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/fpumacro.h>
  29#include <asm/uctx.h>
  30#include <asm/siginfo.h>
  31#include <asm/visasm.h>
  32#include <asm/switch_to.h>
  33#include <asm/cacheflush.h>
  34
  35#include "sigutil.h"
  36#include "systbls.h"
  37#include "kernel.h"
  38#include "entry.h"
  39
  40/* {set, get}context() needed for 64-bit SparcLinux userland. */
  41asmlinkage void sparc64_set_context(struct pt_regs *regs)
  42{
  43        struct ucontext __user *ucp = (struct ucontext __user *)
  44                regs->u_regs[UREG_I0];
  45        enum ctx_state prev_state = exception_enter();
  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        synchronize_user_stack();
  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;
 132out:
 133        exception_exit(prev_state);
 134        return;
 135do_sigsegv:
 136        force_sig(SIGSEGV);
 137        goto out;
 138}
 139
 140asmlinkage void sparc64_get_context(struct pt_regs *regs)
 141{
 142        struct ucontext __user *ucp = (struct ucontext __user *)
 143                regs->u_regs[UREG_I0];
 144        enum ctx_state prev_state = exception_enter();
 145        mc_gregset_t __user *grp;
 146        mcontext_t __user *mcp;
 147        unsigned long fp, i7;
 148        unsigned char fenab;
 149        int err;
 150
 151        synchronize_user_stack();
 152        if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
 153                goto do_sigsegv;
 154
 155#if 1
 156        fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
 157#else
 158        fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
 159#endif
 160                
 161        mcp = &ucp->uc_mcontext;
 162        grp = &mcp->mc_gregs;
 163
 164        /* Skip over the trap instruction, first. */
 165        if (test_thread_flag(TIF_32BIT)) {
 166                regs->tpc   = (regs->tnpc & 0xffffffff);
 167                regs->tnpc  = (regs->tnpc + 4) & 0xffffffff;
 168        } else {
 169                regs->tpc   = regs->tnpc;
 170                regs->tnpc += 4;
 171        }
 172        err = 0;
 173        if (_NSIG_WORDS == 1)
 174                err |= __put_user(current->blocked.sig[0],
 175                                  (unsigned long __user *)&ucp->uc_sigmask);
 176        else
 177                err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
 178                                      sizeof(sigset_t));
 179
 180        err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
 181        err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
 182        err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
 183        err |= __put_user(regs->y, &((*grp)[MC_Y]));
 184        err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
 185        err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
 186        err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
 187        err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
 188        err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
 189        err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
 190        err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
 191        err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
 192        err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
 193        err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
 194        err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
 195        err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
 196        err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
 197        err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
 198        err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
 199
 200        err |= __get_user(fp,
 201                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
 202        err |= __get_user(i7,
 203                 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
 204        err |= __put_user(fp, &(mcp->mc_fp));
 205        err |= __put_user(i7, &(mcp->mc_i7));
 206
 207        err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
 208        if (fenab) {
 209                unsigned long *fpregs = current_thread_info()->fpregs;
 210                unsigned long fprs;
 211                
 212                fprs = current_thread_info()->fpsaved[0];
 213                if (fprs & FPRS_DL)
 214                        err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
 215                                            (sizeof(unsigned int) * 32));
 216                if (fprs & FPRS_DU)
 217                        err |= copy_to_user(
 218                          ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
 219                          (sizeof(unsigned int) * 32));
 220                err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
 221                err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
 222                err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
 223        }
 224        if (err)
 225                goto do_sigsegv;
 226out:
 227        exception_exit(prev_state);
 228        return;
 229do_sigsegv:
 230        force_sig(SIGSEGV);
 231        goto out;
 232}
 233
 234/* Checks if the fp is valid.  We always build rt signal frames which
 235 * are 16-byte aligned, therefore we can always enforce that the
 236 * restore frame has that property as well.
 237 */
 238static bool invalid_frame_pointer(void __user *fp)
 239{
 240        if (((unsigned long) fp) & 15)
 241                return true;
 242        return false;
 243}
 244
 245struct rt_signal_frame {
 246        struct sparc_stackf     ss;
 247        siginfo_t               info;
 248        struct pt_regs          regs;
 249        __siginfo_fpu_t __user  *fpu_save;
 250        stack_t                 stack;
 251        sigset_t                mask;
 252        __siginfo_rwin_t        *rwin_save;
 253};
 254
 255void do_rt_sigreturn(struct pt_regs *regs)
 256{
 257        unsigned long tpc, tnpc, tstate, ufp;
 258        struct rt_signal_frame __user *sf;
 259        __siginfo_fpu_t __user *fpu_save;
 260        __siginfo_rwin_t __user *rwin_save;
 261        sigset_t set;
 262        int err;
 263
 264        /* Always make any pending restarted system calls return -EINTR */
 265        current->restart_block.fn = do_no_restart_syscall;
 266
 267        synchronize_user_stack ();
 268        sf = (struct rt_signal_frame __user *)
 269                (regs->u_regs [UREG_FP] + STACK_BIAS);
 270
 271        /* 1. Make sure we are not getting garbage from the user */
 272        if (invalid_frame_pointer(sf))
 273                goto segv;
 274
 275        if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
 276                goto segv;
 277
 278        if ((ufp + STACK_BIAS) & 0x7)
 279                goto segv;
 280
 281        err = __get_user(tpc, &sf->regs.tpc);
 282        err |= __get_user(tnpc, &sf->regs.tnpc);
 283        if (test_thread_flag(TIF_32BIT)) {
 284                tpc &= 0xffffffff;
 285                tnpc &= 0xffffffff;
 286        }
 287        err |= ((tpc | tnpc) & 3);
 288
 289        /* 2. Restore the state */
 290        err |= __get_user(regs->y, &sf->regs.y);
 291        err |= __get_user(tstate, &sf->regs.tstate);
 292        err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
 293
 294        /* User can only change condition codes and %asi in %tstate. */
 295        regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
 296        regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
 297
 298        err |= __get_user(fpu_save, &sf->fpu_save);
 299        if (!err && fpu_save)
 300                err |= restore_fpu_state(regs, fpu_save);
 301
 302        err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
 303        err |= restore_altstack(&sf->stack);
 304        if (err)
 305                goto segv;
 306
 307        err |= __get_user(rwin_save, &sf->rwin_save);
 308        if (!err && rwin_save) {
 309                if (restore_rwin_state(rwin_save))
 310                        goto segv;
 311        }
 312
 313        regs->tpc = tpc;
 314        regs->tnpc = tnpc;
 315
 316        /* Prevent syscall restart.  */
 317        pt_regs_clear_syscall(regs);
 318
 319        set_current_blocked(&set);
 320        return;
 321segv:
 322        force_sig(SIGSEGV);
 323}
 324
 325static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 326{
 327        unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
 328
 329        /*
 330         * If we are on the alternate signal stack and would overflow it, don't.
 331         * Return an always-bogus address instead so we will die with SIGSEGV.
 332         */
 333        if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
 334                return (void __user *) -1L;
 335
 336        /* This is the X/Open sanctioned signal stack switching.  */
 337        sp = sigsp(sp, ksig) - framesize;
 338
 339        /* Always align the stack frame.  This handles two cases.  First,
 340         * sigaltstack need not be mindful of platform specific stack
 341         * alignment.  Second, if we took this signal because the stack
 342         * is not aligned properly, we'd like to take the signal cleanly
 343         * and report that.
 344         */
 345        sp &= ~15UL;
 346
 347        return (void __user *) sp;
 348}
 349
 350static inline int
 351setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 352{
 353        struct rt_signal_frame __user *sf;
 354        int wsaved, err, sf_size;
 355        void __user *tail;
 356
 357        /* 1. Make sure everything is clean */
 358        synchronize_user_stack();
 359        save_and_clear_fpu();
 360        
 361        wsaved = get_thread_wsaved();
 362
 363        sf_size = sizeof(struct rt_signal_frame);
 364        if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 365                sf_size += sizeof(__siginfo_fpu_t);
 366        if (wsaved)
 367                sf_size += sizeof(__siginfo_rwin_t);
 368        sf = (struct rt_signal_frame __user *)
 369                get_sigframe(ksig, regs, sf_size);
 370
 371        if (invalid_frame_pointer (sf)) {
 372                if (show_unhandled_signals)
 373                        pr_info("%s[%d] bad frame in setup_rt_frame: %016lx TPC %016lx O7 %016lx\n",
 374                                current->comm, current->pid, (unsigned long)sf,
 375                                regs->tpc, regs->u_regs[UREG_I7]);
 376                force_sigsegv(ksig->sig);
 377                return -EINVAL;
 378        }
 379
 380        tail = (sf + 1);
 381
 382        /* 2. Save the current process state */
 383        err = copy_to_user(&sf->regs, regs, sizeof (*regs));
 384
 385        if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
 386                __siginfo_fpu_t __user *fpu_save = tail;
 387                tail += sizeof(__siginfo_fpu_t);
 388                err |= save_fpu_state(regs, fpu_save);
 389                err |= __put_user((u64)fpu_save, &sf->fpu_save);
 390        } else {
 391                err |= __put_user(0, &sf->fpu_save);
 392        }
 393        if (wsaved) {
 394                __siginfo_rwin_t __user *rwin_save = tail;
 395                tail += sizeof(__siginfo_rwin_t);
 396                err |= save_rwin_state(wsaved, rwin_save);
 397                err |= __put_user((u64)rwin_save, &sf->rwin_save);
 398                set_thread_wsaved(0);
 399        } else {
 400                err |= __put_user(0, &sf->rwin_save);
 401        }
 402        
 403        /* Setup sigaltstack */
 404        err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 405
 406        err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
 407
 408        if (!wsaved) {
 409                err |= copy_in_user((u64 __user *)sf,
 410                                    (u64 __user *)(regs->u_regs[UREG_FP] +
 411                                                   STACK_BIAS),
 412                                    sizeof(struct reg_window));
 413        } else {
 414                struct reg_window *rp;
 415
 416                rp = &current_thread_info()->reg_window[wsaved - 1];
 417                err |= copy_to_user(sf, rp, sizeof(struct reg_window));
 418        }
 419        if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 420                err |= copy_siginfo_to_user(&sf->info, &ksig->info);
 421        else {
 422                err |= __put_user(ksig->sig, &sf->info.si_signo);
 423                err |= __put_user(SI_NOINFO, &sf->info.si_code);
 424        }
 425        if (err)
 426                return err;
 427        
 428        /* 3. signal handler back-trampoline and parameters */
 429        regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
 430        regs->u_regs[UREG_I0] = ksig->sig;
 431        regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 432
 433        /* The sigcontext is passed in this way because of how it
 434         * is defined in GLIBC's /usr/include/bits/sigcontext.h
 435         * for sparc64.  It includes the 128 bytes of siginfo_t.
 436         */
 437        regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 438
 439        /* 5. signal handler */
 440        regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 441        regs->tnpc = (regs->tpc + 4);
 442        if (test_thread_flag(TIF_32BIT)) {
 443                regs->tpc &= 0xffffffff;
 444                regs->tnpc &= 0xffffffff;
 445        }
 446        /* 4. return to kernel instructions */
 447        regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 448        return 0;
 449}
 450
 451static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
 452                                   struct sigaction *sa)
 453{
 454        switch (regs->u_regs[UREG_I0]) {
 455        case ERESTART_RESTARTBLOCK:
 456        case ERESTARTNOHAND:
 457        no_system_call_restart:
 458                regs->u_regs[UREG_I0] = EINTR;
 459                regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
 460                break;
 461        case ERESTARTSYS:
 462                if (!(sa->sa_flags & SA_RESTART))
 463                        goto no_system_call_restart;
 464                fallthrough;
 465        case ERESTARTNOINTR:
 466                regs->u_regs[UREG_I0] = orig_i0;
 467                regs->tpc -= 4;
 468                regs->tnpc -= 4;
 469        }
 470}
 471
 472/* Note that 'init' is a special process: it doesn't get signals it doesn't
 473 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 474 * mistake.
 475 */
 476static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 477{
 478        struct ksignal ksig;
 479        int restart_syscall;
 480        bool has_handler;
 481        
 482        /* It's a lot of work and synchronization to add a new ptrace
 483         * register for GDB to save and restore in order to get
 484         * orig_i0 correct for syscall restarts when debugging.
 485         *
 486         * Although it should be the case that most of the global
 487         * registers are volatile across a system call, glibc already
 488         * depends upon that fact that we preserve them.  So we can't
 489         * just use any global register to save away the orig_i0 value.
 490         *
 491         * In particular %g2, %g3, %g4, and %g5 are all assumed to be
 492         * preserved across a system call trap by various pieces of
 493         * code in glibc.
 494         *
 495         * %g7 is used as the "thread register".   %g6 is not used in
 496         * any fixed manner.  %g6 is used as a scratch register and
 497         * a compiler temporary, but it's value is never used across
 498         * a system call.  Therefore %g6 is usable for orig_i0 storage.
 499         */
 500        if (pt_regs_is_syscall(regs) &&
 501            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
 502                regs->u_regs[UREG_G6] = orig_i0;
 503
 504#ifdef CONFIG_COMPAT
 505        if (test_thread_flag(TIF_32BIT)) {
 506                do_signal32(regs);
 507                return;
 508        }
 509#endif  
 510
 511        has_handler = get_signal(&ksig);
 512
 513        restart_syscall = 0;
 514        if (pt_regs_is_syscall(regs) &&
 515            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
 516                restart_syscall = 1;
 517                orig_i0 = regs->u_regs[UREG_G6];
 518        }
 519
 520        if (has_handler) {
 521                if (restart_syscall)
 522                        syscall_restart(orig_i0, regs, &ksig.ka.sa);
 523                signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
 524        } else {
 525                if (restart_syscall) {
 526                        switch (regs->u_regs[UREG_I0]) {
 527                        case ERESTARTNOHAND:
 528                        case ERESTARTSYS:
 529                        case ERESTARTNOINTR:
 530                                /* replay the system call when we are done */
 531                                regs->u_regs[UREG_I0] = orig_i0;
 532                                regs->tpc -= 4;
 533                                regs->tnpc -= 4;
 534                                pt_regs_clear_syscall(regs);
 535                                fallthrough;
 536                        case ERESTART_RESTARTBLOCK:
 537                                regs->u_regs[UREG_G1] = __NR_restart_syscall;
 538                                regs->tpc -= 4;
 539                                regs->tnpc -= 4;
 540                                pt_regs_clear_syscall(regs);
 541                        }
 542                }
 543                restore_saved_sigmask();
 544        }
 545}
 546
 547void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
 548{
 549        user_exit();
 550        if (thread_info_flags & _TIF_UPROBE)
 551                uprobe_notify_resume(regs);
 552        if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
 553                do_signal(regs, orig_i0);
 554        if (thread_info_flags & _TIF_NOTIFY_RESUME)
 555                tracehook_notify_resume(regs);
 556        user_enter();
 557}
 558
 559