arch/sh/kernel/signal_32.c

   1 /*
   2  *  linux/arch/sh/kernel/signal.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *
   6  *  1997-11-28  Modified for POSIX.1b signals by Richard Henderson
   7  *
   8  *  SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
   9  *
  10  */
  11 #include <linux/sched.h>
  12 #include <linux/mm.h>
  13 #include <linux/smp.h>
  14 #include <linux/kernel.h>
  15 #include <linux/signal.h>
  16 #include <linux/errno.h>
  17 #include <linux/wait.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/unistd.h>
  20 #include <linux/stddef.h>
  21 #include <linux/tty.h>
  22 #include <linux/elf.h>
  23 #include <linux/personality.h>
  24 #include <linux/binfmts.h>
  25 #include <linux/freezer.h>
  26 #include <linux/io.h>
  27 #include <asm/system.h>
  28 #include <asm/ucontext.h>
  29 #include <asm/uaccess.h>
  30 #include <asm/pgtable.h>
  31 #include <asm/cacheflush.h>
  32 #include <asm/fpu.h>
  33
  34 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  35
  36 /*
  37  * Atomically swap in the new signal mask, and wait for a signal.
  38  */
  39 asmlinkage int
  40 sys_sigsuspend(old_sigset_t mask,
  41                unsigned long r5, unsigned long r6, unsigned long r7,
  42                struct pt_regs __regs)
  43 {
  44         mask &= _BLOCKABLE;
  45         spin_lock_irq(&current->sighand->siglock);
  46         current->saved_sigmask = current->blocked;
  47         siginitset(&current->blocked, mask);
  48         recalc_sigpending();
  49         spin_unlock_irq(&current->sighand->siglock);
  50
  51         current->state = TASK_INTERRUPTIBLE;
  52         schedule();
  53         set_thread_flag(TIF_RESTORE_SIGMASK);
  54         return -ERESTARTNOHAND;
  55 }
  56
  57 asmlinkage int
  58 sys_sigaction(int sig, const struct old_sigaction __user *act,
  59               struct old_sigaction __user *oact)
  60 {
  61         struct k_sigaction new_ka, old_ka;
  62         int ret;
  63
  64         if (act) {
  65                 old_sigset_t mask;
  66                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
  67                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
  68                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
  69                         return -EFAULT;
  70                 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
  71                 __get_user(mask, &act->sa_mask);
  72                 siginitset(&new_ka.sa.sa_mask, mask);
  73         }
  74
  75         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
  76
  77         if (!ret && oact) {
  78                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
  79                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
  80                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
  81                         return -EFAULT;
  82                 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
  83                 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
  84         }
  85
  86         return ret;
  87 }
  88
  89 asmlinkage int
  90 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
  91                 unsigned long r6, unsigned long r7,
  92                 struct pt_regs __regs)
  93 {
  94         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
  95
  96         return do_sigaltstack(uss, uoss, regs->regs[15]);
  97 }
  98
  99
 100 /*
 101  * Do a signal return; undo the signal stack.
 102  */
 103
 104 #define MOVW(n)  (0x9300|((n)-2))       /* Move mem word at PC+n to R3 */
 105 #if defined(CONFIG_CPU_SH2)
 106 #define TRAP_NOARG 0xc320               /* Syscall w/no args (NR in R3) */
 107 #else
 108 #define TRAP_NOARG 0xc310               /* Syscall w/no args (NR in R3) */
 109 #endif
 110 #define OR_R0_R0 0x200b                 /* or r0,r0 (insert to avoid hardware bug) */
 111
 112 struct sigframe
 113 {
 114         struct sigcontext sc;
 115         unsigned long extramask[_NSIG_WORDS-1];
 116         u16 retcode[8];
 117 };
 118
 119 struct rt_sigframe
 120 {
 121         struct siginfo info;
 122         struct ucontext uc;
 123         u16 retcode[8];
 124 };
 125
 126 #ifdef CONFIG_SH_FPU
 127 static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
 128 {
 129         struct task_struct *tsk = current;
 130
 131         if (!(current_cpu_data.flags & CPU_HAS_FPU))
 132                 return 0;
 133
 134         set_used_math();
 135         return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0],
 136                                 sizeof(long)*(16*2+2));
 137 }
 138
 139 static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
 140                                       struct pt_regs *regs)
 141 {
 142         struct task_struct *tsk = current;
 143
 144         if (!(current_cpu_data.flags & CPU_HAS_FPU))
 145                 return 0;
 146
 147         if (!used_math()) {
 148                 __put_user(0, &sc->sc_ownedfp);
 149                 return 0;
 150         }
 151
 152         __put_user(1, &sc->sc_ownedfp);
 153
 154         /* This will cause a "finit" to be triggered by the next
 155            attempted FPU operation by the 'current' process.
 156            */
 157         clear_used_math();
 158
 159         unlazy_fpu(tsk, regs);
 160         return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard,
 161                               sizeof(long)*(16*2+2));
 162 }
 163 #endif /* CONFIG_SH_FPU */
 164
 165 static int
 166 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
 167 {
 168         unsigned int err = 0;
 169
 170 #define COPY(x)         err |= __get_user(regs->x, &sc->sc_##x)
 171                         COPY(regs[1]);
 172         COPY(regs[2]);  COPY(regs[3]);
 173         COPY(regs[4]);  COPY(regs[5]);
 174         COPY(regs[6]);  COPY(regs[7]);
 175         COPY(regs[8]);  COPY(regs[9]);
 176         COPY(regs[10]); COPY(regs[11]);
 177         COPY(regs[12]); COPY(regs[13]);
 178         COPY(regs[14]); COPY(regs[15]);
 179         COPY(gbr);      COPY(mach);
 180         COPY(macl);     COPY(pr);
 181         COPY(sr);       COPY(pc);
 182 #undef COPY
 183
 184 #ifdef CONFIG_SH_FPU
 185         if (current_cpu_data.flags & CPU_HAS_FPU) {
 186                 int owned_fp;
 187                 struct task_struct *tsk = current;
 188
 189                 regs->sr |= SR_FD; /* Release FPU */
 190                 clear_fpu(tsk, regs);
 191                 clear_used_math();
 192                 __get_user (owned_fp, &sc->sc_ownedfp);
 193                 if (owned_fp)
 194                         err |= restore_sigcontext_fpu(sc);
 195         }
 196 #endif
 197
 198         regs->tra = -1;         /* disable syscall checks */
 199         err |= __get_user(*r0_p, &sc->sc_regs[0]);
 200         return err;
 201 }
 202
 203 asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
 204                              unsigned long r6, unsigned long r7,
 205                              struct pt_regs __regs)
 206 {
 207         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 208         struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
 209         sigset_t set;
 210         int r0;
 211
 212         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 213                 goto badframe;
 214
 215         if (__get_user(set.sig[0], &frame->sc.oldmask)
 216             || (_NSIG_WORDS > 1
 217                 && __copy_from_user(&set.sig[1], &frame->extramask,
 218                                     sizeof(frame->extramask))))
 219                 goto badframe;
 220
 221         sigdelsetmask(&set, ~_BLOCKABLE);
 222
 223         spin_lock_irq(&current->sighand->siglock);
 224         current->blocked = set;
 225         recalc_sigpending();
 226         spin_unlock_irq(&current->sighand->siglock);
 227
 228         if (restore_sigcontext(regs, &frame->sc, &r0))
 229                 goto badframe;
 230         return r0;
 231
 232 badframe:
 233         force_sig(SIGSEGV, current);
 234         return 0;
 235 }
 236
 237 asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
 238                                 unsigned long r6, unsigned long r7,
 239                                 struct pt_regs __regs)
 240 {
 241         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 242         struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
 243         sigset_t set;
 244         stack_t st;
 245         int r0;
 246
 247         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 248                 goto badframe;
 249
 250         if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 251                 goto badframe;
 252
 253         sigdelsetmask(&set, ~_BLOCKABLE);
 254         spin_lock_irq(&current->sighand->siglock);
 255         current->blocked = set;
 256         recalc_sigpending();
 257         spin_unlock_irq(&current->sighand->siglock);
 258
 259         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
 260                 goto badframe;
 261
 262         if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
 263                 goto badframe;
 264         /* It is more difficult to avoid calling this function than to
 265            call it and ignore errors.  */
 266         do_sigaltstack((const stack_t __user *)&st, NULL, (unsigned long)frame);
 267
 268         return r0;
 269
 270 badframe:
 271         force_sig(SIGSEGV, current);
 272         return 0;
 273 }
 274
 275 /*
 276  * Set up a signal frame.
 277  */
 278
 279 static int
 280 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
 281                  unsigned long mask)
 282 {
 283         int err = 0;
 284
 285 #define COPY(x)         err |= __put_user(regs->x, &sc->sc_##x)
 286         COPY(regs[0]);  COPY(regs[1]);
 287         COPY(regs[2]);  COPY(regs[3]);
 288         COPY(regs[4]);  COPY(regs[5]);
 289         COPY(regs[6]);  COPY(regs[7]);
 290         COPY(regs[8]);  COPY(regs[9]);
 291         COPY(regs[10]); COPY(regs[11]);
 292         COPY(regs[12]); COPY(regs[13]);
 293         COPY(regs[14]); COPY(regs[15]);
 294         COPY(gbr);      COPY(mach);
 295         COPY(macl);     COPY(pr);
 296         COPY(sr);       COPY(pc);
 297 #undef COPY
 298
 299 #ifdef CONFIG_SH_FPU
 300         err |= save_sigcontext_fpu(sc, regs);
 301 #endif
 302
 303         /* non-iBCS2 extensions.. */
 304         err |= __put_user(mask, &sc->oldmask);
 305
 306         return err;
 307 }
 308
 309 /*
 310  * Determine which stack to use..
 311  */
 312 static inline void __user *
 313 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
 314 {
 315         if (ka->sa.sa_flags & SA_ONSTACK) {
 316                 if (sas_ss_flags(sp) == 0)
 317                         sp = current->sas_ss_sp + current->sas_ss_size;
 318         }
 319
 320         return (void __user *)((sp - frame_size) & -8ul);
 321 }
 322
 323 /* These symbols are defined with the addresses in the vsyscall page.
 324    See vsyscall-trapa.S.  */
 325 extern void __user __kernel_sigreturn;
 326 extern void __user __kernel_rt_sigreturn;
 327
 328 static int setup_frame(int sig, struct k_sigaction *ka,
 329                         sigset_t *set, struct pt_regs *regs)
 330 {
 331         struct sigframe __user *frame;
 332         int err = 0;
 333         int signal;
 334
 335         frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
 336
 337         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 338                 goto give_sigsegv;
 339
 340         signal = current_thread_info()->exec_domain
 341                 && current_thread_info()->exec_domain->signal_invmap
 342                 && sig < 32
 343                 ? current_thread_info()->exec_domain->signal_invmap[sig]
 344                 : sig;
 345
 346         err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
 347
 348         if (_NSIG_WORDS > 1)
 349                 err |= __copy_to_user(frame->extramask, &set->sig[1],
 350                                       sizeof(frame->extramask));
 351
 352         /* Set up to return from userspace.  If provided, use a stub
 353            already in userspace.  */
 354         if (ka->sa.sa_flags & SA_RESTORER) {
 355                 regs->pr = (unsigned long) ka->sa.sa_restorer;
 356 #ifdef CONFIG_VSYSCALL
 357         } else if (likely(current->mm->context.vdso)) {
 358                 regs->pr = VDSO_SYM(&__kernel_sigreturn);
 359 #endif
 360         } else {
 361                 /* Generate return code (system call to sigreturn) */
 362                 err |= __put_user(MOVW(7), &frame->retcode[0]);
 363                 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
 364                 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
 365                 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
 366                 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
 367                 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
 368                 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
 369                 err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
 370                 regs->pr = (unsigned long) frame->retcode;
 371         }
 372
 373         if (err)
 374                 goto give_sigsegv;
 375
 376         /* Set up registers for signal handler */
 377         regs->regs[15] = (unsigned long) frame;
 378         regs->regs[4] = signal; /* Arg for signal handler */
 379         regs->regs[5] = 0;
 380         regs->regs[6] = (unsigned long) &frame->sc;
 381         regs->pc = (unsigned long) ka->sa.sa_handler;
 382
 383         set_fs(USER_DS);
 384
 385         pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
 386                  current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
 387
 388         flush_cache_sigtramp(regs->pr);
 389
 390         if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
 391                 flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
 392
 393         return 0;
 394
 395 give_sigsegv:
 396         force_sigsegv(sig, current);
 397         return -EFAULT;
 398 }
 399
 400 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 401                            sigset_t *set, struct pt_regs *regs)
 402 {
 403         struct rt_sigframe __user *frame;
 404         int err = 0;
 405         int signal;
 406
 407         frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
 408
 409         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 410                 goto give_sigsegv;
 411
 412         signal = current_thread_info()->exec_domain
 413                 && current_thread_info()->exec_domain->signal_invmap
 414                 && sig < 32
 415                 ? current_thread_info()->exec_domain->signal_invmap[sig]
 416                 : sig;
 417
 418         err |= copy_siginfo_to_user(&frame->info, info);
 419
 420         /* Create the ucontext.  */
 421         err |= __put_user(0, &frame->uc.uc_flags);
 422         err |= __put_user(0, &frame->uc.uc_link);
 423         err |= __put_user((void *)current->sas_ss_sp,
 424                           &frame->uc.uc_stack.ss_sp);
 425         err |= __put_user(sas_ss_flags(regs->regs[15]),
 426                           &frame->uc.uc_stack.ss_flags);
 427         err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
 428         err |= setup_sigcontext(&frame->uc.uc_mcontext,
 429                                 regs, set->sig[0]);
 430         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 431
 432         /* Set up to return from userspace.  If provided, use a stub
 433            already in userspace.  */
 434         if (ka->sa.sa_flags & SA_RESTORER) {
 435                 regs->pr = (unsigned long) ka->sa.sa_restorer;
 436 #ifdef CONFIG_VSYSCALL
 437         } else if (likely(current->mm->context.vdso)) {
 438                 regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
 439 #endif
 440         } else {
 441                 /* Generate return code (system call to rt_sigreturn) */
 442                 err |= __put_user(MOVW(7), &frame->retcode[0]);
 443                 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
 444                 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
 445                 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
 446                 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
 447                 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
 448                 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
 449                 err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
 450                 regs->pr = (unsigned long) frame->retcode;
 451         }
 452
 453         if (err)
 454                 goto give_sigsegv;
 455
 456         /* Set up registers for signal handler */
 457         regs->regs[15] = (unsigned long) frame;
 458         regs->regs[4] = signal; /* Arg for signal handler */
 459         regs->regs[5] = (unsigned long) &frame->info;
 460         regs->regs[6] = (unsigned long) &frame->uc;
 461         regs->pc = (unsigned long) ka->sa.sa_handler;
 462
 463         set_fs(USER_DS);
 464
 465         pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
 466                  current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
 467
 468         flush_cache_sigtramp(regs->pr);
 469
 470         if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
 471                 flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
 472
 473         return 0;
 474
 475 give_sigsegv:
 476         force_sigsegv(sig, current);
 477         return -EFAULT;
 478 }
 479
 480 /*
 481  * OK, we're invoking a handler
 482  */
 483
 484 static int
 485 handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
 486               sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
 487 {
 488         int ret;
 489
 490         /* Are we from a system call? */
 491         if (regs->tra >= 0) {
 492                 /* If so, check system call restarting.. */
 493                 switch (regs->regs[0]) {
 494                         case -ERESTART_RESTARTBLOCK:
 495                         case -ERESTARTNOHAND:
 496                                 regs->regs[0] = -EINTR;
 497                                 break;
 498
 499                         case -ERESTARTSYS:
 500                                 if (!(ka->sa.sa_flags & SA_RESTART)) {
 501                                         regs->regs[0] = -EINTR;
 502                                         break;
 503                                 }
 504                         /* fallthrough */
 505                         case -ERESTARTNOINTR:
 506                                 regs->regs[0] = save_r0;
 507                                 regs->pc -= instruction_size(
 508                                                 ctrl_inw(regs->pc - 4));
 509                                 break;
 510                 }
 511         }
 512
 513         /* Set up the stack frame */
 514         if (ka->sa.sa_flags & SA_SIGINFO)
 515                 ret = setup_rt_frame(sig, ka, info, oldset, regs);
 516         else
 517                 ret = setup_frame(sig, ka, oldset, regs);
 518
 519         if (ka->sa.sa_flags & SA_ONESHOT)
 520                 ka->sa.sa_handler = SIG_DFL;
 521
 522         if (ret == 0) {
 523                 spin_lock_irq(&current->sighand->siglock);
 524                 sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
 525                 if (!(ka->sa.sa_flags & SA_NODEFER))
 526                         sigaddset(&current->blocked,sig);
 527                 recalc_sigpending();
 528                 spin_unlock_irq(&current->sighand->siglock);
 529         }
 530
 531         return ret;
 532 }
 533
 534 /*
 535  * Note that 'init' is a special process: it doesn't get signals it doesn't
 536  * want to handle. Thus you cannot kill init even with a SIGKILL even by
 537  * mistake.
 538  *
 539  * Note that we go through the signals twice: once to check the signals that
 540  * the kernel can handle, and then we build all the user-level signal handling
 541  * stack-frames in one go after that.
 542  */
 543 static void do_signal(struct pt_regs *regs, unsigned int save_r0)
 544 {
 545         siginfo_t info;
 546         int signr;
 547         struct k_sigaction ka;
 548         sigset_t *oldset;
 549
 550         /*
 551          * We want the common case to go fast, which
 552          * is why we may in certain cases get here from
 553          * kernel mode. Just return without doing anything
 554          * if so.
 555          */
 556         if (!user_mode(regs))
 557                 return;
 558
 559         if (try_to_freeze())
 560                 goto no_signal;
 561
 562         if (test_thread_flag(TIF_RESTORE_SIGMASK))
 563                 oldset = &current->saved_sigmask;
 564         else
 565                 oldset = &current->blocked;
 566
 567         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 568         if (signr > 0) {
 569                 /* Whee!  Actually deliver the signal.  */
 570                 if (handle_signal(signr, &ka, &info, oldset,
 571                                   regs, save_r0) == 0) {
 572                         /* a signal was successfully delivered; the saved
 573                          * sigmask will have been stored in the signal frame,
 574                          * and will be restored by sigreturn, so we can simply
 575                          * clear the TIF_RESTORE_SIGMASK flag */
 576                         if (test_thread_flag(TIF_RESTORE_SIGMASK))
 577                                 clear_thread_flag(TIF_RESTORE_SIGMASK);
 578                 }
 579
 580                 return;
 581         }
 582
 583  no_signal:
 584         /* Did we come from a system call? */
 585         if (regs->tra >= 0) {
 586                 /* Restart the system call - no handlers present */
 587                 if (regs->regs[0] == -ERESTARTNOHAND ||
 588                     regs->regs[0] == -ERESTARTSYS ||
 589                     regs->regs[0] == -ERESTARTNOINTR) {
 590                         regs->regs[0] = save_r0;
 591                         regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
 592                 } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
 593                         regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
 594                         regs->regs[3] = __NR_restart_syscall;
 595                 }
 596         }
 597
 598         /* if there's no signal to deliver, we just put the saved sigmask
 599          * back */
 600         if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
 601                 clear_thread_flag(TIF_RESTORE_SIGMASK);
 602                 sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
 603         }
 604 }
 605
 606 asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
 607                                  __u32 thread_info_flags)
 608 {
 609         /* deal with pending signal delivery */
 610         if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
 611                 do_signal(regs, save_r0);
 612 }