e4ce6aadac
we might as well handle the per process cycle counter in the portable part instead of duplicating the code in every arch and have inconsistent implementations. we now have a portable kenter() and kexit() function, that is ment to be used in trap/syscall from user, which updates the counters. some kernels missed initializing Mach.cyclefreq.
798 lines
18 KiB
C
798 lines
18 KiB
C
#include "u.h"
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#include "tos.h"
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#include "../port/lib.h"
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#include "mem.h"
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#include "dat.h"
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#include "fns.h"
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#include "io.h"
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#include "ureg.h"
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#include "../port/error.h"
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#include <trace.h>
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#define INTRLOG(a)
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#define SETUPLOG(a)
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#define SYSCALLLOG(a)
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#define FAULTLOG(a)
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#define FAULTLOGFAST(a)
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#define POSTNOTELOG(a)
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#define TRAPLOG(a)
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int faultpanic = 0;
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enum {
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/* trap_info_t flags */
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SPL0 = 0,
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SPL3 = 3,
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EvDisable = 4,
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};
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void noted(Ureg*, ulong);
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extern void irqinit(void);
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extern int irqhandled(Ureg*, int);
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static void debugbpt(Ureg*, void*);
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static void fault386(Ureg*, void*);
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static void safe_fault386(Ureg*, void*);
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static void doublefault(Ureg*, void*);
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static void unexpected(Ureg*, void*);
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static void _dumpstack(Ureg*);
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/* we started out doing the 'giant bulk init' for all traps.
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* we're going to do them one-by-one since error analysis is
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* so much easier that way.
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*/
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void
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trapinit(void)
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{
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trap_info_t t[2];
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ulong vaddr;
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int v, flag;
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HYPERVISOR_set_callbacks(
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KESEL, (ulong)hypervisor_callback,
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KESEL, (ulong)failsafe_callback);
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/* XXX rework as single hypercall once debugged */
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t[1].address = 0;
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vaddr = (ulong)vectortable;
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for(v = 0; v < 256; v++){
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switch(v){
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case VectorBPT:
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case VectorSYSCALL:
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flag = SPL3 | EvDisable;
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break;
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default:
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flag = SPL0 | EvDisable;
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break;
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}
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t[0] = (trap_info_t){ v, flag, KESEL, vaddr };
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if(HYPERVISOR_set_trap_table(t) < 0)
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panic("trapinit: FAIL: try to set: 0x%x, 0x%x, 0x%x, 0x%ulx\n",
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t[0].vector, t[0].flags, t[0].cs, t[0].address);
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vaddr += 6;
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}
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irqinit();
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/*
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* Special traps.
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* Syscall() is called directly without going through trap().
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*/
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trapenable(VectorBPT, debugbpt, 0, "debugpt");
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trapenable(VectorPF, fault386, 0, "fault386");
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trapenable(Vector2F, doublefault, 0, "doublefault");
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trapenable(Vector15, unexpected, 0, "unexpected");
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}
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static char* excname[32] = {
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"divide error",
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"debug exception",
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"nonmaskable interrupt",
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"breakpoint",
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"overflow",
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"bounds check",
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"invalid opcode",
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"coprocessor not available",
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"double fault",
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"coprocessor segment overrun",
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"invalid TSS",
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"segment not present",
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"stack exception",
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"general protection violation",
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"page fault",
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"15 (reserved)",
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"coprocessor error",
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"alignment check",
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"machine check",
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"19 (reserved)",
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"20 (reserved)",
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"21 (reserved)",
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"22 (reserved)",
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"23 (reserved)",
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"24 (reserved)",
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"25 (reserved)",
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"26 (reserved)",
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"27 (reserved)",
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"28 (reserved)",
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"29 (reserved)",
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"30 (reserved)",
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"31 (reserved)",
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};
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static int
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usertrap(int vno)
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{
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char buf[ERRMAX];
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if(vno < nelem(excname)){
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spllo();
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sprint(buf, "sys: trap: %s", excname[vno]);
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postnote(up, 1, buf, NDebug);
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return 1;
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}
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return 0;
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}
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/*
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* All traps come here. It is slower to have all traps call trap()
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* rather than directly vectoring the handler. However, this avoids a
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* lot of code duplication and possible bugs. The only exception is
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* VectorSYSCALL.
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* Trap is called with interrupts disabled via interrupt-gates.
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*/
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void
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trap(Ureg* ureg)
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{
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int vno, user;
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user = kenter(ureg);
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vno = ureg->trap;
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if(!irqhandled(ureg, vno) && (!user || !usertrap(vno))){
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if(!user){
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/* early fault before trapinit() */
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if(vno == VectorPF)
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fault386(ureg, 0);
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}
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dumpregs(ureg);
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if(!user){
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ureg->sp = (ulong)&ureg->sp;
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_dumpstack(ureg);
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}
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if(vno < nelem(excname))
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panic("%s", excname[vno]);
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panic("unknown trap/intr: %d", vno);
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}
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splhi();
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if(user){
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if(up->procctl || up->nnote)
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notify(ureg);
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kexit(ureg);
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}
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if (ureg->trap == 0xe) {
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/*
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* on page fault, we need to restore the old spl
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* Xen won't do it for us.
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* XXX verify this.
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*/
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if (ureg->flags & 0x200)
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spllo();
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}
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}
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void
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dumpregs2(Ureg* ureg)
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{
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if(up)
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print("cpu%d: registers for %s %lud\n",
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m->machno, up->text, up->pid);
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else
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print("cpu%d: registers for kernel\n", m->machno);
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print("FLAGS=%luX TRAP=%luX ECODE=%luX PC=%luX",
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ureg->flags, ureg->trap, ureg->ecode, ureg->pc);
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print(" SS=%4.4luX USP=%luX\n", ureg->ss & 0xFFFF, ureg->usp);
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print(" AX %8.8luX BX %8.8luX CX %8.8luX DX %8.8luX\n",
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ureg->ax, ureg->bx, ureg->cx, ureg->dx);
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print(" SI %8.8luX DI %8.8luX BP %8.8luX\n",
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ureg->si, ureg->di, ureg->bp);
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print(" CS %4.4luX DS %4.4luX ES %4.4luX FS %4.4luX GS %4.4luX\n",
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ureg->cs & 0xFFFF, ureg->ds & 0xFFFF, ureg->es & 0xFFFF,
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ureg->fs & 0xFFFF, ureg->gs & 0xFFFF);
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}
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void
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dumpregs(Ureg* ureg)
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{
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extern ulong etext;
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dumpregs2(ureg);
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/*
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* Processor control registers.
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* If machine check exception, time stamp counter, page size extensions
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* or enhanced virtual 8086 mode extensions are supported, there is a
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* CR4. If there is a CR4 and machine check extensions, read the machine
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* check address and machine check type registers if RDMSR supported.
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*/
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print("SKIPPING get of crx and other such stuff.\n");/* */
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#ifdef NOT
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print(" CR0 %8.8lux CR2 %8.8lux CR3 %8.8lux",
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getcr0(), getcr2(), getcr3());
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if(m->cpuiddx & 0x9A){
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print(" CR4 %8.8lux", getcr4());
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if((m->cpuiddx & 0xA0) == 0xA0){
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rdmsr(0x00, &mca);
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rdmsr(0x01, &mct);
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print("\n MCA %8.8llux MCT %8.8llux", mca, mct);
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}
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}
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#endif
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print("\n ur %lux up %lux\n", (ulong)ureg, (ulong)up);
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}
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/*
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* Fill in enough of Ureg to get a stack trace, and call a function.
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* Used by debugging interface rdb.
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*/
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void
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callwithureg(void (*fn)(Ureg*))
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{
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Ureg ureg;
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ureg.pc = getcallerpc(&fn);
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ureg.sp = (ulong)&fn;
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fn(&ureg);
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}
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static void
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_dumpstack(Ureg *ureg)
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{
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ulong l, v, i, estack;
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extern ulong etext;
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int x;
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if(getconf("*nodumpstack")){
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iprint("dumpstack disabled\n");
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return;
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}
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iprint("dumpstack\n");
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x = 0;
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x += print("ktrace /kernel/path %.8lux %.8lux <<EOF\n", ureg->pc, ureg->sp);
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i = 0;
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if(up
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&& (ulong)&l >= (ulong)up->kstack
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&& (ulong)&l <= (ulong)up->kstack+KSTACK)
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estack = (ulong)up->kstack+KSTACK;
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else if((ulong)&l >= (ulong)m->stack
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&& (ulong)&l <= (ulong)m+BY2PG)
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estack = (ulong)m+MACHSIZE;
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else
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return;
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x += print("estackx %.8lux\n", estack);
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for(l=(ulong)&l; l<estack; l+=4){
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v = *(ulong*)l;
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if((KTZERO < v && v < (ulong)&etext) || estack-l<32){
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/*
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* we could Pick off general CALL (((uchar*)v)[-5] == 0xE8)
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* and CALL indirect through AX (((uchar*)v)[-2] == 0xFF && ((uchar*)v)[-2] == 0xD0),
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* but this is too clever and misses faulting address.
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*/
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x += print("%.8lux=%.8lux ", l, v);
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i++;
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}
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if(i == 4){
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i = 0;
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x += print("\n");
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}
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}
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if(i)
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print("\n");
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print("EOF\n");
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}
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void
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dumpstack(void)
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{
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callwithureg(_dumpstack);
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}
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static void
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debugbpt(Ureg* ureg, void*)
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{
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char buf[ERRMAX];
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print("debugbpt\n");
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if(up == 0)
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panic("kernel bpt");
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/* restore pc to instruction that caused the trap */
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ureg->pc--;
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sprint(buf, "sys: breakpoint");
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postnote(up, 1, buf, NDebug);
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print("debugbpt for proc %lud\n", up->pid);
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}
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static void
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doublefault(Ureg*, void*)
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{
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panic("double fault");
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}
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static void
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unexpected(Ureg* ureg, void*)
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{
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print("unexpected trap %lud; ignoring\n", ureg->trap);
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}
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static void
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fault386(Ureg* ureg, void*)
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{
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ulong addr;
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int read, user, n, insyscall;
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char buf[ERRMAX];
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addr = HYPERVISOR_shared_info->vcpu_info[m->machno].arch.cr2;
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if (faultpanic) {
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dprint("cr2 is 0x%lx\n", addr);
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//dumpregs(ureg);
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dumpstack();
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panic("fault386");
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exit(1);
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}
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user = (ureg->cs & 0xFFFF) == UESEL;
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if(!user && mmukmapsync(addr))
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return;
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read = !(ureg->ecode & 2);
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if(up == nil)
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panic("fault but up is zero; pc 0x%8.8lux addr 0x%8.8lux\n", ureg->pc, addr);
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insyscall = up->insyscall;
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up->insyscall = 1;
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n = fault(addr, ureg->pc, read);
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if(n < 0){
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if(!user){
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dumpregs(ureg);
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panic("fault: 0x%lux\n", addr);
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}
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sprint(buf, "sys: trap: fault %s addr=0x%lux",
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read? "read" : "write", addr);
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dprint("Posting %s to %lud\n", buf, up->pid);
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postnote(up, 1, buf, NDebug);
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}
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up->insyscall = insyscall;
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FAULTLOG(dprint("fault386: all done\n");)
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}
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/*
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* system calls
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*/
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#include "../port/systab.h"
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/*
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* Syscall is called directly from assembler without going through trap().
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*/
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void
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syscall(Ureg* ureg)
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{
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char *e;
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ulong sp;
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long ret;
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int i, s;
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ulong scallnr;
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SYSCALLLOG(dprint("%d: syscall ...#%ld(%s)\n",
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up->pid, ureg->ax, sysctab[ureg->ax]);)
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if(!kenter(ureg))
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panic("syscall: cs 0x%4.4luX\n", ureg->cs);
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m->syscall++;
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up->insyscall = 1;
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up->pc = ureg->pc;
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if(up->procctl == Proc_tracesyscall){
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up->procctl = Proc_stopme;
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procctl();
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}
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scallnr = ureg->ax;
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up->scallnr = scallnr;
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if(scallnr == RFORK && up->fpstate == FPactive){
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fpsave(up->fpsave);
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up->fpstate = FPinactive;
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}
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spllo();
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sp = ureg->usp;
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up->nerrlab = 0;
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ret = -1;
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if(!waserror()){
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if(scallnr >= nsyscall || systab[scallnr] == 0){
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pprint("bad sys call number %lud pc %lux\n",
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scallnr, ureg->pc);
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postnote(up, 1, "sys: bad sys call", NDebug);
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error(Ebadarg);
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}
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if(sp<(USTKTOP-BY2PG) || sp>(USTKTOP-sizeof(Sargs)-BY2WD))
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validaddr(sp, sizeof(Sargs)+BY2WD, 0);
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up->s = *((Sargs*)(sp+BY2WD));
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up->psstate = sysctab[scallnr];
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ret = systab[scallnr]((va_list)up->s.args);
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poperror();
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}else{
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/* failure: save the error buffer for errstr */
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e = up->syserrstr;
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up->syserrstr = up->errstr;
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up->errstr = e;
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if(0 && up->pid == 1)
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print("syscall %lud error %s\n", scallnr, up->syserrstr);
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}
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if(up->nerrlab){
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print("bad errstack [%lud]: %d extra\n", scallnr, up->nerrlab);
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for(i = 0; i < NERR; i++)
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print("sp=%lux pc=%lux\n",
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up->errlab[i].sp, up->errlab[i].pc);
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panic("error stack");
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}
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SYSCALLLOG(dprint("%d: Syscall %d returns %d, ureg %p\n", up->pid, scallnr, ret, ureg);)
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/*
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* Put return value in frame. On the x86 the syscall is
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* just another trap and the return value from syscall is
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* ignored. On other machines the return value is put into
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* the results register by caller of syscall.
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*/
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ureg->ax = ret;
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if(up->procctl == Proc_tracesyscall){
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s = splhi();
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up->procctl = Proc_stopme;
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procctl();
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splx(s);
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}
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up->insyscall = 0;
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up->psstate = 0;
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INTRLOG(dprint("cleared insyscall\n");)
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if(scallnr == NOTED)
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noted(ureg, *(ulong*)(sp+BY2WD));
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if(scallnr!=RFORK && (up->procctl || up->nnote)){
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splhi();
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notify(ureg);
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}
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/* if we delayed sched because we held a lock, sched now */
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if(up->delaysched)
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sched();
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INTRLOG(dprint("before kexit\n");)
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kexit(ureg);
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}
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/*
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* Call user, if necessary, with note.
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* Pass user the Ureg struct and the note on his stack.
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*/
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int
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notify(Ureg* ureg)
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{
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int l;
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ulong s, sp;
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Note *n;
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if(up->procctl)
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procctl();
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if(up->nnote == 0)
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return 0;
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if(up->fpstate == FPactive){
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fpsave(up->fpsave);
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up->fpstate = FPinactive;
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}
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up->fpstate |= FPillegal;
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s = spllo();
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qlock(&up->debug);
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up->notepending = 0;
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n = &up->note[0];
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if(strncmp(n->msg, "sys:", 4) == 0){
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l = strlen(n->msg);
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if(l > ERRMAX-15) /* " pc=0x12345678\0" */
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l = ERRMAX-15;
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sprint(n->msg+l, " pc=0x%.8lux", ureg->pc);
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}
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if(n->flag!=NUser && (up->notified || up->notify==0)){
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if(n->flag == NDebug)
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pprint("suicide: %s\n", n->msg);
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qunlock(&up->debug);
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pexit(n->msg, n->flag!=NDebug);
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}
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if(up->notified){
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qunlock(&up->debug);
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splhi();
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return 0;
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}
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if(!up->notify){
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qunlock(&up->debug);
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pexit(n->msg, n->flag!=NDebug);
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}
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sp = ureg->usp;
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sp -= sizeof(Ureg);
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if(!okaddr((ulong)up->notify, 1, 0)
|
|
|| !okaddr(sp-ERRMAX-4*BY2WD, sizeof(Ureg)+ERRMAX+4*BY2WD, 1)){
|
|
pprint("suicide: bad address in notify\n");
|
|
qunlock(&up->debug);
|
|
pexit("Suicide", 0);
|
|
}
|
|
|
|
up->ureg = (void*)sp;
|
|
memmove((Ureg*)sp, ureg, sizeof(Ureg));
|
|
*(Ureg**)(sp-BY2WD) = up->ureg; /* word under Ureg is old up->ureg */
|
|
up->ureg = (void*)sp;
|
|
sp -= BY2WD+ERRMAX;
|
|
memmove((char*)sp, up->note[0].msg, ERRMAX);
|
|
sp -= 3*BY2WD;
|
|
*(ulong*)(sp+2*BY2WD) = sp+3*BY2WD; /* arg 2 is string */
|
|
*(ulong*)(sp+1*BY2WD) = (ulong)up->ureg; /* arg 1 is ureg* */
|
|
*(ulong*)(sp+0*BY2WD) = 0; /* arg 0 is pc */
|
|
ureg->usp = sp;
|
|
ureg->pc = (ulong)up->notify;
|
|
up->notified = 1;
|
|
up->nnote--;
|
|
memmove(&up->lastnote, &up->note[0], sizeof(Note));
|
|
memmove(&up->note[0], &up->note[1], up->nnote*sizeof(Note));
|
|
|
|
qunlock(&up->debug);
|
|
splx(s);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Return user to state before notify()
|
|
*/
|
|
void
|
|
noted(Ureg* ureg, ulong arg0)
|
|
{
|
|
Ureg *nureg;
|
|
ulong oureg, sp;
|
|
|
|
qlock(&up->debug);
|
|
if(arg0!=NRSTR && !up->notified) {
|
|
qunlock(&up->debug);
|
|
pprint("call to noted() when not notified\n");
|
|
pexit("Suicide", 0);
|
|
}
|
|
up->notified = 0;
|
|
|
|
nureg = up->ureg; /* pointer to user returned Ureg struct */
|
|
|
|
up->fpstate &= ~FPillegal;
|
|
|
|
/* sanity clause */
|
|
oureg = (ulong)nureg;
|
|
if(!okaddr((ulong)oureg-BY2WD, BY2WD+sizeof(Ureg), 0)){
|
|
pprint("bad ureg in noted or call to noted when not notified\n");
|
|
qunlock(&up->debug);
|
|
pexit("Suicide", 0);
|
|
}
|
|
|
|
/*
|
|
* Check the segment selectors are all valid, otherwise
|
|
* a fault will be taken on attempting to return to the
|
|
* user process.
|
|
* Take care with the comparisons as different processor
|
|
* generations push segment descriptors in different ways.
|
|
*/
|
|
if((nureg->cs & 0xFFFF) != UESEL || (nureg->ss & 0xFFFF) != UDSEL
|
|
|| (nureg->ds & 0xFFFF) != UDSEL || (nureg->es & 0xFFFF) != UDSEL
|
|
|| (nureg->fs & 0xFFFF) != UDSEL || (nureg->gs & 0xFFFF) != UDSEL){
|
|
pprint("bad segment selector in noted\n");
|
|
pprint("cs is %#lux, wanted %#ux\n", nureg->cs, UESEL);
|
|
pprint("ds is %#lux, wanted %#ux\n", nureg->ds, UDSEL);
|
|
pprint("es is %#lux, fs is %#lux, gs %#lux, wanted %#ux\n",
|
|
ureg->es, ureg->fs, ureg->gs, UDSEL);
|
|
pprint("ss is %#lux, wanted %#ux\n", nureg->ss, UDSEL);
|
|
qunlock(&up->debug);
|
|
pexit("Suicide", 0);
|
|
}
|
|
|
|
/* don't let user change system flags */
|
|
nureg->flags = (ureg->flags & ~0xCD5) | (nureg->flags & 0xCD5);
|
|
|
|
memmove(ureg, nureg, sizeof(Ureg));
|
|
|
|
switch(arg0){
|
|
case NCONT:
|
|
case NRSTR:
|
|
if(!okaddr(nureg->pc, 1, 0) || !okaddr(nureg->usp, BY2WD, 0)){
|
|
qunlock(&up->debug);
|
|
pprint("suicide: trap in noted\n");
|
|
pexit("Suicide", 0);
|
|
}
|
|
up->ureg = (Ureg*)(*(ulong*)(oureg-BY2WD));
|
|
qunlock(&up->debug);
|
|
break;
|
|
|
|
case NSAVE:
|
|
if(!okaddr(nureg->pc, BY2WD, 0)
|
|
|| !okaddr(nureg->usp, BY2WD, 0)){
|
|
qunlock(&up->debug);
|
|
pprint("suicide: trap in noted\n");
|
|
pexit("Suicide", 0);
|
|
}
|
|
qunlock(&up->debug);
|
|
sp = oureg-4*BY2WD-ERRMAX;
|
|
splhi();
|
|
ureg->sp = sp;
|
|
((ulong*)sp)[1] = oureg; /* arg 1 0(FP) is ureg* */
|
|
((ulong*)sp)[0] = 0; /* arg 0 is pc */
|
|
break;
|
|
|
|
default:
|
|
pprint("unknown noted arg 0x%lux\n", arg0);
|
|
up->lastnote.flag = NDebug;
|
|
/* fall through */
|
|
|
|
case NDFLT:
|
|
if(up->lastnote.flag == NDebug){
|
|
qunlock(&up->debug);
|
|
pprint("suicide: %s\n", up->lastnote.msg);
|
|
} else
|
|
qunlock(&up->debug);
|
|
pexit(up->lastnote.msg, up->lastnote.flag!=NDebug);
|
|
}
|
|
}
|
|
|
|
uintptr
|
|
execregs(uintptr entry, ulong ssize, ulong nargs)
|
|
{
|
|
ulong *sp;
|
|
Ureg *ureg;
|
|
|
|
up->fpstate = FPinit;
|
|
fpoff();
|
|
|
|
sp = (ulong*)(USTKTOP - ssize);
|
|
*--sp = nargs;
|
|
|
|
ureg = up->dbgreg;
|
|
ureg->usp = (ulong)sp;
|
|
ureg->pc = entry;
|
|
// print("execregs returns 0x%x\n", USTKTOP-sizeof(Tos));
|
|
return USTKTOP-sizeof(Tos); /* address of kernel/user shared data */
|
|
}
|
|
|
|
/*
|
|
* return the userpc the last exception happened at
|
|
*/
|
|
ulong
|
|
userpc(void)
|
|
{
|
|
Ureg *ureg;
|
|
|
|
ureg = (Ureg*)up->dbgreg;
|
|
return ureg->pc;
|
|
}
|
|
|
|
/* This routine must save the values of registers the user is not permitted
|
|
* to write from devproc and then restore the saved values before returning.
|
|
*/
|
|
void
|
|
setregisters(Ureg* ureg, char* pureg, char* uva, int n)
|
|
{
|
|
ulong flags;
|
|
ulong cs;
|
|
ulong ss;
|
|
|
|
flags = ureg->flags;
|
|
cs = ureg->cs;
|
|
ss = ureg->ss;
|
|
memmove(pureg, uva, n);
|
|
ureg->flags = (ureg->flags & 0x00FF) | (flags & 0xFF00);
|
|
ureg->cs = cs;
|
|
ureg->ss = ss;
|
|
}
|
|
|
|
void
|
|
kprocchild(Proc *p, void (*entry)(void))
|
|
{
|
|
/*
|
|
* gotolabel() needs a word on the stack in
|
|
* which to place the return PC used to jump
|
|
* to linkproc().
|
|
*/
|
|
p->sched.pc = (ulong)entry;
|
|
p->sched.sp = (ulong)p->kstack+KSTACK-BY2WD;
|
|
}
|
|
|
|
void
|
|
forkchild(Proc *p, Ureg *ureg)
|
|
{
|
|
Ureg *cureg;
|
|
|
|
/*
|
|
* Add 2*BY2WD to the stack to account for
|
|
* - the return PC
|
|
* - trap's argument (ur)
|
|
*/
|
|
p->sched.sp = (ulong)p->kstack+KSTACK-(sizeof(Ureg)+2*BY2WD);
|
|
p->sched.pc = (ulong)forkret;
|
|
|
|
cureg = (Ureg*)(p->sched.sp+2*BY2WD);
|
|
memmove(cureg, ureg, sizeof(Ureg));
|
|
/* return value of syscall in child */
|
|
cureg->ax = 0;
|
|
}
|
|
|
|
/* Give enough context in the ureg to produce a kernel stack for
|
|
* a sleeping process
|
|
*/
|
|
void
|
|
setkernur(Ureg* ureg, Proc* p)
|
|
{
|
|
ureg->pc = p->sched.pc;
|
|
ureg->sp = p->sched.sp+4;
|
|
}
|
|
|
|
ulong
|
|
dbgpc(Proc *p)
|
|
{
|
|
Ureg *ureg;
|
|
|
|
ureg = p->dbgreg;
|
|
if(ureg == 0)
|
|
return 0;
|
|
|
|
return ureg->pc;
|
|
}
|
|
|
|
/*
|
|
* install_safe_pf_handler / install_normal_pf_handler:
|
|
*
|
|
* These are used within the failsafe_callback handler in entry.S to avoid
|
|
* taking a full page fault when reloading FS and GS. This is because FS and
|
|
* GS could be invalid at pretty much any point while Xenolinux executes (we
|
|
* don't set them to safe values on entry to the kernel). At *any* point Xen
|
|
* may be entered due to a hardware interrupt --- on exit from Xen an invalid
|
|
* FS/GS will cause our failsafe_callback to be executed. This could occur,
|
|
* for example, while the mmu_update_queue is in an inconsistent state. This
|
|
* is disastrous because the normal page-fault handler touches the update
|
|
* queue!
|
|
*
|
|
* Fortunately, within the failsafe handler it is safe to force DS/ES/FS/GS
|
|
* to zero if they cannot be reloaded -- at this point executing a normal
|
|
* page fault would not change this effect. The safe page-fault handler
|
|
* ensures this end result (blow away the selector value) without the dangers
|
|
* of the normal page-fault handler.
|
|
*
|
|
* NB. Perhaps this can all go away after we have implemented writeable
|
|
* page tables. :-)
|
|
*/
|
|
static void
|
|
safe_fault386(Ureg* , void* ) {
|
|
panic("DO SAFE PAGE FAULT!\n");
|
|
|
|
|
|
|
|
}
|
|
|
|
unsigned long install_safe_pf_handler(void)
|
|
{
|
|
dprint("called from failsafe callback\n");
|
|
trapenable(VectorPF, safe_fault386, 0, "safe_fault386");
|
|
return 0;
|
|
}
|
|
|
|
void install_normal_pf_handler(unsigned long)
|
|
{
|
|
trapenable(VectorPF, fault386, 0, "fault386");
|
|
}
|