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Fixed task switch to V86 mode.

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This commit is contained in:
SarahW 2017-07-24 19:36:46 +01:00
commit 9946bf2b73
1 changed files with 57 additions and 56 deletions
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127
src/x86seg.c
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@ -2558,79 +2558,80 @@ void taskswitch286(uint16_t seg, uint16_t *segdat, int is32)
// if (output) pclog("Limit %04X Base %08X\n",ldt.limit,ldt.base);
if (eflags&VM_FLAG)
if (eflags & VM_FLAG)
{
pclog("Task switch V86!\n");
x86gpf(NULL,0);
return;
}
if (!(new_cs&~3))
{
pclog("TS loading null CS\n");
x86ts(NULL,0);
return;
}
addr=new_cs&~7;
if (new_cs&4)
{
if (addr>=ldt.limit)
{
pclog("Bigger than LDT limit %04X %04X %04X TS\n",new_cs,ldt.limit,addr);
x86ts(NULL,new_cs&~3);
return;
}
addr+=ldt.base;
loadcs(new_cs);
set_use32(0);
}
else
{
if (addr>=gdt.limit)
if (!(new_cs&~3))
{
pclog("Bigger than GDT limit %04X %04X TS\n",new_cs,gdt.limit);
pclog("TS loading null CS\n");
x86ts(NULL,0);
return;
}
addr=new_cs&~7;
if (new_cs&4)
{
if (addr>=ldt.limit)
{
pclog("Bigger than LDT limit %04X %04X %04X TS\n",new_cs,ldt.limit,addr);
x86ts(NULL,new_cs&~3);
return;
}
addr+=ldt.base;
}
else
{
if (addr>=gdt.limit)
{
pclog("Bigger than GDT limit %04X %04X TS\n",new_cs,gdt.limit);
x86ts(NULL,new_cs&~3);
return;
}
addr+=gdt.base;
}
segdat2[0]=readmemw(0,addr);
segdat2[1]=readmemw(0,addr+2);
segdat2[2]=readmemw(0,addr+4);
segdat2[3]=readmemw(0,addr+6);
if (!(segdat2[2]&0x8000))
{
pclog("TS loading CS not present\n");
x86np("TS loading CS not present\n", new_cs & 0xfffc);
return;
}
switch (segdat2[2]&0x1F00)
{
case 0x1800: case 0x1900: case 0x1A00: case 0x1B00: /*Non-conforming*/
if ((new_cs&3) != DPL2)
{
pclog("TS load CS non-conforming RPL != DPL");
x86ts(NULL,new_cs&~3);
return;
}
break;
case 0x1C00: case 0x1D00: case 0x1E00: case 0x1F00: /*Conforming*/
if ((new_cs&3) < DPL2)
{
pclog("TS load CS non-conforming RPL < DPL");
x86ts(NULL,new_cs&~3);
return;
}
break;
default:
pclog("TS load CS not code segment\n");
x86ts(NULL,new_cs&~3);
return;
}
addr+=gdt.base;
}
segdat2[0]=readmemw(0,addr);
segdat2[1]=readmemw(0,addr+2);
segdat2[2]=readmemw(0,addr+4);
segdat2[3]=readmemw(0,addr+6);
if (!(segdat2[2]&0x8000))
{
pclog("TS loading CS not present\n");
x86np("TS loading CS not present\n", new_cs & 0xfffc);
return;
}
switch (segdat2[2]&0x1F00)
{
case 0x1800: case 0x1900: case 0x1A00: case 0x1B00: /*Non-conforming*/
if ((new_cs&3) != DPL2)
{
pclog("TS load CS non-conforming RPL != DPL");
x86ts(NULL,new_cs&~3);
return;
}
break;
case 0x1C00: case 0x1D00: case 0x1E00: case 0x1F00: /*Conforming*/
if ((new_cs&3) < DPL2)
{
pclog("TS load CS non-conforming RPL < DPL");
x86ts(NULL,new_cs&~3);
return;
}
break;
default:
pclog("TS load CS not code segment\n");
x86ts(NULL,new_cs&~3);
return;
}
// if (output) pclog("new_cs %04X\n",new_cs);
CS=new_cs;
do_seg_load(&_cs, segdat2);
if (CPL==3 && oldcpl!=3) flushmmucache_cr3();
set_use32(segdat2[3] & 0x40);
CS=new_cs;
do_seg_load(&_cs, segdat2);
if (CPL==3 && oldcpl!=3) flushmmucache_cr3();
set_use32(segdat2[3] & 0x40);
}
EAX=new_eax;
ECX=new_ecx;