arch/sparc64/kernel/ptrace.c

   1 /* ptrace.c: Sparc process tracing support.
   2  *
   3  * Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu)
   4  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   5  *
   6  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
   7  * and David Mosberger.
   8  *
   9  * Added Linux support -miguel (weird, eh?, the original code was meant
  10  * to emulate SunOS).
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/sched.h>
  15 #include <linux/mm.h>
  16 #include <linux/errno.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/user.h>
  19 #include <linux/smp.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/security.h>
  22
  23 #include <asm/asi.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/system.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/psrcompat.h>
  28 #include <asm/visasm.h>
  29 #include <asm/spitfire.h>
  30
  31 /* Returning from ptrace is a bit tricky because the syscall return
  32  * low level code assumes any value returned which is negative and
  33  * is a valid errno will mean setting the condition codes to indicate
  34  * an error return.  This doesn't work, so we have this hook.
  35  */
  36 static inline void pt_error_return(struct pt_regs *regs, unsigned long error)
  37 {
  38         regs->u_regs[UREG_I0] = error;
  39         regs->tstate |= (TSTATE_ICARRY | TSTATE_XCARRY);
  40         regs->tpc = regs->tnpc;
  41         regs->tnpc += 4;
  42 }
  43
  44 static inline void pt_succ_return(struct pt_regs *regs, unsigned long value)
  45 {
  46         regs->u_regs[UREG_I0] = value;
  47         regs->tstate &= ~(TSTATE_ICARRY | TSTATE_XCARRY);
  48         regs->tpc = regs->tnpc;
  49         regs->tnpc += 4;
  50 }
  51
  52 static inline void
  53 pt_succ_return_linux(struct pt_regs *regs, unsigned long value, void __user *addr)
  54 {
  55         if (test_thread_flag(TIF_32BIT)) {
  56                 if (put_user(value, (unsigned int __user *) addr)) {
  57                         pt_error_return(regs, EFAULT);
  58                         return;
  59                 }
  60         } else {
  61                 if (put_user(value, (long __user *) addr)) {
  62                         pt_error_return(regs, EFAULT);
  63                         return;
  64                 }
  65         }
  66         regs->u_regs[UREG_I0] = 0;
  67         regs->tstate &= ~(TSTATE_ICARRY | TSTATE_XCARRY);
  68         regs->tpc = regs->tnpc;
  69         regs->tnpc += 4;
  70 }
  71
  72 static void
  73 pt_os_succ_return (struct pt_regs *regs, unsigned long val, void __user *addr)
  74 {
  75         if (current->personality == PER_SUNOS)
  76                 pt_succ_return (regs, val);
  77         else
  78                 pt_succ_return_linux (regs, val, addr);
  79 }
  80
  81 /* #define ALLOW_INIT_TRACING */
  82 /* #define DEBUG_PTRACE */
  83
  84 #ifdef DEBUG_PTRACE
  85 char *pt_rq [] = {
  86         /* 0  */ "TRACEME", "PEEKTEXT", "PEEKDATA", "PEEKUSR",
  87         /* 4  */ "POKETEXT", "POKEDATA", "POKEUSR", "CONT",
  88         /* 8  */ "KILL", "SINGLESTEP", "SUNATTACH", "SUNDETACH",
  89         /* 12 */ "GETREGS", "SETREGS", "GETFPREGS", "SETFPREGS",
  90         /* 16 */ "READDATA", "WRITEDATA", "READTEXT", "WRITETEXT",
  91         /* 20 */ "GETFPAREGS", "SETFPAREGS", "unknown", "unknown",
  92         /* 24 */ "SYSCALL", ""
  93 };
  94 #endif
  95
  96 /*
  97  * Called by kernel/ptrace.c when detaching..
  98  *
  99  * Make sure single step bits etc are not set.
 100  */
 101 void ptrace_disable(struct task_struct *child)
 102 {
 103         /* nothing to do */
 104 }
 105
 106 asmlinkage void do_ptrace(struct pt_regs *regs)
 107 {
 108         int request = regs->u_regs[UREG_I0];
 109         pid_t pid = regs->u_regs[UREG_I1];
 110         unsigned long addr = regs->u_regs[UREG_I2];
 111         unsigned long data = regs->u_regs[UREG_I3];
 112         unsigned long addr2 = regs->u_regs[UREG_I4];
 113         struct task_struct *child;
 114         int ret;
 115
 116         if (test_thread_flag(TIF_32BIT)) {
 117                 addr &= 0xffffffffUL;
 118                 data &= 0xffffffffUL;
 119                 addr2 &= 0xffffffffUL;
 120         }
 121         lock_kernel();
 122 #ifdef DEBUG_PTRACE
 123         {
 124                 char *s;
 125
 126                 if ((request >= 0) && (request <= 24))
 127                         s = pt_rq [request];
 128                 else
 129                         s = "unknown";
 130
 131                 if (request == PTRACE_POKEDATA && data == 0x91d02001){
 132                         printk ("do_ptrace: breakpoint pid=%d, addr=%016lx addr2=%016lx\n",
 133                                 pid, addr, addr2);
 134                 } else
 135                         printk("do_ptrace: rq=%s(%d) pid=%d addr=%016lx data=%016lx addr2=%016lx\n",
 136                                s, request, pid, addr, data, addr2);
 137         }
 138 #endif
 139         if (request == PTRACE_TRACEME) {
 140                 int ret;
 141
 142                 /* are we already being traced? */
 143                 if (current->ptrace & PT_PTRACED) {
 144                         pt_error_return(regs, EPERM);
 145                         goto out;
 146                 }
 147                 ret = security_ptrace(current->parent, current);
 148                 if (ret) {
 149                         pt_error_return(regs, -ret);
 150                         goto out;
 151                 }
 152
 153                 /* set the ptrace bit in the process flags. */
 154                 current->ptrace |= PT_PTRACED;
 155                 pt_succ_return(regs, 0);
 156                 goto out;
 157         }
 158 #ifndef ALLOW_INIT_TRACING
 159         if (pid == 1) {
 160                 /* Can't dork with init. */
 161                 pt_error_return(regs, EPERM);
 162                 goto out;
 163         }
 164 #endif
 165         read_lock(&tasklist_lock);
 166         child = find_task_by_pid(pid);
 167         if (child)
 168                 get_task_struct(child);
 169         read_unlock(&tasklist_lock);
 170
 171         if (!child) {
 172                 pt_error_return(regs, ESRCH);
 173                 goto out;
 174         }
 175         if (!vx_check(vx_task_xid(child), VX_WATCH|VX_IDENT)) {
 176                 pt_error_return(regs, ESRCH);
 177                 goto out_tsk;
 178         }
 179
 180         if ((current->personality == PER_SUNOS && request == PTRACE_SUNATTACH)
 181             || (current->personality != PER_SUNOS && request == PTRACE_ATTACH)) {
 182                 if (ptrace_attach(child)) {
 183                         pt_error_return(regs, EPERM);
 184                         goto out_tsk;
 185                 }
 186                 pt_succ_return(regs, 0);
 187                 goto out_tsk;
 188         }
 189
 190         ret = ptrace_check_attach(child, request == PTRACE_KILL);
 191         if (ret < 0) {
 192                 pt_error_return(regs, -ret);
 193                 goto out_tsk;
 194         }
 195
 196         if (!(test_thread_flag(TIF_32BIT))      &&
 197             ((request == PTRACE_READDATA64)             ||
 198              (request == PTRACE_WRITEDATA64)            ||
 199              (request == PTRACE_READTEXT64)             ||
 200              (request == PTRACE_WRITETEXT64)            ||
 201              (request == PTRACE_PEEKTEXT64)             ||
 202              (request == PTRACE_POKETEXT64)             ||
 203              (request == PTRACE_PEEKDATA64)             ||
 204              (request == PTRACE_POKEDATA64))) {
 205                 addr = regs->u_regs[UREG_G2];
 206                 addr2 = regs->u_regs[UREG_G3];
 207                 request -= 30; /* wheee... */
 208         }
 209
 210         switch(request) {
 211         case PTRACE_PEEKTEXT: /* read word at location addr. */
 212         case PTRACE_PEEKDATA: {
 213                 unsigned long tmp64;
 214                 unsigned int tmp32;
 215                 int res, copied;
 216
 217                 res = -EIO;
 218                 if (test_thread_flag(TIF_32BIT)) {
 219                         copied = access_process_vm(child, addr,
 220                                                    &tmp32, sizeof(tmp32), 0);
 221                         tmp64 = (unsigned long) tmp32;
 222                         if (copied == sizeof(tmp32))
 223                                 res = 0;
 224                 } else {
 225                         copied = access_process_vm(child, addr,
 226                                                    &tmp64, sizeof(tmp64), 0);
 227                         if (copied == sizeof(tmp64))
 228                                 res = 0;
 229                 }
 230                 if (res < 0)
 231                         pt_error_return(regs, -res);
 232                 else
 233                         pt_os_succ_return(regs, tmp64, (void __user *) data);
 234                 goto flush_and_out;
 235         }
 236
 237         case PTRACE_POKETEXT: /* write the word at location addr. */
 238         case PTRACE_POKEDATA: {
 239                 unsigned long tmp64;
 240                 unsigned int tmp32;
 241                 int copied, res = -EIO;
 242
 243                 if (test_thread_flag(TIF_32BIT)) {
 244                         tmp32 = data;
 245                         copied = access_process_vm(child, addr,
 246                                                    &tmp32, sizeof(tmp32), 1);
 247                         if (copied == sizeof(tmp32))
 248                                 res = 0;
 249                 } else {
 250                         tmp64 = data;
 251                         copied = access_process_vm(child, addr,
 252                                                    &tmp64, sizeof(tmp64), 1);
 253                         if (copied == sizeof(tmp64))
 254                                 res = 0;
 255                 }
 256                 if (res < 0)
 257                         pt_error_return(regs, -res);
 258                 else
 259                         pt_succ_return(regs, res);
 260                 goto flush_and_out;
 261         }
 262
 263         case PTRACE_GETREGS: {
 264                 struct pt_regs32 __user *pregs =
 265                         (struct pt_regs32 __user *) addr;
 266                 struct pt_regs *cregs = child->thread_info->kregs;
 267                 int rval;
 268
 269                 if (__put_user(tstate_to_psr(cregs->tstate), (&pregs->psr)) ||
 270                     __put_user(cregs->tpc, (&pregs->pc)) ||
 271                     __put_user(cregs->tnpc, (&pregs->npc)) ||
 272                     __put_user(cregs->y, (&pregs->y))) {
 273                         pt_error_return(regs, EFAULT);
 274                         goto out_tsk;
 275                 }
 276                 for (rval = 1; rval < 16; rval++)
 277                         if (__put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]))) {
 278                                 pt_error_return(regs, EFAULT);
 279                                 goto out_tsk;
 280                         }
 281                 pt_succ_return(regs, 0);
 282 #ifdef DEBUG_PTRACE
 283                 printk ("PC=%lx nPC=%lx o7=%lx\n", cregs->tpc, cregs->tnpc, cregs->u_regs [15]);
 284 #endif
 285                 goto out_tsk;
 286         }
 287
 288         case PTRACE_GETREGS64: {
 289                 struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
 290                 struct pt_regs *cregs = child->thread_info->kregs;
 291                 unsigned long tpc = cregs->tpc;
 292                 int rval;
 293
 294                 if ((child->thread_info->flags & _TIF_32BIT) != 0)
 295                         tpc &= 0xffffffff;
 296                 if (__put_user(cregs->tstate, (&pregs->tstate)) ||
 297                     __put_user(tpc, (&pregs->tpc)) ||
 298                     __put_user(cregs->tnpc, (&pregs->tnpc)) ||
 299                     __put_user(cregs->y, (&pregs->y))) {
 300                         pt_error_return(regs, EFAULT);
 301                         goto out_tsk;
 302                 }
 303                 for (rval = 1; rval < 16; rval++)
 304                         if (__put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]))) {
 305                                 pt_error_return(regs, EFAULT);
 306                                 goto out_tsk;
 307                         }
 308                 pt_succ_return(regs, 0);
 309 #ifdef DEBUG_PTRACE
 310                 printk ("PC=%lx nPC=%lx o7=%lx\n", cregs->tpc, cregs->tnpc, cregs->u_regs [15]);
 311 #endif
 312                 goto out_tsk;
 313         }
 314
 315         case PTRACE_SETREGS: {
 316                 struct pt_regs32 __user *pregs =
 317                         (struct pt_regs32 __user *) addr;
 318                 struct pt_regs *cregs = child->thread_info->kregs;
 319                 unsigned int psr, pc, npc, y;
 320                 int i;
 321
 322                 /* Must be careful, tracing process can only set certain
 323                  * bits in the psr.
 324                  */
 325                 if (__get_user(psr, (&pregs->psr)) ||
 326                     __get_user(pc, (&pregs->pc)) ||
 327                     __get_user(npc, (&pregs->npc)) ||
 328                     __get_user(y, (&pregs->y))) {
 329                         pt_error_return(regs, EFAULT);
 330                         goto out_tsk;
 331                 }
 332                 cregs->tstate &= ~(TSTATE_ICC);
 333                 cregs->tstate |= psr_to_tstate_icc(psr);
 334                 if (!((pc | npc) & 3)) {
 335                         cregs->tpc = pc;
 336                         cregs->tnpc = npc;
 337                 }
 338                 cregs->y = y;
 339                 for (i = 1; i < 16; i++) {
 340                         if (__get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]))) {
 341                                 pt_error_return(regs, EFAULT);
 342                                 goto out_tsk;
 343                         }
 344                 }
 345                 pt_succ_return(regs, 0);
 346                 goto out_tsk;
 347         }
 348
 349         case PTRACE_SETREGS64: {
 350                 struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
 351                 struct pt_regs *cregs = child->thread_info->kregs;
 352                 unsigned long tstate, tpc, tnpc, y;
 353                 int i;
 354
 355                 /* Must be careful, tracing process can only set certain
 356                  * bits in the psr.
 357                  */
 358                 if (__get_user(tstate, (&pregs->tstate)) ||
 359                     __get_user(tpc, (&pregs->tpc)) ||
 360                     __get_user(tnpc, (&pregs->tnpc)) ||
 361                     __get_user(y, (&pregs->y))) {
 362                         pt_error_return(regs, EFAULT);
 363                         goto out_tsk;
 364                 }
 365                 if ((child->thread_info->flags & _TIF_32BIT) != 0) {
 366                         tpc &= 0xffffffff;
 367                         tnpc &= 0xffffffff;
 368                 }
 369                 tstate &= (TSTATE_ICC | TSTATE_XCC);
 370                 cregs->tstate &= ~(TSTATE_ICC | TSTATE_XCC);
 371                 cregs->tstate |= tstate;
 372                 if (!((tpc | tnpc) & 3)) {
 373                         cregs->tpc = tpc;
 374                         cregs->tnpc = tnpc;
 375                 }
 376                 cregs->y = y;
 377                 for (i = 1; i < 16; i++) {
 378                         if (__get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]))) {
 379                                 pt_error_return(regs, EFAULT);
 380                                 goto out_tsk;
 381                         }
 382                 }
 383                 pt_succ_return(regs, 0);
 384                 goto out_tsk;
 385         }
 386
 387         case PTRACE_GETFPREGS: {
 388                 struct fps {
 389                         unsigned int regs[32];
 390                         unsigned int fsr;
 391                         unsigned int flags;
 392                         unsigned int extra;
 393                         unsigned int fpqd;
 394                         struct fq {
 395                                 unsigned int insnaddr;
 396                                 unsigned int insn;
 397                         } fpq[16];
 398                 };
 399                 struct fps __user *fps = (struct fps __user *) addr;
 400                 unsigned long *fpregs = child->thread_info->fpregs;
 401
 402                 if (copy_to_user(&fps->regs[0], fpregs,
 403                                  (32 * sizeof(unsigned int))) ||
 404                     __put_user(child->thread_info->xfsr[0], (&fps->fsr)) ||
 405                     __put_user(0, (&fps->fpqd)) ||
 406                     __put_user(0, (&fps->flags)) ||
 407                     __put_user(0, (&fps->extra)) ||
 408                     clear_user(&fps->fpq[0], 32 * sizeof(unsigned int))) {
 409                         pt_error_return(regs, EFAULT);
 410                         goto out_tsk;
 411                 }
 412                 pt_succ_return(regs, 0);
 413                 goto out_tsk;
 414         }
 415
 416         case PTRACE_GETFPREGS64: {
 417                 struct fps {
 418                         unsigned int regs[64];
 419                         unsigned long fsr;
 420                 };
 421                 struct fps __user *fps = (struct fps __user *) addr;
 422                 unsigned long *fpregs = child->thread_info->fpregs;
 423
 424                 if (copy_to_user(&fps->regs[0], fpregs,
 425                                  (64 * sizeof(unsigned int))) ||
 426                     __put_user(child->thread_info->xfsr[0], (&fps->fsr))) {
 427                         pt_error_return(regs, EFAULT);
 428                         goto out_tsk;
 429                 }
 430                 pt_succ_return(regs, 0);
 431                 goto out_tsk;
 432         }
 433
 434         case PTRACE_SETFPREGS: {
 435                 struct fps {
 436                         unsigned int regs[32];
 437                         unsigned int fsr;
 438                         unsigned int flags;
 439                         unsigned int extra;
 440                         unsigned int fpqd;
 441                         struct fq {
 442                                 unsigned int insnaddr;
 443                                 unsigned int insn;
 444                         } fpq[16];
 445                 };
 446                 struct fps __user *fps = (struct fps __user *) addr;
 447                 unsigned long *fpregs = child->thread_info->fpregs;
 448                 unsigned fsr;
 449
 450                 if (copy_from_user(fpregs, &fps->regs[0],
 451                                    (32 * sizeof(unsigned int))) ||
 452                     __get_user(fsr, (&fps->fsr))) {
 453                         pt_error_return(regs, EFAULT);
 454                         goto out_tsk;
 455                 }
 456                 child->thread_info->xfsr[0] &= 0xffffffff00000000UL;
 457                 child->thread_info->xfsr[0] |= fsr;
 458                 if (!(child->thread_info->fpsaved[0] & FPRS_FEF))
 459                         child->thread_info->gsr[0] = 0;
 460                 child->thread_info->fpsaved[0] |= (FPRS_FEF | FPRS_DL);
 461                 pt_succ_return(regs, 0);
 462                 goto out_tsk;
 463         }
 464
 465         case PTRACE_SETFPREGS64: {
 466                 struct fps {
 467                         unsigned int regs[64];
 468                         unsigned long fsr;
 469                 };
 470                 struct fps __user *fps = (struct fps __user *) addr;
 471                 unsigned long *fpregs = child->thread_info->fpregs;
 472
 473                 if (copy_from_user(fpregs, &fps->regs[0],
 474                                    (64 * sizeof(unsigned int))) ||
 475                     __get_user(child->thread_info->xfsr[0], (&fps->fsr))) {
 476                         pt_error_return(regs, EFAULT);
 477                         goto out_tsk;
 478                 }
 479                 if (!(child->thread_info->fpsaved[0] & FPRS_FEF))
 480                         child->thread_info->gsr[0] = 0;
 481                 child->thread_info->fpsaved[0] |= (FPRS_FEF | FPRS_DL | FPRS_DU);
 482                 pt_succ_return(regs, 0);
 483                 goto out_tsk;
 484         }
 485
 486         case PTRACE_READTEXT:
 487         case PTRACE_READDATA: {
 488                 int res = ptrace_readdata(child, addr,
 489                                           (char __user *)addr2, data);
 490                 if (res == data) {
 491                         pt_succ_return(regs, 0);
 492                         goto flush_and_out;
 493                 }
 494                 if (res >= 0)
 495                         res = -EIO;
 496                 pt_error_return(regs, -res);
 497                 goto flush_and_out;
 498         }
 499
 500         case PTRACE_WRITETEXT:
 501         case PTRACE_WRITEDATA: {
 502                 int res = ptrace_writedata(child, (char __user *) addr2,
 503                                            addr, data);
 504                 if (res == data) {
 505                         pt_succ_return(regs, 0);
 506                         goto flush_and_out;
 507                 }
 508                 if (res >= 0)
 509                         res = -EIO;
 510                 pt_error_return(regs, -res);
 511                 goto flush_and_out;
 512         }
 513         case PTRACE_SYSCALL: /* continue and stop at (return from) syscall */
 514                 addr = 1;
 515
 516         case PTRACE_CONT: { /* restart after signal. */
 517                 if (data > _NSIG) {
 518                         pt_error_return(regs, EIO);
 519                         goto out_tsk;
 520                 }
 521
 522                 if (request == PTRACE_SYSCALL) {
 523                         set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 524                 } else {
 525                         clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 526                 }
 527
 528                 child->exit_code = data;
 529 #ifdef DEBUG_PTRACE
 530                 printk("CONT: %s [%d]: set exit_code = %x %lx %lx\n", child->comm,
 531                         child->pid, child->exit_code,
 532                         child->thread_info->kregs->tpc,
 533                         child->thread_info->kregs->tnpc);
 534
 535 #endif
 536                 wake_up_process(child);
 537                 pt_succ_return(regs, 0);
 538                 goto out_tsk;
 539         }
 540
 541 /*
 542  * make the child exit.  Best I can do is send it a sigkill.
 543  * perhaps it should be put in the status that it wants to
 544  * exit.
 545  */
 546         case PTRACE_KILL: {
 547                 if (child->exit_state == EXIT_ZOMBIE) { /* already dead */
 548                         pt_succ_return(regs, 0);
 549                         goto out_tsk;
 550                 }
 551                 child->exit_code = SIGKILL;
 552                 wake_up_process(child);
 553                 pt_succ_return(regs, 0);
 554                 goto out_tsk;
 555         }
 556
 557         case PTRACE_SUNDETACH: { /* detach a process that was attached. */
 558                 int error = ptrace_detach(child, data);
 559                 if (error) {
 560                         pt_error_return(regs, EIO);
 561                         goto out_tsk;
 562                 }
 563                 pt_succ_return(regs, 0);
 564                 goto out_tsk;
 565         }
 566
 567         /* PTRACE_DUMPCORE unsupported... */
 568
 569         default: {
 570                 int err = ptrace_request(child, request, addr, data);
 571                 if (err)
 572                         pt_error_return(regs, -err);
 573                 else
 574                         pt_succ_return(regs, 0);
 575                 goto out_tsk;
 576         }
 577         }
 578 flush_and_out:
 579         {
 580                 unsigned long va;
 581
 582                 if (tlb_type == cheetah || tlb_type == cheetah_plus) {
 583                         for (va = 0; va < (1 << 16); va += (1 << 5))
 584                                 spitfire_put_dcache_tag(va, 0x0);
 585                         /* No need to mess with I-cache on Cheetah. */
 586                 } else {
 587                         for (va =  0; va < L1DCACHE_SIZE; va += 32)
 588                                 spitfire_put_dcache_tag(va, 0x0);
 589                         if (request == PTRACE_PEEKTEXT ||
 590                             request == PTRACE_POKETEXT ||
 591                             request == PTRACE_READTEXT ||
 592                             request == PTRACE_WRITETEXT) {
 593                                 for (va =  0; va < (PAGE_SIZE << 1); va += 32)
 594                                         spitfire_put_icache_tag(va, 0x0);
 595                                 __asm__ __volatile__("flush %g6");
 596                         }
 597                 }
 598         }
 599 out_tsk:
 600         if (child)
 601                 put_task_struct(child);
 602 out:
 603         unlock_kernel();
 604 }
 605
 606 asmlinkage void syscall_trace(void)
 607 {
 608 #ifdef DEBUG_PTRACE
 609         printk("%s [%d]: syscall_trace\n", current->comm, current->pid);
 610 #endif
 611         if (!test_thread_flag(TIF_SYSCALL_TRACE))
 612                 return;
 613         if (!(current->ptrace & PT_PTRACED))
 614                 return;
 615         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
 616                                  ? 0x80 : 0));
 617
 618         /*
 619          * this isn't the same as continuing with a signal, but it will do
 620          * for normal use.  strace only continues with a signal if the
 621          * stopping signal is not SIGTRAP.  -brl
 622          */
 623 #ifdef DEBUG_PTRACE
 624         printk("%s [%d]: syscall_trace exit= %x\n", current->comm,
 625                 current->pid, current->exit_code);
 626 #endif
 627         if (current->exit_code) {
 628                 send_sig (current->exit_code, current, 1);
 629                 current->exit_code = 0;
 630         }
 631 }