trap.c

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    1 /*-
    2  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
    3  * Copyright (C) 1995, 1996 TooLs GmbH.
    4  * All rights reserved.
    5  *
    6  * Redistribution and use in source and binary forms, with or without
    7  * modification, are permitted provided that the following conditions
    8  * are met:
    9  * 1. Redistributions of source code must retain the above copyright
   10  *    notice, this list of conditions and the following disclaimer.
   11  * 2. Redistributions in binary form must reproduce the above copyright
   12  *    notice, this list of conditions and the following disclaimer in the
   13  *    documentation and/or other materials provided with the distribution.
   14  * 3. All advertising materials mentioning features or use of this software
   15  *    must display the following acknowledgement:
   16  *      This product includes software developed by TooLs GmbH.
   17  * 4. The name of TooLs GmbH may not be used to endorse or promote products
   18  *    derived from this software without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
   21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   23  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
   26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   30  *
   31  * $NetBSD: trap.c,v 1.58 2002/03/04 04:07:35 dbj Exp $
   32  */
   33 
   34 #include <sys/cdefs.h>
   35 __FBSDID("$FreeBSD$");
   36 
   37 #include "opt_ktrace.h"
   38 
   39 #include <sys/param.h>
   40 #include <sys/kdb.h>
   41 #include <sys/proc.h>
   42 #include <sys/ktr.h>
   43 #include <sys/lock.h>
   44 #include <sys/mutex.h>
   45 #include <sys/pioctl.h>
   46 #include <sys/ptrace.h>
   47 #include <sys/reboot.h>
   48 #include <sys/syscall.h>
   49 #include <sys/sysent.h>
   50 #include <sys/systm.h>
   51 #include <sys/uio.h>
   52 #include <sys/signalvar.h>
   53 #ifdef KTRACE
   54 #include <sys/ktrace.h>
   55 #endif
   56 #include <sys/vmmeter.h>
   57 
   58 #include <security/audit/audit.h>
   59 
   60 #include <vm/vm.h>
   61 #include <vm/pmap.h>
   62 #include <vm/vm_extern.h>
   63 #include <vm/vm_param.h>
   64 #include <vm/vm_kern.h>
   65 #include <vm/vm_map.h>
   66 #include <vm/vm_page.h>
   67 
   68 #include <machine/cpu.h>
   69 #include <machine/db_machdep.h>
   70 #include <machine/fpu.h>
   71 #include <machine/frame.h>
   72 #include <machine/pcb.h>
   73 #include <machine/pmap.h>
   74 #include <machine/psl.h>
   75 #include <machine/trap.h>
   76 #include <machine/spr.h>
   77 #include <machine/sr.h>
   78 
   79 static void     trap_fatal(struct trapframe *frame);
   80 static void     printtrap(u_int vector, struct trapframe *frame, int isfatal,
   81                     int user);
   82 static int      trap_pfault(struct trapframe *frame, int user);
   83 static int      fix_unaligned(struct thread *td, struct trapframe *frame);
   84 static int      handle_onfault(struct trapframe *frame);
   85 static void     syscall(struct trapframe *frame);
   86 
   87 static __inline void    setusr(u_int);
   88 
   89 int     setfault(faultbuf);             /* defined in locore.S */
   90 
   91 /* Why are these not defined in a header? */
   92 int     badaddr(void *, size_t);
   93 int     badaddr_read(void *, size_t, int *);
   94 
   95 extern char     *syscallnames[];
   96 
   97 struct powerpc_exception {
   98         u_int   vector;
   99         char    *name;
  100 };
  101 
  102 static struct powerpc_exception powerpc_exceptions[] = {
  103         { 0x0100, "system reset" },
  104         { 0x0200, "machine check" },
  105         { 0x0300, "data storage interrupt" },
  106         { 0x0400, "instruction storage interrupt" },
  107         { 0x0500, "external interrupt" },
  108         { 0x0600, "alignment" },
  109         { 0x0700, "program" },
  110         { 0x0800, "floating-point unavailable" },
  111         { 0x0900, "decrementer" },
  112         { 0x0c00, "system call" },
  113         { 0x0d00, "trace" },
  114         { 0x0e00, "floating-point assist" },
  115         { 0x0f00, "performance monitoring" },
  116         { 0x0f20, "altivec unavailable" },
  117         { 0x1000, "instruction tlb miss" },
  118         { 0x1100, "data load tlb miss" },
  119         { 0x1200, "data store tlb miss" },
  120         { 0x1300, "instruction breakpoint" },
  121         { 0x1400, "system management" },
  122         { 0x1600, "altivec assist" },
  123         { 0x1700, "thermal management" },
  124         { 0x2000, "run mode/trace" },
  125         { 0x3000, NULL }
  126 };
  127 
  128 static const char *
  129 trapname(u_int vector)
  130 {
  131         struct  powerpc_exception *pe;
  132 
  133         for (pe = powerpc_exceptions; pe->vector != 0x3000; pe++) {
  134                 if (pe->vector == vector)
  135                         return (pe->name);
  136         }
  137 
  138         return ("unknown");
  139 }
  140 
  141 void
  142 trap(struct trapframe *frame)
  143 {
  144         struct thread   *td;
  145         struct proc     *p;
  146         int             sig, type, user;
  147         u_int           ucode;
  148         ksiginfo_t      ksi;
  149 
  150         PCPU_INC(cnt.v_trap);
  151 
  152         td = PCPU_GET(curthread);
  153         p = td->td_proc;
  154 
  155         type = ucode = frame->exc;
  156         sig = 0;
  157         user = frame->srr1 & PSL_PR;
  158 
  159         CTR3(KTR_TRAP, "trap: %s type=%s (%s)", p->p_comm,
  160             trapname(type), user ? "user" : "kernel");
  161 
  162         if (user) {
  163                 td->td_pticks = 0;
  164                 td->td_frame = frame;
  165                 if (td->td_ucred != p->p_ucred)
  166                         cred_update_thread(td);
  167 
  168                 /* User Mode Traps */
  169                 switch (type) {
  170                 case EXC_RUNMODETRC:
  171                 case EXC_TRC:
  172                         frame->srr1 &= ~PSL_SE;
  173                         sig = SIGTRAP;
  174                         break;
  175 
  176                 case EXC_DSI:
  177                 case EXC_ISI:
  178                         sig = trap_pfault(frame, 1);
  179                         break;
  180 
  181                 case EXC_SC:
  182                         syscall(frame);
  183                         break;
  184 
  185                 case EXC_FPU:
  186                         KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU,
  187                             ("FPU already enabled for thread"));
  188                         enable_fpu(td);
  189                         break;
  190 
  191 #ifdef  ALTIVEC
  192                 case EXC_VEC:
  193                         if ((vecthread = PCPU_GET(vecthread)) != NULL) {
  194                                 KASSERT(vecthread != td,
  195                                     ("altivec already enabled"));
  196                                 save_vec(vecthread);
  197                         }
  198                         PCPU_SET(vecthread, td);
  199                         td->td_pcb->pcb_veccpu = PCPU_GET(cpuid);
  200                         enable_vec(td);
  201                         frame->srr1 |= PSL_VEC;
  202                         break;
  203 #else
  204                 case EXC_VEC:
  205                 case EXC_VECAST:
  206                         sig = SIGILL;
  207                         break;
  208 #endif /* ALTIVEC */
  209 
  210                 case EXC_ALI:
  211                         if (fix_unaligned(td, frame) != 0)
  212                                 sig = SIGBUS;
  213                         else
  214                                 frame->srr0 += 4;
  215                         break;
  216 
  217                 case EXC_PGM:
  218                         /* XXX temporarily */
  219                         /* XXX: Magic Number? */
  220                         if (frame->srr1 & 0x0002000)
  221                                 sig = SIGTRAP;
  222                         else
  223                                 sig = SIGILL;
  224                         break;
  225 
  226                 default:
  227                         trap_fatal(frame);
  228                 }
  229         } else {
  230                 /* Kernel Mode Traps */
  231 
  232                 KASSERT(cold || td->td_ucred != NULL,
  233                     ("kernel trap doesn't have ucred"));
  234                 switch (type) {
  235                 case EXC_DSI:
  236                         if (trap_pfault(frame, 0) == 0)
  237                                 return;
  238                         break;
  239                 case EXC_MCHK:
  240                         if (handle_onfault(frame))
  241                                 return;
  242                         break;
  243                 default:
  244                         break;
  245                 }
  246                 trap_fatal(frame);
  247         }
  248 
  249 #ifdef  ALTIVEC
  250         if (td != PCPU_GET(vecthread) ||
  251             td->td_pcb->pcb_veccpu != PCPU_GET(cpuid))
  252                 frame->srr1 &= ~PSL_VEC;
  253 #endif /* ALTIVEC */
  254 
  255         if (sig != 0) {
  256                 if (p->p_sysent->sv_transtrap != NULL)
  257                         sig = (p->p_sysent->sv_transtrap)(sig, type);
  258                 ksiginfo_init_trap(&ksi);
  259                 ksi.ksi_signo = sig;
  260                 ksi.ksi_code = (int) ucode; /* XXX, not POSIX */
  261                 /* ksi.ksi_addr = ? */
  262                 ksi.ksi_trapno = type;
  263                 trapsignal(td, &ksi);
  264         }
  265 
  266         userret(td, frame);
  267         mtx_assert(&Giant, MA_NOTOWNED);
  268 }
  269 
  270 static void
  271 trap_fatal(struct trapframe *frame)
  272 {
  273 
  274         printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR));
  275 #ifdef KDB
  276         if ((debugger_on_panic || kdb_active) &&
  277             kdb_trap(frame->exc, 0, frame))
  278                 return;
  279 #endif
  280         panic("%s trap", trapname(frame->exc));
  281 }
  282 
  283 static void
  284 printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
  285 {
  286 
  287         printf("\n");
  288         printf("%s %s trap:\n", isfatal ? "fatal" : "handled",
  289             user ? "user" : "kernel");
  290         printf("\n");
  291         printf("   exception       = 0x%x (%s)\n", vector >> 8,
  292             trapname(vector));
  293         switch (vector) {
  294         case EXC_DSI:
  295                 printf("   virtual address = 0x%x\n", frame->dar);
  296                 break;
  297         case EXC_ISI:
  298                 printf("   virtual address = 0x%x\n", frame->srr0);
  299                 break;
  300         }
  301         printf("   srr0            = 0x%x\n", frame->srr0);
  302         printf("   srr1            = 0x%x\n", frame->srr1);
  303         printf("   curthread       = %p\n", curthread);
  304         if (curthread != NULL)
  305                 printf("          pid = %d, comm = %s\n",
  306                     curthread->td_proc->p_pid, curthread->td_proc->p_comm);
  307         printf("\n");
  308 }
  309 
  310 /*
  311  * Handles a fatal fault when we have onfault state to recover.  Returns
  312  * non-zero if there was onfault recovery state available.
  313  */
  314 static int
  315 handle_onfault(struct trapframe *frame)
  316 {
  317         struct          thread *td;
  318         faultbuf        *fb;
  319 
  320         td = curthread;
  321         fb = td->td_pcb->pcb_onfault;
  322         if (fb != NULL) {
  323                 frame->srr0 = (*fb)[0];
  324                 frame->fixreg[1] = (*fb)[1];
  325                 frame->fixreg[2] = (*fb)[2];
  326                 frame->fixreg[3] = 1;
  327                 frame->cr = (*fb)[3];
  328                 bcopy(&(*fb)[4], &frame->fixreg[13],
  329                     19 * sizeof(register_t));
  330                 return (1);
  331         }
  332         return (0);
  333 }
  334 
  335 void
  336 syscall(struct trapframe *frame)
  337 {
  338         caddr_t         params;
  339         struct          sysent *callp;
  340         struct          thread *td;
  341         struct          proc *p;
  342         int             error, n;
  343         size_t          narg;
  344         register_t      args[10];
  345         u_int           code;
  346 
  347         td = PCPU_GET(curthread);
  348         p = td->td_proc;
  349 
  350         PCPU_INC(cnt.v_syscall);
  351 
  352 #ifdef KSE
  353         if (p->p_flag & P_SA)
  354                 thread_user_enter(td);
  355 #endif
  356 
  357         code = frame->fixreg[0];
  358         params = (caddr_t)(frame->fixreg + FIRSTARG);
  359         n = NARGREG;
  360 
  361         if (p->p_sysent->sv_prepsyscall) {
  362                 /*
  363                  * The prep code is MP aware.
  364                  */
  365                 (*p->p_sysent->sv_prepsyscall)(frame, args, &code, &params);
  366         } else if (code == SYS_syscall) {
  367                 /*
  368                  * code is first argument,
  369                  * followed by actual args.
  370                  */
  371                 code = *(u_int *) params;
  372                 params += sizeof(register_t);
  373                 n -= 1;
  374         } else if (code == SYS___syscall) {
  375                 /*
  376                  * Like syscall, but code is a quad,
  377                  * so as to maintain quad alignment
  378                  * for the rest of the args.
  379                  */
  380                 params += sizeof(register_t);
  381                 code = *(u_int *) params;
  382                 params += sizeof(register_t);
  383                 n -= 2;
  384         }
  385 
  386         if (p->p_sysent->sv_mask)
  387                 code &= p->p_sysent->sv_mask;
  388 
  389         if (code >= p->p_sysent->sv_size)
  390                 callp = &p->p_sysent->sv_table[0];
  391         else
  392                 callp = &p->p_sysent->sv_table[code];
  393 
  394         narg = callp->sy_narg;
  395 
  396         if (narg > n) {
  397                 bcopy(params, args, n * sizeof(register_t));
  398                 error = copyin(MOREARGS(frame->fixreg[1]), args + n,
  399                                (narg - n) * sizeof(register_t));
  400                 params = (caddr_t)args;
  401         } else
  402                 error = 0;
  403 
  404         CTR5(KTR_SYSC, "syscall: p=%s %s(%x %x %x)", p->p_comm,
  405              syscallnames[code],
  406              frame->fixreg[FIRSTARG],
  407              frame->fixreg[FIRSTARG+1],
  408              frame->fixreg[FIRSTARG+2]);
  409 
  410 #ifdef  KTRACE
  411         if (KTRPOINT(td, KTR_SYSCALL))
  412                 ktrsyscall(code, narg, (register_t *)params);
  413 #endif
  414 
  415         td->td_syscalls++;
  416 
  417         if (error == 0) {
  418                 td->td_retval[0] = 0;
  419                 td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
  420 
  421                 STOPEVENT(p, S_SCE, narg);
  422 
  423                 PTRACESTOP_SC(p, td, S_PT_SCE);
  424 
  425                 AUDIT_SYSCALL_ENTER(code, td);
  426                 error = (*callp->sy_call)(td, params);
  427                 AUDIT_SYSCALL_EXIT(error, td);
  428 
  429                 CTR3(KTR_SYSC, "syscall: p=%s %s ret=%x", p->p_comm,
  430                      syscallnames[code], td->td_retval[0]);
  431         }
  432         switch (error) {
  433         case 0:
  434                 if (frame->fixreg[0] == SYS___syscall &&
  435                     code != SYS_freebsd6_lseek && code != SYS_lseek) {
  436                         /*
  437                          * 64-bit return, 32-bit syscall. Fixup byte order
  438                          */
  439                         frame->fixreg[FIRSTARG] = 0;
  440                         frame->fixreg[FIRSTARG + 1] = td->td_retval[0];
  441                 } else {
  442                         frame->fixreg[FIRSTARG] = td->td_retval[0];
  443                         frame->fixreg[FIRSTARG + 1] = td->td_retval[1];
  444                 }
  445                 /* XXX: Magic number */
  446                 frame->cr &= ~0x10000000;
  447                 break;
  448         case ERESTART:
  449                 /*
  450                  * Set user's pc back to redo the system call.
  451                  */
  452                 frame->srr0 -= 4;
  453                 break;
  454         case EJUSTRETURN:
  455                 /* nothing to do */
  456                 break;
  457         default:
  458                 if (p->p_sysent->sv_errsize) {
  459                         if (error >= p->p_sysent->sv_errsize)
  460                                 error = -1;     /* XXX */
  461                         else
  462                                 error = p->p_sysent->sv_errtbl[error];
  463                 }
  464                 frame->fixreg[FIRSTARG] = error;
  465                 /* XXX: Magic number: Carry Flag Equivalent? */
  466                 frame->cr |= 0x10000000;
  467                 break;
  468         }
  469 
  470         /*
  471          * Check for misbehavior.
  472          */
  473         WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
  474             (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
  475         KASSERT(td->td_critnest == 0,
  476             ("System call %s returning in a critical section",
  477             (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
  478         KASSERT(td->td_locks == 0,
  479             ("System call %s returning with %d locks held",
  480             (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
  481             td->td_locks));
  482 
  483 #ifdef  KTRACE
  484         if (KTRPOINT(td, KTR_SYSRET))
  485                 ktrsysret(code, error, td->td_retval[0]);
  486 #endif
  487 
  488         /*
  489          * Does the comment in the i386 code about errno apply here?
  490          */
  491         STOPEVENT(p, S_SCX, code);
  492  
  493         PTRACESTOP_SC(p, td, S_PT_SCX);
  494 }
  495 
  496 static int
  497 trap_pfault(struct trapframe *frame, int user)
  498 {
  499         vm_offset_t     eva, va;
  500         struct          thread *td;
  501         struct          proc *p;
  502         vm_map_t        map;
  503         vm_prot_t       ftype;
  504         int             rv;
  505         u_int           user_sr;
  506 
  507         td = curthread;
  508         p = td->td_proc;
  509         if (frame->exc == EXC_ISI) {
  510                 eva = frame->srr0;
  511                 ftype = VM_PROT_READ | VM_PROT_EXECUTE;
  512         } else {
  513                 eva = frame->dar;
  514                 if (frame->dsisr & DSISR_STORE)
  515                         ftype = VM_PROT_WRITE;
  516                 else
  517                         ftype = VM_PROT_READ;
  518         }
  519 
  520         if (user) {
  521                 map = &p->p_vmspace->vm_map;
  522         } else {
  523                 if ((eva >> ADDR_SR_SHFT) == USER_SR) {
  524                         if (p->p_vmspace == NULL)
  525                                 return (SIGSEGV);
  526 
  527                         __asm ("mfsr %0, %1"
  528                             : "=r"(user_sr)
  529                             : "K"(USER_SR));
  530                         eva &= ADDR_PIDX | ADDR_POFF;
  531                         eva |= user_sr << ADDR_SR_SHFT;
  532                         map = &p->p_vmspace->vm_map;
  533                 } else {
  534                         map = kernel_map;
  535                 }
  536         }
  537         va = trunc_page(eva);
  538 
  539         if (map != kernel_map) {
  540                 /*
  541                  * Keep swapout from messing with us during this
  542                  *      critical time.
  543                  */
  544                 PROC_LOCK(p);
  545                 ++p->p_lock;
  546                 PROC_UNLOCK(p);
  547 
  548                 /* Fault in the user page: */
  549                 rv = vm_fault(map, va, ftype,
  550                       (ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY
  551                                               : VM_FAULT_NORMAL);
  552 
  553                 PROC_LOCK(p);
  554                 --p->p_lock;
  555                 PROC_UNLOCK(p);
  556         } else {
  557                 /*
  558                  * Don't have to worry about process locking or stacks in the
  559                  * kernel.
  560                  */
  561                 rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
  562         }
  563 
  564         if (rv == KERN_SUCCESS)
  565                 return (0);
  566 
  567         if (!user && handle_onfault(frame))
  568                 return (0);
  569 
  570         return (SIGSEGV);
  571 }
  572 
  573 static __inline void
  574 setusr(u_int content)
  575 {
  576         __asm __volatile ("isync; mtsr %0,%1; isync"
  577                       :: "n"(USER_SR), "r"(content));
  578 }
  579 
  580 int
  581 badaddr(void *addr, size_t size)
  582 {
  583         return (badaddr_read(addr, size, NULL));
  584 }
  585 
  586 int
  587 badaddr_read(void *addr, size_t size, int *rptr)
  588 {
  589         struct thread   *td;
  590         faultbuf        env;
  591         int             x;
  592 
  593         /* Get rid of any stale machine checks that have been waiting.  */
  594         __asm __volatile ("sync; isync");
  595 
  596         td = PCPU_GET(curthread);
  597 
  598         if (setfault(env)) {
  599                 td->td_pcb->pcb_onfault = 0;
  600                 __asm __volatile ("sync");
  601                 return 1;
  602         }
  603 
  604         __asm __volatile ("sync");
  605 
  606         switch (size) {
  607         case 1:
  608                 x = *(volatile int8_t *)addr;
  609                 break;
  610         case 2:
  611                 x = *(volatile int16_t *)addr;
  612                 break;
  613         case 4:
  614                 x = *(volatile int32_t *)addr;
  615                 break;
  616         default:
  617                 panic("badaddr: invalid size (%d)", size);
  618         }
  619 
  620         /* Make sure we took the machine check, if we caused one. */
  621         __asm __volatile ("sync; isync");
  622 
  623         td->td_pcb->pcb_onfault = 0;
  624         __asm __volatile ("sync");      /* To be sure. */
  625 
  626         /* Use the value to avoid reorder. */
  627         if (rptr)
  628                 *rptr = x;
  629 
  630         return (0);
  631 }
  632 
  633 /*
  634  * For now, this only deals with the particular unaligned access case
  635  * that gcc tends to generate.  Eventually it should handle all of the
  636  * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
  637  */
  638 
  639 static int
  640 fix_unaligned(struct thread *td, struct trapframe *frame)
  641 {
  642         struct thread   *fputhread;
  643         int             indicator, reg;
  644         double          *fpr;
  645 
  646         indicator = EXC_ALI_OPCODE_INDICATOR(frame->dsisr);
  647 
  648         switch (indicator) {
  649         case EXC_ALI_LFD:
  650         case EXC_ALI_STFD:
  651                 reg = EXC_ALI_RST(frame->dsisr);
  652                 fpr = &td->td_pcb->pcb_fpu.fpr[reg];
  653                 fputhread = PCPU_GET(fputhread);
  654 
  655                 /* Juggle the FPU to ensure that we've initialized
  656                  * the FPRs, and that their current state is in
  657                  * the PCB.
  658                  */
  659                 if (fputhread != td) {
  660                         if (fputhread)
  661                                 save_fpu(fputhread);
  662                         enable_fpu(td);
  663                 }
  664                 save_fpu(td);
  665 
  666                 if (indicator == EXC_ALI_LFD) {
  667                         if (copyin((void *)frame->dar, fpr,
  668                             sizeof(double)) != 0)
  669                                 return -1;
  670                         enable_fpu(td);
  671                 } else {
  672                         if (copyout(fpr, (void *)frame->dar,
  673                             sizeof(double)) != 0)
  674                                 return -1;
  675                 }
  676                 return 0;
  677                 break;
  678         }
  679 
  680         return -1;
  681 }
Cache object: 378d498228dd3e77040109c751cddd59
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FreeBSD/Linux Kernel Cross Reference sys/powerpc/powerpc/trap.c

FreeBSD/Linux Kernel Cross Reference
sys/powerpc/powerpc/trap.c
