thr, int count) 487 { 488 struct pcb *ctx; 489 490 ctx = kdb_thr_ctx(thr); 491 return (db_backtrace(thr, NULL, (struct i386_frame *)ctx->pcb_ebp, 492 ctx->pcb_eip, count)); 493 } 494 495 int 496 i386_set_watch(watchnum, watchaddr, size, access, d) 497 int watchnum; 498 unsigned int watchaddr; 499 int size; 500 int access; 501 struct dbreg * d; 502 { 503 int i; 504 unsigned int mask; 505 506 if (watchnum == -1) { 507 for (i = 0, mask = 0x3; i < 4; i++, mask <<= 2) 508 if ((d->dr[7] & mask) == 0) 509 break; 510 if (i < 4) 511 watchnum = i; 512 else 513 return (-1); 514 } 515 516 switch (access) { 517 case DBREG_DR7_EXEC: 518 size = 1; /* size must be 1 for an execution breakpoint */ 519 /* fall through */ 520 case DBREG_DR7_WRONLY: 521 case DBREG_DR7_RDWR: 522 break; 523 default : return (-1); 524 } 525 526 /* 527 * we can watch a 1, 2, or 4 byte sized location 528 */ 529 switch (size) { 530 case 1 : mask = 0x00; break; 531 case 2 : mask = 0x01 << 2; break; 532 case 4 : mask = 0x03 << 2; break; 533 default : return (-1); 534 } 535 536 mask |= access; 537 538 /* clear the bits we are about to affect */ 539 d->dr[7] &= ~((0x3 << (watchnum*2)) | (0x0f << (watchnum*4+16))); 540 541 /* set drN register to the address, N=watchnum */ 542 DBREG_DRX(d,watchnum) = watchaddr; 543 544 /* enable the watchpoint */ 545 d->dr[7] |= (0x2 << (watchnum*2)) | (mask << (watchnum*4+16)); 546 547 return (watchnum); 548 } 549 550 551 int 552 i386_clr_watch(watchnum, d) 553 int watchnum; 554 struct dbreg * d; 555 { 556 557 if (watchnum < 0 || watchnum >= 4) 558 return (-1); 559 560 d->dr[7] = d->dr[7] & ~((0x3 << (watchnum*2)) | (0x0f << (watchnum*4+16))); 561 DBREG_DRX(d,watchnum) = 0; 562 563 return (0); 564 } 565 566 567 int 568 db_md_set_watchpoint(addr, size) 569 db_expr_t addr; 570 db_expr_t size; 571 { 572 int avail, wsize; 573 int i; 574 struct dbreg d; 575 576 fill_dbregs(NULL, &d); 577 578 avail = 0; 579 for(i=0; i<4; i++) { 580 if ((d.dr[7] & (3 << (i*2))) == 0) 581 avail++; 582 } 583 584 if (avail*4 < size) 585 return (-1); 586 587 for (i=0; i<4 && (size != 0); i++) { 588 if ((d.dr[7] & (3<<(i*2))) == 0) { 589 if (size > 4) 590 wsize = 4; 591 else 592 wsize = size; 593 if (wsize == 3) 594 wsize++; 595 i386_set_watch(i, addr, wsize, 596 DBREG_DR7_WRONLY, &d); 597 addr += wsize; 598 size -= wsize; 599 } 600 } 601 602 set_dbregs(NULL, &d); 603 604 return(0); 605 } 606 607 608 int 609 db_md_clr_watchpoint(addr, size) 610 db_expr_t addr; 611 db_expr_t size; 612 { 613 int i; 614 struct dbreg d; 615 616 fill_dbregs(NULL, &d); 617 618 for(i=0; i<4; i++) { 619 if (d.dr[7] & (3 << (i*2))) { 620 if ((DBREG_DRX((&d), i) >= addr) && 621 (DBREG_DRX((&d), i) < addr+size)) 622 i386_clr_watch(i, &d); 623 624 } 625 } 626 627 set_dbregs(NULL, &d); 628 629 return(0); 630 } 631 632 633 static 634 char * 635 watchtype_str(type) 636 int type; 637 { 638 switch (type) { 639 case DBREG_DR7_EXEC : return "execute"; break; 640 case DBREG_DR7_RDWR : return "read/write"; break; 641 case DBREG_DR7_WRONLY : return "write"; break; 642 default : return "invalid"; break; 643 } 644 } 645 646 647 void 648 db_md_list_watchpoints() 649 { 650 int i; 651 struct dbreg d; 652 653 fill_dbregs(NULL, &d); 654 655 db_printf("\nhardware watchpoints:\n"); 656 db_printf(" watch status type len address\n"); 657 db_printf(" ----- -------- ---------- --- ----------\n"); 658 for (i=0; i<4; i++) { 659 if (d.dr[7] & (0x03 << (i*2))) { 660 unsigned type, len; 661 type = (d.dr[7] >> (16+(i*4))) & 3; 662 len = (d.dr[7] >> (16+(i*4)+2)) & 3; 663 db_printf(" %-5d %-8s %10s %3d 0x%08x\n", 664 i, "enabled", watchtype_str(type), 665 len+1, DBREG_DRX((&d),i)); 666 } 667 else { 668 db_printf(" %-5d disabled\n", i); 669 } 670 } 671 672 db_printf("\ndebug register values:\n"); 673 for (i=0; i<8; i++) { 674 db_printf(" dr%d 0x%08x\n", i, DBREG_DRX((&d),i)); 675 } 676 db_printf("\n"); 677 } 678 679
Cache object: e67ef1552c8756558b02601d160e3ab6
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]