arch/sparc/kernel/signal_64.c

   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. */
  41 asmlinkage 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;
 132 out:
 133         exception_exit(prev_state);
 134         return;
 135 do_sigsegv:
 136         force_sig(SIGSEGV);
 137         goto out;
 138 }
 139
 140 asmlinkage 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;
 226 out:
 227         exception_exit(prev_state);
 228         return;
 229 do_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  */
 238 static bool invalid_frame_pointer(void __user *fp)
 239 {
 240         if (((unsigned long) fp) & 15)
 241                 return true;
 242         return false;
 243 }
 244
 245 struct 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
 255 void 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;
 321 segv:
 322         force_sig(SIGSEGV);
 323 }
 324
 325 static 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
 350 static inline int
 351 setup_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
 451 static 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  */
 476 static 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
 547 void 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 /*
 560  * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
 561  * changes likely come with new fields that should be added below.
 562  */
 563 static_assert(NSIGILL   == 11);
 564 static_assert(NSIGFPE   == 15);
 565 static_assert(NSIGSEGV  == 9);
 566 static_assert(NSIGBUS   == 5);
 567 static_assert(NSIGTRAP  == 6);
 568 static_assert(NSIGCHLD  == 6);
 569 static_assert(NSIGSYS   == 2);
 570 static_assert(sizeof(siginfo_t) == 128);
 571 static_assert(__alignof__(siginfo_t) == 8);
 572 static_assert(offsetof(siginfo_t, si_signo)     == 0x00);
 573 static_assert(offsetof(siginfo_t, si_errno)     == 0x04);
 574 static_assert(offsetof(siginfo_t, si_code)      == 0x08);
 575 static_assert(offsetof(siginfo_t, si_pid)       == 0x10);
 576 static_assert(offsetof(siginfo_t, si_uid)       == 0x14);
 577 static_assert(offsetof(siginfo_t, si_tid)       == 0x10);
 578 static_assert(offsetof(siginfo_t, si_overrun)   == 0x14);
 579 static_assert(offsetof(siginfo_t, si_status)    == 0x18);
 580 static_assert(offsetof(siginfo_t, si_utime)     == 0x20);
 581 static_assert(offsetof(siginfo_t, si_stime)     == 0x28);
 582 static_assert(offsetof(siginfo_t, si_value)     == 0x18);
 583 static_assert(offsetof(siginfo_t, si_int)       == 0x18);
 584 static_assert(offsetof(siginfo_t, si_ptr)       == 0x18);
 585 static_assert(offsetof(siginfo_t, si_addr)      == 0x10);
 586 static_assert(offsetof(siginfo_t, si_trapno)    == 0x18);
 587 static_assert(offsetof(siginfo_t, si_addr_lsb)  == 0x18);
 588 static_assert(offsetof(siginfo_t, si_lower)     == 0x20);
 589 static_assert(offsetof(siginfo_t, si_upper)     == 0x28);
 590 static_assert(offsetof(siginfo_t, si_pkey)      == 0x20);
 591 static_assert(offsetof(siginfo_t, si_perf_data) == 0x18);
 592 static_assert(offsetof(siginfo_t, si_perf_type) == 0x20);
 593 static_assert(offsetof(siginfo_t, si_band)      == 0x10);
 594 static_assert(offsetof(siginfo_t, si_fd)        == 0x14);