sys/i386/i386/db_trace.c

   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("$FreeBSD$");
  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 #include <machine/stack.h>
  41
  42 #include <vm/vm.h>
  43 #include <vm/vm_param.h>
  44 #include <vm/pmap.h>
  45
  46 #include <ddb/ddb.h>
  47 #include <ddb/db_access.h>
  48 #include <ddb/db_sym.h>
  49 #include <ddb/db_variables.h>
  50
  51 static db_varfcn_t db_esp;
  52 static db_varfcn_t db_frame;
  53 static db_varfcn_t db_frame_seg;
  54 static db_varfcn_t db_gs;
  55 static db_varfcn_t db_ss;
  56
  57 /*
  58  * Machine register set.
  59  */
  60 #define DB_OFFSET(x)    (db_expr_t *)offsetof(struct trapframe, x)
  61 struct db_variable db_regs[] = {
  62         { "cs",         DB_OFFSET(tf_cs),       db_frame_seg },
  63         { "ds",         DB_OFFSET(tf_ds),       db_frame_seg },
  64         { "es",         DB_OFFSET(tf_es),       db_frame_seg },
  65         { "fs",         DB_OFFSET(tf_fs),       db_frame_seg },
  66         { "gs",         NULL,                   db_gs },
  67         { "ss",         NULL,                   db_ss },
  68         { "eax",        DB_OFFSET(tf_eax),      db_frame },
  69         { "ecx",        DB_OFFSET(tf_ecx),      db_frame },
  70         { "edx",        DB_OFFSET(tf_edx),      db_frame },
  71         { "ebx",        DB_OFFSET(tf_ebx),      db_frame },
  72         { "esp",        NULL,                   db_esp },
  73         { "ebp",        DB_OFFSET(tf_ebp),      db_frame },
  74         { "esi",        DB_OFFSET(tf_esi),      db_frame },
  75         { "edi",        DB_OFFSET(tf_edi),      db_frame },
  76         { "eip",        DB_OFFSET(tf_eip),      db_frame },
  77         { "efl",        DB_OFFSET(tf_eflags),   db_frame },
  78 };
  79 struct db_variable *db_eregs = db_regs + nitems(db_regs);
  80
  81 static __inline int
  82 get_esp(struct trapframe *tf)
  83 {
  84         return ((ISPL(tf->tf_cs)) ? tf->tf_esp :
  85             (db_expr_t)tf + (uintptr_t)DB_OFFSET(tf_esp));
  86 }
  87
  88 static int
  89 db_frame(struct db_variable *vp, db_expr_t *valuep, int op)
  90 {
  91         int *reg;
  92
  93         if (kdb_frame == NULL)
  94                 return (0);
  95
  96         reg = (int *)((uintptr_t)kdb_frame + (db_expr_t)vp->valuep);
  97         if (op == DB_VAR_GET)
  98                 *valuep = *reg;
  99         else
 100                 *reg = *valuep;
 101         return (1);
 102 }
 103
 104 static int
 105 db_frame_seg(struct db_variable *vp, db_expr_t *valuep, int op)
 106 {
 107         uint16_t *reg;
 108
 109         if (kdb_frame == NULL)
 110                 return (0);
 111
 112         reg = (uint16_t *)((uintptr_t)kdb_frame + (db_expr_t)vp->valuep);
 113         if (op == DB_VAR_GET)
 114                 *valuep = *reg;
 115         else
 116                 *reg = *valuep;
 117         return (1);
 118 }
 119
 120 static int
 121 db_esp(struct db_variable *vp, db_expr_t *valuep, int op)
 122 {
 123
 124         if (kdb_frame == NULL)
 125                 return (0);
 126
 127         if (op == DB_VAR_GET)
 128                 *valuep = get_esp(kdb_frame);
 129         else if (ISPL(kdb_frame->tf_cs))
 130                 kdb_frame->tf_esp = *valuep;
 131         return (1);
 132 }
 133
 134 static int
 135 db_gs(struct db_variable *vp, db_expr_t *valuep, int op)
 136 {
 137
 138         if (op == DB_VAR_GET)
 139                 *valuep = rgs();
 140         else
 141                 load_gs(*valuep);
 142         return (1);
 143 }
 144
 145 static int
 146 db_ss(struct db_variable *vp, db_expr_t *valuep, int op)
 147 {
 148
 149         if (kdb_frame == NULL)
 150                 return (0);
 151
 152         if (op == DB_VAR_GET)
 153                 *valuep = (ISPL(kdb_frame->tf_cs)) ? kdb_frame->tf_ss : rss();
 154         else if (ISPL(kdb_frame->tf_cs))
 155                 kdb_frame->tf_ss = *valuep;
 156         return (1);
 157 }
 158
 159 #define NORMAL          0
 160 #define TRAP            1
 161 #define INTERRUPT       2
 162 #define SYSCALL         3
 163 #define DOUBLE_FAULT    4
 164 #define TRAP_INTERRUPT  5
 165 #define TRAP_TIMERINT   6
 166
 167 static void db_nextframe(struct i386_frame **, db_addr_t *, struct thread *);
 168 static int db_numargs(struct i386_frame *);
 169 static void db_print_stack_entry(const char *, int, char **, int *, db_addr_t,
 170     void *);
 171 static void decode_syscall(int, struct thread *);
 172
 173 static const char * watchtype_str(int type);
 174 int  i386_set_watch(int watchnum, unsigned int watchaddr, int size, int access,
 175                     struct dbreg *d);
 176 int  i386_clr_watch(int watchnum, struct dbreg *d);
 177
 178 /*
 179  * Figure out how many arguments were passed into the frame at "fp".
 180  */
 181 static int
 182 db_numargs(fp)
 183         struct i386_frame *fp;
 184 {
 185         char   *argp;
 186         int     inst;
 187         int     args;
 188
 189         argp = (char *)db_get_value((int)&fp->f_retaddr, 4, FALSE);
 190         /*
 191          * XXX etext is wrong for LKMs.  We should attempt to interpret
 192          * the instruction at the return address in all cases.  This
 193          * may require better fault handling.
 194          */
 195         if (argp < btext || argp >= etext) {
 196                 args = -1;
 197         } else {
 198 retry:
 199                 inst = db_get_value((int)argp, 4, FALSE);
 200                 if ((inst & 0xff) == 0x59)      /* popl %ecx */
 201                         args = 1;
 202                 else if ((inst & 0xffff) == 0xc483)     /* addl $Ibs, %esp */
 203                         args = ((inst >> 16) & 0xff) / 4;
 204                 else if ((inst & 0xf8ff) == 0xc089) {   /* movl %eax, %Reg */
 205                         argp += 2;
 206                         goto retry;
 207                 } else
 208                         args = -1;
 209         }
 210         return (args);
 211 }
 212
 213 static void
 214 db_print_stack_entry(name, narg, argnp, argp, callpc, frame)
 215         const char *name;
 216         int narg;
 217         char **argnp;
 218         int *argp;
 219         db_addr_t callpc;
 220         void *frame;
 221 {
 222         int n = narg >= 0 ? narg : 5;
 223
 224         db_printf("%s(", name);
 225         while (n) {
 226                 if (argnp)
 227                         db_printf("%s=", *argnp++);
 228                 db_printf("%r", db_get_value((int)argp, 4, FALSE));
 229                 argp++;
 230                 if (--n != 0)
 231                         db_printf(",");
 232         }
 233         if (narg < 0)
 234                 db_printf(",...");
 235         db_printf(") at ");
 236         db_printsym(callpc, DB_STGY_PROC);
 237         if (frame != NULL)
 238                 db_printf("/frame 0x%r", (register_t)frame);
 239         db_printf("\n");
 240 }
 241
 242 static void
 243 decode_syscall(int number, struct thread *td)
 244 {
 245         struct proc *p;
 246         c_db_sym_t sym;
 247         db_expr_t diff;
 248         sy_call_t *f;
 249         const char *symname;
 250
 251         db_printf(" (%d", number);
 252         p = (td != NULL) ? td->td_proc : NULL;
 253         if (p != NULL && 0 <= number && number < p->p_sysent->sv_size) {
 254                 f = p->p_sysent->sv_table[number].sy_call;
 255                 sym = db_search_symbol((db_addr_t)f, DB_STGY_ANY, &diff);
 256                 if (sym != DB_SYM_NULL && diff == 0) {
 257                         db_symbol_values(sym, &symname, NULL);
 258                         db_printf(", %s, %s", p->p_sysent->sv_name, symname);
 259                 }
 260         }
 261         db_printf(")");
 262 }
 263
 264 /*
 265  * Figure out the next frame up in the call stack.
 266  */
 267 static void
 268 db_nextframe(struct i386_frame **fp, db_addr_t *ip, struct thread *td)
 269 {
 270         struct trapframe *tf;
 271         int frame_type;
 272         int eip, esp, ebp;
 273         db_expr_t offset;
 274         c_db_sym_t sym;
 275         const char *name;
 276
 277         eip = db_get_value((int) &(*fp)->f_retaddr, 4, FALSE);
 278         ebp = db_get_value((int) &(*fp)->f_frame, 4, FALSE);
 279
 280         /*
 281          * Figure out frame type.  We look at the address just before
 282          * the saved instruction pointer as the saved EIP is after the
 283          * call function, and if the function being called is marked as
 284          * dead (such as panic() at the end of dblfault_handler()), then
 285          * the instruction at the saved EIP will be part of a different
 286          * function (syscall() in this example) rather than the one that
 287          * actually made the call.
 288          */
 289         frame_type = NORMAL;
 290         sym = db_search_symbol(eip - 1, DB_STGY_ANY, &offset);
 291         db_symbol_values(sym, &name, NULL);
 292         if (name != NULL) {
 293                 if (strcmp(name, "calltrap") == 0 ||
 294                     strcmp(name, "fork_trampoline") == 0)
 295                         frame_type = TRAP;
 296                 else if (strncmp(name, "Xatpic_intr", 11) == 0 ||
 297                     strncmp(name, "Xapic_isr", 9) == 0)
 298                         frame_type = INTERRUPT;
 299                 else if (strcmp(name, "Xlcall_syscall") == 0 ||
 300                     strcmp(name, "Xint0x80_syscall") == 0)
 301                         frame_type = SYSCALL;
 302                 else if (strcmp(name, "dblfault_handler") == 0)
 303                         frame_type = DOUBLE_FAULT;
 304                 /* XXX: These are interrupts with trap frames. */
 305                 else if (strcmp(name, "Xtimerint") == 0)
 306                         frame_type = TRAP_TIMERINT;
 307                 else if (strcmp(name, "Xcpustop") == 0 ||
 308                     strcmp(name, "Xrendezvous") == 0 ||
 309                     strcmp(name, "Xipi_intr_bitmap_handler") == 0)
 310                         frame_type = TRAP_INTERRUPT;
 311         }
 312
 313         /*
 314          * Normal frames need no special processing.
 315          */
 316         if (frame_type == NORMAL) {
 317                 *ip = (db_addr_t) eip;
 318                 *fp = (struct i386_frame *) ebp;
 319                 return;
 320         }
 321
 322         db_print_stack_entry(name, 0, 0, 0, eip, &(*fp)->f_frame);
 323
 324         /*
 325          * For a double fault, we have to snag the values from the
 326          * previous TSS since a double fault uses a task gate to
 327          * switch to a known good state.
 328          */
 329         if (frame_type == DOUBLE_FAULT) {
 330                 esp = PCPU_GET(common_tss.tss_esp);
 331                 eip = PCPU_GET(common_tss.tss_eip);
 332                 ebp = PCPU_GET(common_tss.tss_ebp);
 333                 db_printf(
 334                     "--- trap 0x17, eip = %#r, esp = %#r, ebp = %#r ---\n",
 335                     eip, esp, ebp);
 336                 *ip = (db_addr_t) eip;
 337                 *fp = (struct i386_frame *) ebp;
 338                 return;
 339         }
 340
 341         /*
 342          * Point to base of trapframe which is just above the
 343          * current frame.
 344          */
 345         if (frame_type == INTERRUPT)
 346                 tf = (struct trapframe *)((int)*fp + 16);
 347         else if (frame_type == TRAP_INTERRUPT)
 348                 tf = (struct trapframe *)((int)*fp + 8);
 349         else
 350                 tf = (struct trapframe *)((int)*fp + 12);
 351
 352         if (INKERNEL((int) tf)) {
 353                 esp = get_esp(tf);
 354                 eip = tf->tf_eip;
 355                 ebp = tf->tf_ebp;
 356                 switch (frame_type) {
 357                 case TRAP:
 358                         db_printf("--- trap %#r", tf->tf_trapno);
 359                         break;
 360                 case SYSCALL:
 361                         db_printf("--- syscall");
 362                         decode_syscall(tf->tf_eax, td);
 363                         break;
 364                 case TRAP_TIMERINT:
 365                 case TRAP_INTERRUPT:
 366                 case INTERRUPT:
 367                         db_printf("--- interrupt");
 368                         break;
 369                 default:
 370                         panic("The moon has moved again.");
 371                 }
 372                 db_printf(", eip = %#r, esp = %#r, ebp = %#r ---\n", eip,
 373                     esp, ebp);
 374         }
 375
 376         *ip = (db_addr_t) eip;
 377         *fp = (struct i386_frame *) ebp;
 378 }
 379
 380 static int
 381 db_backtrace(struct thread *td, struct trapframe *tf, struct i386_frame *frame,
 382     db_addr_t pc, register_t sp, int count)
 383 {
 384         struct i386_frame *actframe;
 385 #define MAXNARG 16
 386         char *argnames[MAXNARG], **argnp = NULL;
 387         const char *name;
 388         int *argp;
 389         db_expr_t offset;
 390         c_db_sym_t sym;
 391         int instr, narg;
 392         boolean_t first;
 393
 394         /*
 395          * If an indirect call via an invalid pointer caused a trap,
 396          * %pc contains the invalid address while the return address
 397          * of the unlucky caller has been saved by CPU on the stack
 398          * just before the trap frame.  In this case, try to recover
 399          * the caller's address so that the first frame is assigned
 400          * to the right spot in the right function, for that is where
 401          * the failure actually happened.
 402          *
 403          * This trick depends on the fault address stashed in tf_err
 404          * by trap_fatal() before entering KDB.
 405          */
 406         if (kdb_frame && pc == kdb_frame->tf_err) {
 407                 /*
 408                  * Find where the trap frame actually ends.
 409                  * It won't contain tf_esp or tf_ss unless crossing rings.
 410                  */
 411                 if (ISPL(kdb_frame->tf_cs))
 412                         instr = (int)(kdb_frame + 1);
 413                 else
 414                         instr = (int)&kdb_frame->tf_esp;
 415                 pc = db_get_value(instr, 4, FALSE);
 416         }
 417
 418         if (count == -1)
 419                 count = 1024;
 420
 421         first = TRUE;
 422         while (count-- && !db_pager_quit) {
 423                 sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
 424                 db_symbol_values(sym, &name, NULL);
 425
 426                 /*
 427                  * Attempt to determine a (possibly fake) frame that gives
 428                  * the caller's pc.  It may differ from `frame' if the
 429                  * current function never sets up a standard frame or hasn't
 430                  * set one up yet or has just discarded one.  The last two
 431                  * cases can be guessed fairly reliably for code generated
 432                  * by gcc.  The first case is too much trouble to handle in
 433                  * general because the amount of junk on the stack depends
 434                  * on the pc (the special handling of "calltrap", etc. in
 435                  * db_nextframe() works because the `next' pc is special).
 436                  */
 437                 actframe = frame;
 438                 if (first) {
 439                         first = FALSE;
 440                         if (sym == C_DB_SYM_NULL && sp != 0) {
 441                                 /*
 442                                  * If a symbol couldn't be found, we've probably
 443                                  * jumped to a bogus location, so try and use
 444                                  * the return address to find our caller.
 445                                  */
 446                                 db_print_stack_entry(name, 0, 0, 0, pc,
 447                                     NULL);
 448                                 pc = db_get_value(sp, 4, FALSE);
 449                                 if (db_search_symbol(pc, DB_STGY_PROC,
 450                                     &offset) == C_DB_SYM_NULL)
 451                                         break;
 452                                 continue;
 453                         } else if (tf != NULL) {
 454                                 instr = db_get_value(pc, 4, FALSE);
 455                                 if ((instr & 0xffffff) == 0x00e58955) {
 456                                         /* pushl %ebp; movl %esp, %ebp */
 457                                         actframe = (void *)(get_esp(tf) - 4);
 458                                 } else if ((instr & 0xffff) == 0x0000e589) {
 459                                         /* movl %esp, %ebp */
 460                                         actframe = (void *)get_esp(tf);
 461                                         if (tf->tf_ebp == 0) {
 462                                                 /* Fake frame better. */
 463                                                 frame = actframe;
 464                                         }
 465                                 } else if ((instr & 0xff) == 0x000000c3) {
 466                                         /* ret */
 467                                         actframe = (void *)(get_esp(tf) - 4);
 468                                 } else if (offset == 0) {
 469                                         /* Probably an assembler symbol. */
 470                                         actframe = (void *)(get_esp(tf) - 4);
 471                                 }
 472                         } else if (strcmp(name, "fork_trampoline") == 0) {
 473                                 /*
 474                                  * Don't try to walk back on a stack for a
 475                                  * process that hasn't actually been run yet.
 476                                  */
 477                                 db_print_stack_entry(name, 0, 0, 0, pc,
 478                                     actframe);
 479                                 break;
 480                         }
 481                 }
 482
 483                 argp = &actframe->f_arg0;
 484                 narg = MAXNARG;
 485                 if (sym != NULL && db_sym_numargs(sym, &narg, argnames)) {
 486                         argnp = argnames;
 487                 } else {
 488                         narg = db_numargs(frame);
 489                 }
 490
 491                 db_print_stack_entry(name, narg, argnp, argp, pc, actframe);
 492
 493                 if (actframe != frame) {
 494                         /* `frame' belongs to caller. */
 495                         pc = (db_addr_t)
 496                             db_get_value((int)&actframe->f_retaddr, 4, FALSE);
 497                         continue;
 498                 }
 499
 500                 db_nextframe(&frame, &pc, td);
 501
 502                 if (INKERNEL((int)pc) && !INKERNEL((int) frame)) {
 503                         sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
 504                         db_symbol_values(sym, &name, NULL);
 505                         db_print_stack_entry(name, 0, 0, 0, pc, frame);
 506                         break;
 507                 }
 508                 if (!INKERNEL((int) frame)) {
 509                         break;
 510                 }
 511         }
 512
 513         return (0);
 514 }
 515
 516 void
 517 db_trace_self(void)
 518 {
 519         struct i386_frame *frame;
 520         db_addr_t callpc;
 521         register_t ebp;
 522
 523         __asm __volatile("movl %%ebp,%0" : "=r" (ebp));
 524         frame = (struct i386_frame *)ebp;
 525         callpc = (db_addr_t)db_get_value((int)&frame->f_retaddr, 4, FALSE);
 526         frame = frame->f_frame;
 527         db_backtrace(curthread, NULL, frame, callpc, 0, -1);
 528 }
 529
 530 int
 531 db_trace_thread(struct thread *thr, int count)
 532 {
 533         struct pcb *ctx;
 534         struct trapframe *tf;
 535
 536         ctx = kdb_thr_ctx(thr);
 537         tf = thr == kdb_thread ? kdb_frame : NULL;
 538         return (db_backtrace(thr, tf, (struct i386_frame *)ctx->pcb_ebp,
 539             ctx->pcb_eip, ctx->pcb_esp, count));
 540 }
 541
 542 int
 543 i386_set_watch(watchnum, watchaddr, size, access, d)
 544         int watchnum;
 545         unsigned int watchaddr;
 546         int size;
 547         int access;
 548         struct dbreg *d;
 549 {
 550         int i, len;
 551
 552         if (watchnum == -1) {
 553                 for (i = 0; i < 4; i++)
 554                         if (!DBREG_DR7_ENABLED(d->dr[7], i))
 555                                 break;
 556                 if (i < 4)
 557                         watchnum = i;
 558                 else
 559                         return (-1);
 560         }
 561
 562         switch (access) {
 563         case DBREG_DR7_EXEC:
 564                 size = 1; /* size must be 1 for an execution breakpoint */
 565                 /* fall through */
 566         case DBREG_DR7_WRONLY:
 567         case DBREG_DR7_RDWR:
 568                 break;
 569         default:
 570                 return (-1);
 571         }
 572
 573         /*
 574          * we can watch a 1, 2, or 4 byte sized location
 575          */
 576         switch (size) {
 577         case 1:
 578                 len = DBREG_DR7_LEN_1;
 579                 break;
 580         case 2:
 581                 len = DBREG_DR7_LEN_2;
 582                 break;
 583         case 4:
 584                 len = DBREG_DR7_LEN_4;
 585                 break;
 586         default:
 587                 return (-1);
 588         }
 589
 590         /* clear the bits we are about to affect */
 591         d->dr[7] &= ~DBREG_DR7_MASK(watchnum);
 592
 593         /* set drN register to the address, N=watchnum */
 594         DBREG_DRX(d, watchnum) = watchaddr;
 595
 596         /* enable the watchpoint */
 597         d->dr[7] |= DBREG_DR7_SET(watchnum, len, access,
 598             DBREG_DR7_GLOBAL_ENABLE);
 599
 600         return (watchnum);
 601 }
 602
 603
 604 int
 605 i386_clr_watch(watchnum, d)
 606         int watchnum;
 607         struct dbreg *d;
 608 {
 609
 610         if (watchnum < 0 || watchnum >= 4)
 611                 return (-1);
 612
 613         d->dr[7] &= ~DBREG_DR7_MASK(watchnum);
 614         DBREG_DRX(d, watchnum) = 0;
 615
 616         return (0);
 617 }
 618
 619
 620 int
 621 db_md_set_watchpoint(addr, size)
 622         db_expr_t addr;
 623         db_expr_t size;
 624 {
 625         struct dbreg d;
 626         int avail, i, wsize;
 627
 628         fill_dbregs(NULL, &d);
 629
 630         avail = 0;
 631         for(i = 0; i < 4; i++) {
 632                 if (!DBREG_DR7_ENABLED(d.dr[7], i))
 633                         avail++;
 634         }
 635
 636         if (avail * 4 < size)
 637                 return (-1);
 638
 639         for (i = 0; i < 4 && (size > 0); i++) {
 640                 if (!DBREG_DR7_ENABLED(d.dr[7], i)) {
 641                         if (size > 2)
 642                                 wsize = 4;
 643                         else
 644                                 wsize = size;
 645                         i386_set_watch(i, addr, wsize,
 646                                        DBREG_DR7_WRONLY, &d);
 647                         addr += wsize;
 648                         size -= wsize;
 649                 }
 650         }
 651
 652         set_dbregs(NULL, &d);
 653
 654         return(0);
 655 }
 656
 657
 658 int
 659 db_md_clr_watchpoint(addr, size)
 660         db_expr_t addr;
 661         db_expr_t size;
 662 {
 663         struct dbreg d;
 664         int i;
 665
 666         fill_dbregs(NULL, &d);
 667
 668         for(i = 0; i < 4; i++) {
 669                 if (DBREG_DR7_ENABLED(d.dr[7], i)) {
 670                         if ((DBREG_DRX((&d), i) >= addr) &&
 671                             (DBREG_DRX((&d), i) < addr+size))
 672                                 i386_clr_watch(i, &d);
 673
 674                 }
 675         }
 676
 677         set_dbregs(NULL, &d);
 678
 679         return(0);
 680 }
 681
 682
 683 static const char *
 684 watchtype_str(type)
 685         int type;
 686 {
 687         switch (type) {
 688                 case DBREG_DR7_EXEC   : return "execute";    break;
 689                 case DBREG_DR7_RDWR   : return "read/write"; break;
 690                 case DBREG_DR7_WRONLY : return "write";      break;
 691                 default               : return "invalid";    break;
 692         }
 693 }
 694
 695
 696 void
 697 db_md_list_watchpoints()
 698 {
 699         struct dbreg d;
 700         int i, len, type;
 701
 702         fill_dbregs(NULL, &d);
 703
 704         db_printf("\nhardware watchpoints:\n");
 705         db_printf("  watch    status        type  len     address\n");
 706         db_printf("  -----  --------  ----------  ---  ----------\n");
 707         for (i = 0; i < 4; i++) {
 708                 if (DBREG_DR7_ENABLED(d.dr[7], i)) {
 709                         type = DBREG_DR7_ACCESS(d.dr[7], i);
 710                         len = DBREG_DR7_LEN(d.dr[7], i);
 711                         db_printf("  %-5d  %-8s  %10s  %3d  ",
 712                             i, "enabled", watchtype_str(type), len + 1);
 713                         db_printsym((db_addr_t)DBREG_DRX((&d), i), DB_STGY_ANY);
 714                         db_printf("\n");
 715                 } else {
 716                         db_printf("  %-5d  disabled\n", i);
 717                 }
 718         }
 719
 720         db_printf("\ndebug register values:\n");
 721         for (i = 0; i < 8; i++) {
 722                 db_printf("  dr%d 0x%08x\n", i, DBREG_DRX((&d), i));
 723         }
 724         db_printf("\n");
 725 }
 726
 727