LXR linux/arch/sparc/kernel/signal

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  arch/sparc64/kernel/signal.c
   4 *
   5 *  Copyright (C) 1991, 1992  Linus Torvalds
   6 *  Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
   7 *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   8 *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
   9 *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
  10 */
  11
  12#include <linux/sched.h>
  13#include <linux/kernel.h>
  14#include <linux/signal.h>
  15#include <linux/errno.h>
  16#include <linux/wait.h>
  17#include <linux/ptrace.h>
  18#include <linux/tracehook.h>
  19#include <linux/unistd.h>
  20#include <linux/mm.h>
  21#include <linux/tty.h>
  22#include <linux/binfmts.h>
  23#include <linux/bitops.h>
  24#include <linux/context_tracking.h>
  25
  26#include <linux/uaccess.h>
  27#include <asm/ptrace.h>
  28#include <asm/pgtable.h>
  29#include <asm/fpumacro.h>
  30#include <asm/uctx.h>
  31#include <asm/siginfo.h>
  32#include <asm/visasm.h>
  33#include <asm/switch_to.h>
  34#include <asm/cacheflush.h>
  35
  36#include "sigutil.h"
  37#include "systbls.h"
  38#include "kernel.h"
  39#include "entry.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        enum ctx_state prev_state = exception_enter();
  47        mc_gregset_t __user *grp;
  48        unsigned long pc, npc, tstate;
  49        unsigned long fp, i7;
  50        unsigned char fenab;
  51        int err;
  52
  53        synchronize_user_stack();
  54        if (get_thread_wsaved()                                 ||
  55            (((unsigned long)ucp) & (sizeof(unsigned long)-1))  ||
  56            (!__access_ok(ucp, sizeof(*ucp))))
  57                goto do_sigsegv;
  58        grp  = &ucp->uc_mcontext.mc_gregs;
  59        err  = __get_user(pc, &((*grp)[MC_PC]));
  60        err |= __get_user(npc, &((*grp)[MC_NPC]));
  61        if (err || ((pc | npc) & 3))
  62                goto do_sigsegv;
  63        if (regs->u_regs[UREG_I1]) {
  64                sigset_t set;
  65
  66                if (_NSIG_WORDS == 1) {
  67                        if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
  68                                goto do_sigsegv;
  69                } else {
  70                        if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
  71                                goto do_sigsegv;
  72                }
  73                set_current_blocked(&set);
  74        }
  75        if (test_thread_flag(TIF_32BIT)) {
  76                pc &= 0xffffffff;
  77                npc &= 0xffffffff;
  78        }
  79        regs->tpc = pc;
  80        regs->tnpc = npc;
  81        err |= __get_user(regs->y, &((*grp)[MC_Y]));
  82        err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
  83        regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  84        regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  85        err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
  86        err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
  87        err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
  88        err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
  89        err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
  90        err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
  91
  92        /* Skip %g7 as that's the thread register in userspace.  */
  93
  94        err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
  95        err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
  96        err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
  97        err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
  98        err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
  99        err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
 100        err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
 101        err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
 102
 103        err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
 104        err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
 105        err |= __put_user(fp,
 106              (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
 107        err |= __put_user(i7,
 108              (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
 109
 110        err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
 111        if (fenab) {
 112                unsigned long *fpregs = current_thread_info()->fpregs;
 113                unsigned long fprs;
 114                
 115                fprs_write(0);
 116                err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
 117                if (fprs & FPRS_DL)
 118                        err |= copy_from_user(fpregs,
 119                                              &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
 120                                              (sizeof(unsigned int) * 32));
 121                if (fprs & FPRS_DU)
 122                        err |= copy_from_user(fpregs+16,
 123                         ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
 124                         (sizeof(unsigned int) * 32));
 125                err |= __get_user(current_thread_info()->xfsr[0],
 126                                  &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
 127                err |= __get_user(current_thread_info()->gsr[0],
 128                                  &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
 129                regs->tstate &= ~TSTATE_PEF;
 130        }
 131        if (err)
 132                goto do_sigsegv;
 133out:
 134        exception_exit(prev_state);
 135        return;
 136do_sigsegv:
 137        force_sig(SIGSEGV);
 138        goto out;
 139}
 140
 141asmlinkage void sparc64_get_context(struct pt_regs *regs)
 142{
 143        struct ucontext __user *ucp = (struct ucontext __user *)
 144                regs->u_regs[UREG_I0];
 145        enum ctx_state prev_state = exception_enter();
 146        mc_gregset_t __user *grp;
 147        mcontext_t __user *mcp;
 148        unsigned long fp, i7;
 149        unsigned char fenab;
 150        int err;
 151
 152        synchronize_user_stack();
 153        if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
 154                goto do_sigsegv;
 155
 156#if 1
 157        fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
 158#else
 159        fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
 160#endif
 161                
 162        mcp = &ucp->uc_mcontext;
 163        grp = &mcp->mc_gregs;
 164
 165        /* Skip over the trap instruction, first. */
 166        if (test_thread_flag(TIF_32BIT)) {
 167                regs->tpc   = (regs->tnpc & 0xffffffff);
 168                regs->tnpc  = (regs->tnpc + 4) & 0xffffffff;
 169        } else {
 170                regs->tpc   = regs->tnpc;
 171                regs->tnpc += 4;
 172        }
 173        err = 0;
 174        if (_NSIG_WORDS == 1)
 175                err |= __put_user(current->blocked.sig[0],
 176                                  (unsigned long __user *)&ucp->uc_sigmask);
 177        else
 178                err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
 179                                      sizeof(sigset_t));
 180
 181        err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
 182        err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
 183        err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
 184        err |= __put_user(regs->y, &((*grp)[MC_Y]));
 185        err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
 186        err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
 187        err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
 188        err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
 189        err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
 190        err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
 191        err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
 192        err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
 193        err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
 194        err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
 195        err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
 196        err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
 197        err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
 198        err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
 199        err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
 200
 201        err |= __get_user(fp,
 202                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
 203        err |= __get_user(i7,
 204                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
 205        err |= __put_user(fp, &(mcp->mc_fp));
 206        err |= __put_user(i7, &(mcp->mc_i7));
 207
 208        err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
 209        if (fenab) {
 210                unsigned long *fpregs = current_thread_info()->fpregs;
 211                unsigned long fprs;
 212                
 213                fprs = current_thread_info()->fpsaved[0];
 214                if (fprs & FPRS_DL)
 215                        err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
 216                                            (sizeof(unsigned int) * 32));
 217                if (fprs & FPRS_DU)
 218                        err |= copy_to_user(
 219                          ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
 220                          (sizeof(unsigned int) * 32));
 221                err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
 222                err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
 223                err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
 224        }
 225        if (err)
 226                goto do_sigsegv;
 227out:
 228        exception_exit(prev_state);
 229        return;
 230do_sigsegv:
 231        force_sig(SIGSEGV);
 232        goto out;
 233}
 234
 235/* Checks if the fp is valid.  We always build rt signal frames which
 236 * are 16-byte aligned, therefore we can always enforce that the
 237 * restore frame has that property as well.
 238 */
 239static bool invalid_frame_pointer(void __user *fp)
 240{
 241        if (((unsigned long) fp) & 15)
 242                return true;
 243        return false;
 244}
 245
 246struct rt_signal_frame {
 247        struct sparc_stackf     ss;
 248        siginfo_t               info;
 249        struct pt_regs          regs;
 250        __siginfo_fpu_t __user  *fpu_save;
 251        stack_t                 stack;
 252        sigset_t                mask;
 253        __siginfo_rwin_t        *rwin_save;
 254};
 255
 256void do_rt_sigreturn(struct pt_regs *regs)
 257{
 258        unsigned long tpc, tnpc, tstate, ufp;
 259        struct rt_signal_frame __user *sf;
 260        __siginfo_fpu_t __user *fpu_save;
 261        __siginfo_rwin_t __user *rwin_save;
 262        sigset_t set;
 263        int err;
 264
 265        /* Always make any pending restarted system calls return -EINTR */
 266        current->restart_block.fn = do_no_restart_syscall;
 267
 268        synchronize_user_stack ();
 269        sf = (struct rt_signal_frame __user *)
 270                (regs->u_regs [UREG_FP] + STACK_BIAS);
 271
 272        /* 1. Make sure we are not getting garbage from the user */
 273        if (invalid_frame_pointer(sf))
 274                goto segv;
 275
 276        if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
 277                goto segv;
 278
 279        if ((ufp + STACK_BIAS) & 0x7)
 280                goto segv;
 281
 282        err = __get_user(tpc, &sf->regs.tpc);
 283        err |= __get_user(tnpc, &sf->regs.tnpc);
 284        if (test_thread_flag(TIF_32BIT)) {
 285                tpc &= 0xffffffff;
 286                tnpc &= 0xffffffff;
 287        }
 288        err |= ((tpc | tnpc) & 3);
 289
 290        /* 2. Restore the state */
 291        err |= __get_user(regs->y, &sf->regs.y);
 292        err |= __get_user(tstate, &sf->regs.tstate);
 293        err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
 294
 295        /* User can only change condition codes and %asi in %tstate. */
 296        regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
 297        regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
 298
 299        err |= __get_user(fpu_save, &sf->fpu_save);
 300        if (!err && fpu_save)
 301                err |= restore_fpu_state(regs, fpu_save);
 302
 303        err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
 304        err |= restore_altstack(&sf->stack);
 305        if (err)
 306                goto segv;
 307
 308        err |= __get_user(rwin_save, &sf->rwin_save);
 309        if (!err && rwin_save) {
 310                if (restore_rwin_state(rwin_save))
 311                        goto segv;
 312        }
 313
 314        regs->tpc = tpc;
 315        regs->tnpc = tnpc;
 316
 317        /* Prevent syscall restart.  */
 318        pt_regs_clear_syscall(regs);
 319
 320        set_current_blocked(&set);
 321        return;
 322segv:
 323        force_sig(SIGSEGV);
 324}
 325
 326static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 327{
 328        unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
 329
 330        /*
 331         * If we are on the alternate signal stack and would overflow it, don't.
 332         * Return an always-bogus address instead so we will die with SIGSEGV.
 333         */
 334        if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
 335                return (void __user *) -1L;
 336
 337        /* This is the X/Open sanctioned signal stack switching.  */
 338        sp = sigsp(sp, ksig) - framesize;
 339
 340        /* Always align the stack frame.  This handles two cases.  First,
 341         * sigaltstack need not be mindful of platform specific stack
 342         * alignment.  Second, if we took this signal because the stack
 343         * is not aligned properly, we'd like to take the signal cleanly
 344         * and report that.
 345         */
 346        sp &= ~15UL;
 347
 348        return (void __user *) sp;
 349}
 350
 351static inline int
 352setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 353{
 354        struct rt_signal_frame __user *sf;
 355        int wsaved, err, sf_size;
 356        void __user *tail;
 357
 358        /* 1. Make sure everything is clean */
 359        synchronize_user_stack();
 360        save_and_clear_fpu();
 361        
 362        wsaved = get_thread_wsaved();
 363
 364        sf_size = sizeof(struct rt_signal_frame);
 365        if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 366                sf_size += sizeof(__siginfo_fpu_t);
 367        if (wsaved)
 368                sf_size += sizeof(__siginfo_rwin_t);
 369        sf = (struct rt_signal_frame __user *)
 370                get_sigframe(ksig, regs, sf_size);
 371
 372        if (invalid_frame_pointer (sf)) {
 373                if (show_unhandled_signals)
 374                        pr_info("%s[%d] bad frame in setup_rt_frame: %016lx TPC %016lx O7 %016lx\n",
 375                                current->comm, current->pid, (unsigned long)sf,
 376                                regs->tpc, regs->u_regs[UREG_I7]);
 377                force_sigsegv(ksig->sig);
 378                return -EINVAL;
 379        }
 380
 381        tail = (sf + 1);
 382
 383        /* 2. Save the current process state */
 384        err = copy_to_user(&sf->regs, regs, sizeof (*regs));
 385
 386        if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
 387                __siginfo_fpu_t __user *fpu_save = tail;
 388                tail += sizeof(__siginfo_fpu_t);
 389                err |= save_fpu_state(regs, fpu_save);
 390                err |= __put_user((u64)fpu_save, &sf->fpu_save);
 391        } else {
 392                err |= __put_user(0, &sf->fpu_save);
 393        }
 394        if (wsaved) {
 395                __siginfo_rwin_t __user *rwin_save = tail;
 396                tail += sizeof(__siginfo_rwin_t);
 397                err |= save_rwin_state(wsaved, rwin_save);
 398                err |= __put_user((u64)rwin_save, &sf->rwin_save);
 399                set_thread_wsaved(0);
 400        } else {
 401                err |= __put_user(0, &sf->rwin_save);
 402        }
 403        
 404        /* Setup sigaltstack */
 405        err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 406
 407        err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
 408
 409        if (!wsaved) {
 410                err |= copy_in_user((u64 __user *)sf,
 411                                    (u64 __user *)(regs->u_regs[UREG_FP] +
 412                                                   STACK_BIAS),
 413                                    sizeof(struct reg_window));
 414        } else {
 415                struct reg_window *rp;
 416
 417                rp = &current_thread_info()->reg_window[wsaved - 1];
 418                err |= copy_to_user(sf, rp, sizeof(struct reg_window));
 419        }
 420        if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 421                err |= copy_siginfo_to_user(&sf->info, &ksig->info);
 422        else {
 423                err |= __put_user(ksig->sig, &sf->info.si_signo);
 424                err |= __put_user(SI_NOINFO, &sf->info.si_code);
 425        }
 426        if (err)
 427                return err;
 428        
 429        /* 3. signal handler back-trampoline and parameters */
 430        regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
 431        regs->u_regs[UREG_I0] = ksig->sig;
 432        regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 433
 434        /* The sigcontext is passed in this way because of how it
 435         * is defined in GLIBC's /usr/include/bits/sigcontext.h
 436         * for sparc64.  It includes the 128 bytes of siginfo_t.
 437         */
 438        regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 439
 440        /* 5. signal handler */
 441        regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 442        regs->tnpc = (regs->tpc + 4);
 443        if (test_thread_flag(TIF_32BIT)) {
 444                regs->tpc &= 0xffffffff;
 445                regs->tnpc &= 0xffffffff;
 446        }
 447        /* 4. return to kernel instructions */
 448        regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 449        return 0;
 450}
 451
 452static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
 453                                   struct sigaction *sa)
 454{
 455        switch (regs->u_regs[UREG_I0]) {
 456        case ERESTART_RESTARTBLOCK:
 457        case ERESTARTNOHAND:
 458        no_system_call_restart:
 459                regs->u_regs[UREG_I0] = EINTR;
 460                regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
 461                break;
 462        case ERESTARTSYS:
 463                if (!(sa->sa_flags & SA_RESTART))
 464                        goto no_system_call_restart;
 465                /* fallthrough */
 466        case ERESTARTNOINTR:
 467                regs->u_regs[UREG_I0] = orig_i0;
 468                regs->tpc -= 4;
 469                regs->tnpc -= 4;
 470        }
 471}
 472
 473/* Note that 'init' is a special process: it doesn't get signals it doesn't
 474 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 475 * mistake.
 476 */
 477static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 478{
 479        struct ksignal ksig;
 480        int restart_syscall;
 481        bool has_handler;
 482        
 483        /* It's a lot of work and synchronization to add a new ptrace
 484         * register for GDB to save and restore in order to get
 485         * orig_i0 correct for syscall restarts when debugging.
 486         *
 487         * Although it should be the case that most of the global
 488         * registers are volatile across a system call, glibc already
 489         * depends upon that fact that we preserve them.  So we can't
 490         * just use any global register to save away the orig_i0 value.
 491         *
 492         * In particular %g2, %g3, %g4, and %g5 are all assumed to be
 493         * preserved across a system call trap by various pieces of
 494         * code in glibc.
 495         *
 496         * %g7 is used as the "thread register".   %g6 is not used in
 497         * any fixed manner.  %g6 is used as a scratch register and
 498         * a compiler temporary, but it's value is never used across
 499         * a system call.  Therefore %g6 is usable for orig_i0 storage.
 500         */
 501        if (pt_regs_is_syscall(regs) &&
 502            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
 503                regs->u_regs[UREG_G6] = orig_i0;
 504
 505#ifdef CONFIG_COMPAT
 506        if (test_thread_flag(TIF_32BIT)) {
 507                do_signal32(regs);
 508                return;
 509        }
 510#endif  
 511
 512        has_handler = get_signal(&ksig);
 513
 514        restart_syscall = 0;
 515        if (pt_regs_is_syscall(regs) &&
 516            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
 517                restart_syscall = 1;
 518                orig_i0 = regs->u_regs[UREG_G6];
 519        }
 520
 521        if (has_handler) {
 522                if (restart_syscall)
 523                        syscall_restart(orig_i0, regs, &ksig.ka.sa);
 524                signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
 525        } else {
 526                if (restart_syscall) {
 527                        switch (regs->u_regs[UREG_I0]) {
 528                        case ERESTARTNOHAND:
 529                        case ERESTARTSYS:
 530                        case ERESTARTNOINTR:
 531                                /* replay the system call when we are done */
 532                                regs->u_regs[UREG_I0] = orig_i0;
 533                                regs->tpc -= 4;
 534                                regs->tnpc -= 4;
 535                                pt_regs_clear_syscall(regs);
 536                                /* fall through */
 537                        case ERESTART_RESTARTBLOCK:
 538                                regs->u_regs[UREG_G1] = __NR_restart_syscall;
 539                                regs->tpc -= 4;
 540                                regs->tnpc -= 4;
 541                                pt_regs_clear_syscall(regs);
 542                        }
 543                }
 544                restore_saved_sigmask();
 545        }
 546}
 547
 548void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
 549{
 550        user_exit();
 551        if (thread_info_flags & _TIF_UPROBE)
 552                uprobe_notify_resume(regs);
 553        if (thread_info_flags & _TIF_SIGPENDING)
 554                do_signal(regs, orig_i0);
 555        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 556                clear_thread_flag(TIF_NOTIFY_RESUME);
 557                tracehook_notify_resume(regs);
 558        }
 559        user_enter();
 560}
 561
 562