linux/arch/sparc/kernel/signal_64.c
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   1/*
   2 *  arch/sparc64/kernel/signal.c
   3 *
   4 *  Copyright (C) 1991, 1992  Linus Torvalds
   5 *  Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
   6 *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   7 *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
   8 *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   9 */
  10
  11#ifdef CONFIG_COMPAT
  12#include <linux/compat.h>       /* for compat_old_sigset_t */
  13#endif
  14#include <linux/sched.h>
  15#include <linux/kernel.h>
  16#include <linux/signal.h>
  17#include <linux/errno.h>
  18#include <linux/wait.h>
  19#include <linux/ptrace.h>
  20#include <linux/tracehook.h>
  21#include <linux/unistd.h>
  22#include <linux/mm.h>
  23#include <linux/tty.h>
  24#include <linux/binfmts.h>
  25#include <linux/bitops.h>
  26
  27#include <asm/uaccess.h>
  28#include <asm/ptrace.h>
  29#include <asm/pgtable.h>
  30#include <asm/fpumacro.h>
  31#include <asm/uctx.h>
  32#include <asm/siginfo.h>
  33#include <asm/visasm.h>
  34#include <asm/switch_to.h>
  35#include <asm/cacheflush.h>
  36
  37#include "entry.h"
  38#include "systbls.h"
  39#include "sigutil.h"
  40
  41/* {set, get}context() needed for 64-bit SparcLinux userland. */
  42asmlinkage void sparc64_set_context(struct pt_regs *regs)
  43{
  44        struct ucontext __user *ucp = (struct ucontext __user *)
  45                regs->u_regs[UREG_I0];
  46        mc_gregset_t __user *grp;
  47        unsigned long pc, npc, tstate;
  48        unsigned long fp, i7;
  49        unsigned char fenab;
  50        int err;
  51
  52        flush_user_windows();
  53        if (get_thread_wsaved()                                 ||
  54            (((unsigned long)ucp) & (sizeof(unsigned long)-1))  ||
  55            (!__access_ok(ucp, sizeof(*ucp))))
  56                goto do_sigsegv;
  57        grp  = &ucp->uc_mcontext.mc_gregs;
  58        err  = __get_user(pc, &((*grp)[MC_PC]));
  59        err |= __get_user(npc, &((*grp)[MC_NPC]));
  60        if (err || ((pc | npc) & 3))
  61                goto do_sigsegv;
  62        if (regs->u_regs[UREG_I1]) {
  63                sigset_t set;
  64
  65                if (_NSIG_WORDS == 1) {
  66                        if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
  67                                goto do_sigsegv;
  68                } else {
  69                        if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
  70                                goto do_sigsegv;
  71                }
  72                set_current_blocked(&set);
  73        }
  74        if (test_thread_flag(TIF_32BIT)) {
  75                pc &= 0xffffffff;
  76                npc &= 0xffffffff;
  77        }
  78        regs->tpc = pc;
  79        regs->tnpc = npc;
  80        err |= __get_user(regs->y, &((*grp)[MC_Y]));
  81        err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
  82        regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  83        regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  84        err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
  85        err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
  86        err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
  87        err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
  88        err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
  89        err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
  90
  91        /* Skip %g7 as that's the thread register in userspace.  */
  92
  93        err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
  94        err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
  95        err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
  96        err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
  97        err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
  98        err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
  99        err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
 100        err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
 101
 102        err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
 103        err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
 104        err |= __put_user(fp,
 105              (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
 106        err |= __put_user(i7,
 107              (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
 108
 109        err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
 110        if (fenab) {
 111                unsigned long *fpregs = current_thread_info()->fpregs;
 112                unsigned long fprs;
 113                
 114                fprs_write(0);
 115                err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
 116                if (fprs & FPRS_DL)
 117                        err |= copy_from_user(fpregs,
 118                                              &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
 119                                              (sizeof(unsigned int) * 32));
 120                if (fprs & FPRS_DU)
 121                        err |= copy_from_user(fpregs+16,
 122                         ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
 123                         (sizeof(unsigned int) * 32));
 124                err |= __get_user(current_thread_info()->xfsr[0],
 125                                  &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
 126                err |= __get_user(current_thread_info()->gsr[0],
 127                                  &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
 128                regs->tstate &= ~TSTATE_PEF;
 129        }
 130        if (err)
 131                goto do_sigsegv;
 132
 133        return;
 134do_sigsegv:
 135        force_sig(SIGSEGV, current);
 136}
 137
 138asmlinkage void sparc64_get_context(struct pt_regs *regs)
 139{
 140        struct ucontext __user *ucp = (struct ucontext __user *)
 141                regs->u_regs[UREG_I0];
 142        mc_gregset_t __user *grp;
 143        mcontext_t __user *mcp;
 144        unsigned long fp, i7;
 145        unsigned char fenab;
 146        int err;
 147
 148        synchronize_user_stack();
 149        if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
 150                goto do_sigsegv;
 151
 152#if 1
 153        fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
 154#else
 155        fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
 156#endif
 157                
 158        mcp = &ucp->uc_mcontext;
 159        grp = &mcp->mc_gregs;
 160
 161        /* Skip over the trap instruction, first. */
 162        if (test_thread_flag(TIF_32BIT)) {
 163                regs->tpc   = (regs->tnpc & 0xffffffff);
 164                regs->tnpc  = (regs->tnpc + 4) & 0xffffffff;
 165        } else {
 166                regs->tpc   = regs->tnpc;
 167                regs->tnpc += 4;
 168        }
 169        err = 0;
 170        if (_NSIG_WORDS == 1)
 171                err |= __put_user(current->blocked.sig[0],
 172                                  (unsigned long __user *)&ucp->uc_sigmask);
 173        else
 174                err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
 175                                      sizeof(sigset_t));
 176
 177        err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
 178        err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
 179        err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
 180        err |= __put_user(regs->y, &((*grp)[MC_Y]));
 181        err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
 182        err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
 183        err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
 184        err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
 185        err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
 186        err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
 187        err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
 188        err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
 189        err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
 190        err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
 191        err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
 192        err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
 193        err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
 194        err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
 195        err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
 196
 197        err |= __get_user(fp,
 198                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
 199        err |= __get_user(i7,
 200                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
 201        err |= __put_user(fp, &(mcp->mc_fp));
 202        err |= __put_user(i7, &(mcp->mc_i7));
 203
 204        err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
 205        if (fenab) {
 206                unsigned long *fpregs = current_thread_info()->fpregs;
 207                unsigned long fprs;
 208                
 209                fprs = current_thread_info()->fpsaved[0];
 210                if (fprs & FPRS_DL)
 211                        err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
 212                                            (sizeof(unsigned int) * 32));
 213                if (fprs & FPRS_DU)
 214                        err |= copy_to_user(
 215                          ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
 216                          (sizeof(unsigned int) * 32));
 217                err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
 218                err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
 219                err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
 220        }
 221        if (err)
 222                goto do_sigsegv;
 223
 224        return;
 225do_sigsegv:
 226        force_sig(SIGSEGV, current);
 227}
 228
 229struct rt_signal_frame {
 230        struct sparc_stackf     ss;
 231        siginfo_t               info;
 232        struct pt_regs          regs;
 233        __siginfo_fpu_t __user  *fpu_save;
 234        stack_t                 stack;
 235        sigset_t                mask;
 236        __siginfo_rwin_t        *rwin_save;
 237};
 238
 239void do_rt_sigreturn(struct pt_regs *regs)
 240{
 241        struct rt_signal_frame __user *sf;
 242        unsigned long tpc, tnpc, tstate;
 243        __siginfo_fpu_t __user *fpu_save;
 244        __siginfo_rwin_t __user *rwin_save;
 245        sigset_t set;
 246        int err;
 247
 248        /* Always make any pending restarted system calls return -EINTR */
 249        current_thread_info()->restart_block.fn = do_no_restart_syscall;
 250
 251        synchronize_user_stack ();
 252        sf = (struct rt_signal_frame __user *)
 253                (regs->u_regs [UREG_FP] + STACK_BIAS);
 254
 255        /* 1. Make sure we are not getting garbage from the user */
 256        if (((unsigned long) sf) & 3)
 257                goto segv;
 258
 259        err = get_user(tpc, &sf->regs.tpc);
 260        err |= __get_user(tnpc, &sf->regs.tnpc);
 261        if (test_thread_flag(TIF_32BIT)) {
 262                tpc &= 0xffffffff;
 263                tnpc &= 0xffffffff;
 264        }
 265        err |= ((tpc | tnpc) & 3);
 266
 267        /* 2. Restore the state */
 268        err |= __get_user(regs->y, &sf->regs.y);
 269        err |= __get_user(tstate, &sf->regs.tstate);
 270        err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
 271
 272        /* User can only change condition codes and %asi in %tstate. */
 273        regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
 274        regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
 275
 276        err |= __get_user(fpu_save, &sf->fpu_save);
 277        if (!err && fpu_save)
 278                err |= restore_fpu_state(regs, fpu_save);
 279
 280        err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
 281        err |= restore_altstack(&sf->stack);
 282        if (err)
 283                goto segv;
 284
 285        err |= __get_user(rwin_save, &sf->rwin_save);
 286        if (!err && rwin_save) {
 287                if (restore_rwin_state(rwin_save))
 288                        goto segv;
 289        }
 290
 291        regs->tpc = tpc;
 292        regs->tnpc = tnpc;
 293
 294        /* Prevent syscall restart.  */
 295        pt_regs_clear_syscall(regs);
 296
 297        set_current_blocked(&set);
 298        return;
 299segv:
 300        force_sig(SIGSEGV, current);
 301}
 302
 303/* Checks if the fp is valid */
 304static int invalid_frame_pointer(void __user *fp)
 305{
 306        if (((unsigned long) fp) & 15)
 307                return 1;
 308        return 0;
 309}
 310
 311static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 312{
 313        unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
 314
 315        /*
 316         * If we are on the alternate signal stack and would overflow it, don't.
 317         * Return an always-bogus address instead so we will die with SIGSEGV.
 318         */
 319        if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
 320                return (void __user *) -1L;
 321
 322        /* This is the X/Open sanctioned signal stack switching.  */
 323        sp = sigsp(sp, ksig) - framesize;
 324
 325        /* Always align the stack frame.  This handles two cases.  First,
 326         * sigaltstack need not be mindful of platform specific stack
 327         * alignment.  Second, if we took this signal because the stack
 328         * is not aligned properly, we'd like to take the signal cleanly
 329         * and report that.
 330         */
 331        sp &= ~15UL;
 332
 333        return (void __user *) sp;
 334}
 335
 336static inline int
 337setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 338{
 339        struct rt_signal_frame __user *sf;
 340        int wsaved, err, sf_size;
 341        void __user *tail;
 342
 343        /* 1. Make sure everything is clean */
 344        synchronize_user_stack();
 345        save_and_clear_fpu();
 346        
 347        wsaved = get_thread_wsaved();
 348
 349        sf_size = sizeof(struct rt_signal_frame);
 350        if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 351                sf_size += sizeof(__siginfo_fpu_t);
 352        if (wsaved)
 353                sf_size += sizeof(__siginfo_rwin_t);
 354        sf = (struct rt_signal_frame __user *)
 355                get_sigframe(ksig, regs, sf_size);
 356
 357        if (invalid_frame_pointer (sf)) {
 358                do_exit(SIGILL);        /* won't return, actually */
 359                return -EINVAL;
 360        }
 361
 362        tail = (sf + 1);
 363
 364        /* 2. Save the current process state */
 365        err = copy_to_user(&sf->regs, regs, sizeof (*regs));
 366
 367        if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
 368                __siginfo_fpu_t __user *fpu_save = tail;
 369                tail += sizeof(__siginfo_fpu_t);
 370                err |= save_fpu_state(regs, fpu_save);
 371                err |= __put_user((u64)fpu_save, &sf->fpu_save);
 372        } else {
 373                err |= __put_user(0, &sf->fpu_save);
 374        }
 375        if (wsaved) {
 376                __siginfo_rwin_t __user *rwin_save = tail;
 377                tail += sizeof(__siginfo_rwin_t);
 378                err |= save_rwin_state(wsaved, rwin_save);
 379                err |= __put_user((u64)rwin_save, &sf->rwin_save);
 380                set_thread_wsaved(0);
 381        } else {
 382                err |= __put_user(0, &sf->rwin_save);
 383        }
 384        
 385        /* Setup sigaltstack */
 386        err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 387
 388        err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
 389
 390        if (!wsaved) {
 391                err |= copy_in_user((u64 __user *)sf,
 392                                    (u64 __user *)(regs->u_regs[UREG_FP] +
 393                                                   STACK_BIAS),
 394                                    sizeof(struct reg_window));
 395        } else {
 396                struct reg_window *rp;
 397
 398                rp = &current_thread_info()->reg_window[wsaved - 1];
 399                err |= copy_to_user(sf, rp, sizeof(struct reg_window));
 400        }
 401        if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 402                err |= copy_siginfo_to_user(&sf->info, &ksig->info);
 403        else {
 404                err |= __put_user(ksig->sig, &sf->info.si_signo);
 405                err |= __put_user(SI_NOINFO, &sf->info.si_code);
 406        }
 407        if (err)
 408                return err;
 409        
 410        /* 3. signal handler back-trampoline and parameters */
 411        regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
 412        regs->u_regs[UREG_I0] = ksig->sig;
 413        regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 414
 415        /* The sigcontext is passed in this way because of how it
 416         * is defined in GLIBC's /usr/include/bits/sigcontext.h
 417         * for sparc64.  It includes the 128 bytes of siginfo_t.
 418         */
 419        regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 420
 421        /* 5. signal handler */
 422        regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 423        regs->tnpc = (regs->tpc + 4);
 424        if (test_thread_flag(TIF_32BIT)) {
 425                regs->tpc &= 0xffffffff;
 426                regs->tnpc &= 0xffffffff;
 427        }
 428        /* 4. return to kernel instructions */
 429        regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 430        return 0;
 431}
 432
 433static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
 434                                   struct sigaction *sa)
 435{
 436        switch (regs->u_regs[UREG_I0]) {
 437        case ERESTART_RESTARTBLOCK:
 438        case ERESTARTNOHAND:
 439        no_system_call_restart:
 440                regs->u_regs[UREG_I0] = EINTR;
 441                regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
 442                break;
 443        case ERESTARTSYS:
 444                if (!(sa->sa_flags & SA_RESTART))
 445                        goto no_system_call_restart;
 446                /* fallthrough */
 447        case ERESTARTNOINTR:
 448                regs->u_regs[UREG_I0] = orig_i0;
 449                regs->tpc -= 4;
 450                regs->tnpc -= 4;
 451        }
 452}
 453
 454/* Note that 'init' is a special process: it doesn't get signals it doesn't
 455 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 456 * mistake.
 457 */
 458static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 459{
 460        struct ksignal ksig;
 461        int restart_syscall;
 462        bool has_handler;
 463        
 464        /* It's a lot of work and synchronization to add a new ptrace
 465         * register for GDB to save and restore in order to get
 466         * orig_i0 correct for syscall restarts when debugging.
 467         *
 468         * Although it should be the case that most of the global
 469         * registers are volatile across a system call, glibc already
 470         * depends upon that fact that we preserve them.  So we can't
 471         * just use any global register to save away the orig_i0 value.
 472         *
 473         * In particular %g2, %g3, %g4, and %g5 are all assumed to be
 474         * preserved across a system call trap by various pieces of
 475         * code in glibc.
 476         *
 477         * %g7 is used as the "thread register".   %g6 is not used in
 478         * any fixed manner.  %g6 is used as a scratch register and
 479         * a compiler temporary, but it's value is never used across
 480         * a system call.  Therefore %g6 is usable for orig_i0 storage.
 481         */
 482        if (pt_regs_is_syscall(regs) &&
 483            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
 484                regs->u_regs[UREG_G6] = orig_i0;
 485
 486#ifdef CONFIG_COMPAT
 487        if (test_thread_flag(TIF_32BIT)) {
 488                extern void do_signal32(struct pt_regs *);
 489                do_signal32(regs);
 490                return;
 491        }
 492#endif  
 493
 494        has_handler = get_signal(&ksig);
 495
 496        restart_syscall = 0;
 497        if (pt_regs_is_syscall(regs) &&
 498            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
 499                restart_syscall = 1;
 500                orig_i0 = regs->u_regs[UREG_G6];
 501        }
 502
 503        if (has_handler) {
 504                if (restart_syscall)
 505                        syscall_restart(orig_i0, regs, &ksig.ka.sa);
 506                signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
 507        } else {
 508                if (restart_syscall) {
 509                        switch (regs->u_regs[UREG_I0]) {
 510                        case ERESTARTNOHAND:
 511                        case ERESTARTSYS:
 512                        case ERESTARTNOINTR:
 513                                /* replay the system call when we are done */
 514                                regs->u_regs[UREG_I0] = orig_i0;
 515                                regs->tpc -= 4;
 516                                regs->tnpc -= 4;
 517                                pt_regs_clear_syscall(regs);
 518                        case ERESTART_RESTARTBLOCK:
 519                                regs->u_regs[UREG_G1] = __NR_restart_syscall;
 520                                regs->tpc -= 4;
 521                                regs->tnpc -= 4;
 522                                pt_regs_clear_syscall(regs);
 523                        }
 524                }
 525                restore_saved_sigmask();
 526        }
 527}
 528
 529void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
 530{
 531        if (thread_info_flags & _TIF_SIGPENDING)
 532                do_signal(regs, orig_i0);
 533        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 534                clear_thread_flag(TIF_NOTIFY_RESUME);
 535                tracehook_notify_resume(regs);
 536        }
 537}
 538
 539