int get_phy_addr(ull *out_phy_addr, ull pid, ull virt_addr) { int pagemap_fd; char pagemap_path[256]; ull pagesize; ull pagesizemask; ull index; ull offset; ull seek_result; if (pid > 0) { sprintf(pagemap_path, "/proc/%llu/pagemap", pid); } else { // pid == 0 sprintf(pagemap_path, "/proc/self/pagemap"); } pagemap_fd = open(pagemap_path, O_RDONLY); if (pagemap_fd == -1) { fprintf(stderr, "failed to open %s\n", pagemap_path); return -1; } pagesize = (ull)memtester_pagesize(); pagesizemask = ~(pagesize - 1); index = (((virt_addr & pagesizemask) / pagesize) * sizeof(ull)); offset = (virt_addr & (~pagesizemask)); seek_result = (ull)lseek64(pagemap_fd, (off64_t)index, SEEK_SET); if (seek_result != index) { fprintf(stderr, "failed to seek\n"); close(pagemap_fd); return -2; } if (read(pagemap_fd, (void *)out_phy_addr, (size_t)sizeof(ull)) != sizeof(ull)) { fprintf(stderr, "failed to read\n"); close(pagemap_fd); return -3; } close(pagemap_fd); if (IS_PRESENT(*out_phy_addr)) { *out_phy_addr = GET_PFN(*out_phy_addr); *out_phy_addr = *out_phy_addr * pagesize; *out_phy_addr = *out_phy_addr + offset; return 0; } else { fprintf(stderr, "invalide pfn\n"); return -4; } }
void BX_CPU_C::task_switch_load_selector(bx_segment_reg_t *seg, bx_selector_t *selector, Bit16u raw_selector, Bit8u cs_rpl) { bx_descriptor_t descriptor; Bit32u dword1, dword2; // NULL selector is OK, will leave cache invalid if ((raw_selector & 0xfffc) != 0) { bx_bool good = fetch_raw_descriptor2(selector, &dword1, &dword2); if (!good) { BX_ERROR(("task_switch(%s): bad selector fetch !", strseg(seg))); exception(BX_TS_EXCEPTION, raw_selector & 0xfffc, 0); } parse_descriptor(dword1, dword2, &descriptor); /* AR byte must indicate data or readable code segment else #TS(selector) */ if (descriptor.segment==0 || (IS_CODE_SEGMENT(descriptor.type) && IS_CODE_SEGMENT_READABLE(descriptor.type) == 0)) { BX_ERROR(("task_switch(%s): not data or readable code !", strseg(seg))); exception(BX_TS_EXCEPTION, raw_selector & 0xfffc, 0); } /* If data or non-conforming code, then both the RPL and the CPL * must be less than or equal to DPL in AR byte else #GP(selector) */ if (IS_DATA_SEGMENT(descriptor.type) || IS_CODE_SEGMENT_NON_CONFORMING(descriptor.type)) { if ((selector->rpl > descriptor.dpl) || (cs_rpl > descriptor.dpl)) { BX_ERROR(("load_seg_reg(%s): RPL & CPL must be <= DPL", strseg(seg))); exception(BX_TS_EXCEPTION, raw_selector & 0xfffc, 0); } } if (! IS_PRESENT(descriptor)) { BX_ERROR(("task_switch(%s): descriptor not present !", strseg(seg))); exception(BX_NP_EXCEPTION, raw_selector & 0xfffc, 0); } // All checks pass, fill in shadow cache seg->cache = descriptor; } }
static ssize_t show_serial_number(struct device *dev, struct device_attribute *da, char *buf) { struct as5812_54x_psu_data *data = as5812_54x_psu_update_device(dev); if (!data->valid) { return 0; } if (!IS_PRESENT(data->index, data->status)) { return 0; } if (as5812_54x_psu_model_name_get(dev, 1) < 0) { return -ENXIO; } return sprintf(buf, "%s\n", data->serial); }
static ssize_t show_status(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct as5812_54x_psu_data *data = as5812_54x_psu_update_device(dev); u8 status = 0; if (!data->valid) { return sprintf(buf, "0\n"); } if (attr->index == PSU_PRESENT) { status = IS_PRESENT(data->index, data->status); } else { /* PSU_POWER_GOOD */ status = IS_POWER_GOOD(data->index, data->status); } return sprintf(buf, "%d\n", status); }
errorCode getEmptyTypeGrammar(EXIStream* strm, EXIGrammar* src, EXIGrammar** dest) { SmallIndex i; Index p; Index destProdIndx, partNum; *dest = memManagedAllocate(&strm->memList, sizeof(EXIGrammar)); if(*dest == NULL) return MEMORY_ALLOCATION_ERROR; (*dest)->contentIndex = src->contentIndex; (*dest)->count = src->contentIndex; (*dest)->props = src->props; (*dest)->rule = memManagedAllocate(&strm->memList, sizeof(GrammarRule)*((*dest)->count)); if((*dest)->rule == NULL) return MEMORY_ALLOCATION_ERROR; if(WITH_STRICT(strm->header.opts.enumOpt)) { for(i = 0; i < (*dest)->count - 1; i++) { for(partNum = 0; partNum < 3; partNum++) { // Copy all productions in the rules less than contentIndex i.e. (*dest)->count - 1 // except the AT(xsi:type) and AT(xsi:nil) (*dest)->rule[i].part[partNum].prod = memManagedAllocate(&strm->memList, sizeof(Production)*(src->rule[i].part[partNum].count)); if((*dest)->rule[i].part[partNum].prod == NULL) return MEMORY_ALLOCATION_ERROR; destProdIndx = 0; for(p = 0; p < src->rule[i].part[partNum].count; p++) { if(src->rule[i].part[partNum].prod[p].qnameId.uriId == XML_SCHEMA_INSTANCE_ID && (src->rule[i].part[partNum].prod[p].qnameId.lnId == XML_SCHEMA_INSTANCE_NIL_ID || src->rule[i].part[partNum].prod[p].qnameId.lnId == XML_SCHEMA_INSTANCE_TYPE_ID)) { // In case of AT(xsi:type) and AT(xsi:nil) productions, exclude them continue; } else { (*dest)->rule[i].part[partNum].prod[destProdIndx] = src->rule[i].part[partNum].prod[p]; destProdIndx++; } } (*dest)->rule[i].part[partNum].count = destProdIndx; (*dest)->rule[i].part[partNum].bits = getBitsNumber(destProdIndx - 1); } } /* The last rule is an empty rule with a single EE production */ (*dest)->rule[(*dest)->count - 1].part[0].prod = static_prod_empty_part0; (*dest)->rule[(*dest)->count - 1].part[0].bits = 0; (*dest)->rule[(*dest)->count - 1].part[0].count = 1; (*dest)->rule[(*dest)->count - 1].part[1].prod = NULL; (*dest)->rule[(*dest)->count - 1].part[1].bits = 0; (*dest)->rule[(*dest)->count - 1].part[1].count = 0; (*dest)->rule[(*dest)->count - 1].part[2].prod = NULL; (*dest)->rule[(*dest)->count - 1].part[2].bits = 0; (*dest)->rule[(*dest)->count - 1].part[2].count = 0; } else { // STRICT FALSE mode for(i = 0; i < (*dest)->count - 1; i++) { for(partNum = 0; partNum < 3; partNum++) { // Copy all productions in the rules less than contentIndex i.e. (*dest)->count - 1 // while taking into account that we do not need the Content2 index added during augmentation (*dest)->rule[i].part[partNum].prod = memManagedAllocate(&strm->memList, sizeof(Production)*(src->rule[i].part[partNum].count)); if((*dest)->rule[i].part[partNum].prod == NULL) return MEMORY_ALLOCATION_ERROR; destProdIndx = 0; for(p = 0; p < src->rule[i].part[partNum].count; p++) { if(src->rule[i].part[partNum].prod[p].eventType == EVENT_AT_ALL || src->rule[i].part[partNum].prod[p].eventType == EVENT_AT_QNAME || src->rule[i].part[partNum].prod[p].eventType == EVENT_AT_URI || src->rule[i].part[partNum].prod[p].eventType == EVENT_EE || (partNum > 0 && (src->rule[i].part[partNum].prod[p].eventType == EVENT_NS || src->rule[i].part[partNum].prod[p].eventType == EVENT_SC) ) ) { (*dest)->rule[i].part[partNum].prod[destProdIndx] = src->rule[i].part[partNum].prod[p]; destProdIndx++; } else if(partNum > 0 && (src->rule[i].part[partNum].prod[p].eventType == EVENT_SE_ALL || src->rule[i].part[partNum].prod[p].eventType == EVENT_CH || src->rule[i].part[partNum].prod[p].eventType == EVENT_ER || src->rule[i].part[partNum].prod[p].eventType == EVENT_CM || src->rule[i].part[partNum].prod[p].eventType == EVENT_PI)) { (*dest)->rule[i].part[partNum].prod[destProdIndx] = src->rule[i].part[partNum].prod[p]; (*dest)->rule[i].part[partNum].prod[destProdIndx].nonTermID = (*dest)->count - 1; destProdIndx++; } } (*dest)->rule[i].part[partNum].count = destProdIndx; } (*dest)->rule[i].part[0].bits = getBitsNumber((*dest)->rule[i].part[0].count - 1 + ((*dest)->rule[i].part[1].count > 0)); (*dest)->rule[i].part[1].bits = getBitsNumber((*dest)->rule[i].part[1].count - 1 + ((*dest)->rule[i].part[2].count > 0)); (*dest)->rule[i].part[2].bits = getBitsNumber((*dest)->rule[i].part[2].count - 1); } /* The last rule is: * * NT-contentIndex-1 : * EE 0 * SE (*) NT-contentIndex-1 1.0 * CH [untyped value] NT-contentIndex-1 1.1 * ER NT-contentIndex-1 1.2 * CM NT-contentIndex-1 1.3.0 * PI NT-contentIndex-1 1.3.1 * */ /* Part 1 */ (*dest)->rule[(*dest)->count - 1].part[0].prod = static_prod_empty_part0; (*dest)->rule[(*dest)->count - 1].part[0].bits = 1; (*dest)->rule[(*dest)->count - 1].part[0].count = 1; { /* Part 2 and 3 */ int part2count = 2; int part3count = 0; if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_DTD)) part2count++; if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_COMMENTS)) part3count++; if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_PIS)) part3count++; (*dest)->rule[(*dest)->count - 1].part[1].prod = memManagedAllocate(&strm->memList, sizeof(Production)*part2count); if((*dest)->rule[(*dest)->count - 1].part[1].prod == NULL) return MEMORY_ALLOCATION_ERROR; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-1].eventType = EVENT_SE_ALL; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-1].nonTermID = (*dest)->count - 1; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-1].typeId = INDEX_MAX; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-2].eventType = EVENT_CH; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-2].nonTermID = (*dest)->count - 1; (*dest)->rule[(*dest)->count - 1].part[1].prod[part2count-2].typeId = INDEX_MAX; if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_DTD)) { (*dest)->rule[(*dest)->count - 1].part[1].prod[0].eventType = EVENT_ER; (*dest)->rule[(*dest)->count - 1].part[1].prod[0].nonTermID = (*dest)->count - 1; (*dest)->rule[(*dest)->count - 1].part[1].prod[0].typeId = INDEX_MAX; } (*dest)->rule[(*dest)->count - 1].part[1].bits = getBitsNumber(part2count - 1 + (part3count > 0)); (*dest)->rule[(*dest)->count - 1].part[1].count = part2count; if(part3count > 0) { (*dest)->rule[(*dest)->count - 1].part[2].prod = memManagedAllocate(&strm->memList, sizeof(Production)*part3count); if((*dest)->rule[(*dest)->count - 1].part[2].prod == NULL) return MEMORY_ALLOCATION_ERROR; if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_COMMENTS)) { (*dest)->rule[(*dest)->count - 1].part[2].prod[part3count - 1].eventType = EVENT_CM; (*dest)->rule[(*dest)->count - 1].part[2].prod[part3count - 1].nonTermID = (*dest)->count - 1; (*dest)->rule[(*dest)->count - 1].part[2].prod[part3count - 1].typeId = INDEX_MAX; } if(IS_PRESENT(strm->header.opts.preserve, PRESERVE_PIS)) { (*dest)->rule[(*dest)->count - 1].part[2].prod[0].eventType = EVENT_PI; (*dest)->rule[(*dest)->count - 1].part[2].prod[0].nonTermID = (*dest)->count - 1; (*dest)->rule[(*dest)->count - 1].part[2].prod[0].typeId = INDEX_MAX; } (*dest)->rule[(*dest)->count - 1].part[2].bits = part3count > 1; (*dest)->rule[(*dest)->count - 1].part[2].count = part3count; } else { (*dest)->rule[(*dest)->count - 1].part[2].prod = NULL; (*dest)->rule[(*dest)->count - 1].part[2].bits = 0; (*dest)->rule[(*dest)->count - 1].part[2].count = 0; } } } #if DEBUG_GRAMMAR == ON { unsigned int r; DEBUG_MSG(INFO, DEBUG_GRAMMAR, (">Empty grammar:\n")); for(r = 0; r < (*dest)->count; r++) { if(printGrammarRule(r, &(*dest)->rule[r], strm->schema) != ERR_OK) DEBUG_MSG(INFO, DEBUG_GRAMMAR, (">Error printing grammar rule\n")); } } #endif return ERR_OK; }
void BX_CPU_C::long_mode_int(Bit8u vector, unsigned soft_int, bx_bool push_error, Bit16u error_code) { bx_descriptor_t gate_descriptor, cs_descriptor; bx_selector_t cs_selector; // interrupt vector must be within IDT table limits, // else #GP(vector*8 + 2 + EXT) if ((vector*16 + 15) > BX_CPU_THIS_PTR idtr.limit) { BX_ERROR(("interrupt(long mode): vector must be within IDT table limits, IDT.limit = 0x%x", BX_CPU_THIS_PTR idtr.limit)); exception(BX_GP_EXCEPTION, vector*8 + 2); } Bit64u desctmp1 = system_read_qword(BX_CPU_THIS_PTR idtr.base + vector*16); Bit64u desctmp2 = system_read_qword(BX_CPU_THIS_PTR idtr.base + vector*16 + 8); if (desctmp2 & BX_CONST64(0x00001F0000000000)) { BX_ERROR(("interrupt(long mode): IDT entry extended attributes DWORD4 TYPE != 0")); exception(BX_GP_EXCEPTION, vector*8 + 2); } Bit32u dword1 = GET32L(desctmp1); Bit32u dword2 = GET32H(desctmp1); Bit32u dword3 = GET32L(desctmp2); parse_descriptor(dword1, dword2, &gate_descriptor); if ((gate_descriptor.valid==0) || gate_descriptor.segment) { BX_ERROR(("interrupt(long mode): gate descriptor is not valid sys seg")); exception(BX_GP_EXCEPTION, vector*8 + 2); } // descriptor AR byte must indicate interrupt gate, trap gate, // or task gate, else #GP(vector*8 + 2 + EXT) if (gate_descriptor.type != BX_386_INTERRUPT_GATE && gate_descriptor.type != BX_386_TRAP_GATE) { BX_ERROR(("interrupt(long mode): unsupported gate type %u", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, vector*8 + 2); } // if software interrupt, then gate descripor DPL must be >= CPL, // else #GP(vector * 8 + 2 + EXT) if (soft_int && gate_descriptor.dpl < CPL) { BX_ERROR(("interrupt(long mode): soft_int && gate.dpl < CPL")); exception(BX_GP_EXCEPTION, vector*8 + 2); } // Gate must be present, else #NP(vector * 8 + 2 + EXT) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("interrupt(long mode): gate.p == 0")); exception(BX_NP_EXCEPTION, vector*8 + 2); } Bit16u gate_dest_selector = gate_descriptor.u.gate.dest_selector; Bit64u gate_dest_offset = ((Bit64u)dword3 << 32) | gate_descriptor.u.gate.dest_offset; unsigned ist = gate_descriptor.u.gate.param_count & 0x7; // examine CS selector and descriptor given in gate descriptor // selector must be non-null else #GP(EXT) if ((gate_dest_selector & 0xfffc) == 0) { BX_ERROR(("int_trap_gate(long mode): selector null")); exception(BX_GP_EXCEPTION, 0); } parse_selector(gate_dest_selector, &cs_selector); // selector must be within its descriptor table limits // else #GP(selector+EXT) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // descriptor AR byte must indicate code seg // and code segment descriptor DPL<=CPL, else #GP(selector+EXT) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type) || cs_descriptor.dpl > CPL) { BX_ERROR(("interrupt(long mode): not accessible or not code segment")); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } // check that it's a 64 bit segment if (! IS_LONG64_SEGMENT(cs_descriptor) || cs_descriptor.u.segment.d_b) { BX_ERROR(("interrupt(long mode): must be 64 bit segment")); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } // segment must be present, else #NP(selector + EXT) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("interrupt(long mode): segment not present")); exception(BX_NP_EXCEPTION, cs_selector.value & 0xfffc); } Bit64u RSP_for_cpl_x; Bit64u old_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; Bit64u old_RIP = RIP; Bit64u old_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; Bit64u old_RSP = RSP; // if code segment is non-conforming and DPL < CPL then // INTERRUPT TO INNER PRIVILEGE: if (IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && cs_descriptor.dpl < CPL) { BX_DEBUG(("interrupt(long mode): INTERRUPT TO INNER PRIVILEGE")); // check selector and descriptor for new stack in current TSS if (ist > 0) { BX_DEBUG(("interrupt(long mode): trap to IST, vector = %d", ist)); RSP_for_cpl_x = get_RSP_from_TSS(ist+3); } else { RSP_for_cpl_x = get_RSP_from_TSS(cs_descriptor.dpl); } // align stack RSP_for_cpl_x &= BX_CONST64(0xfffffffffffffff0); // push old stack long pointer onto new stack write_new_stack_qword_64(RSP_for_cpl_x - 8, cs_descriptor.dpl, old_SS); write_new_stack_qword_64(RSP_for_cpl_x - 16, cs_descriptor.dpl, old_RSP); write_new_stack_qword_64(RSP_for_cpl_x - 24, cs_descriptor.dpl, read_eflags()); // push long pointer to return address onto new stack write_new_stack_qword_64(RSP_for_cpl_x - 32, cs_descriptor.dpl, old_CS); write_new_stack_qword_64(RSP_for_cpl_x - 40, cs_descriptor.dpl, old_RIP); RSP_for_cpl_x -= 40; if (push_error) { RSP_for_cpl_x -= 8; write_new_stack_qword_64(RSP_for_cpl_x, cs_descriptor.dpl, error_code); } // load CS:RIP (guaranteed to be in 64 bit mode) branch_far64(&cs_selector, &cs_descriptor, gate_dest_offset, cs_descriptor.dpl); // set up null SS descriptor load_null_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], cs_descriptor.dpl); } else if(IS_CODE_SEGMENT_CONFORMING(cs_descriptor.type) || cs_descriptor.dpl==CPL) { // if code segment is conforming OR code segment DPL = CPL then // INTERRUPT TO SAME PRIVILEGE LEVEL: BX_DEBUG(("interrupt(long mode): INTERRUPT TO SAME PRIVILEGE")); // check selector and descriptor for new stack in current TSS if (ist > 0) { BX_DEBUG(("interrupt(long mode): trap to IST, vector = %d", ist)); RSP_for_cpl_x = get_RSP_from_TSS(ist+3); } else { RSP_for_cpl_x = RSP; } // align stack RSP_for_cpl_x &= BX_CONST64(0xfffffffffffffff0); // push flags onto stack // push current CS selector onto stack // push return offset onto stack write_new_stack_qword_64(RSP_for_cpl_x - 8, cs_descriptor.dpl, old_SS); write_new_stack_qword_64(RSP_for_cpl_x - 16, cs_descriptor.dpl, old_RSP); write_new_stack_qword_64(RSP_for_cpl_x - 24, cs_descriptor.dpl, read_eflags()); // push long pointer to return address onto new stack write_new_stack_qword_64(RSP_for_cpl_x - 32, cs_descriptor.dpl, old_CS); write_new_stack_qword_64(RSP_for_cpl_x - 40, cs_descriptor.dpl, old_RIP); RSP_for_cpl_x -= 40; if (push_error) { RSP_for_cpl_x -= 8; write_new_stack_qword_64(RSP_for_cpl_x, cs_descriptor.dpl, error_code); } // set the RPL field of CS to CPL branch_far64(&cs_selector, &cs_descriptor, gate_dest_offset, CPL); } else { BX_ERROR(("interrupt(long mode): bad descriptor type %u (CS.DPL=%u CPL=%u)", (unsigned) cs_descriptor.type, (unsigned) cs_descriptor.dpl, (unsigned) CPL)); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } RSP = RSP_for_cpl_x; // if interrupt gate then set IF to 0 if (!(gate_descriptor.type & 1)) // even is int-gate BX_CPU_THIS_PTR clear_IF(); BX_CPU_THIS_PTR clear_TF(); //BX_CPU_THIS_PTR clear_VM(); // VM is clear in long mode BX_CPU_THIS_PTR clear_RF(); BX_CPU_THIS_PTR clear_NT(); }
void BX_CPU_C::protected_mode_int(Bit8u vector, unsigned soft_int, bx_bool push_error, Bit16u error_code) { bx_descriptor_t gate_descriptor, cs_descriptor; bx_selector_t cs_selector; Bit16u raw_tss_selector; bx_selector_t tss_selector; bx_descriptor_t tss_descriptor; Bit16u gate_dest_selector; Bit32u gate_dest_offset; // interrupt vector must be within IDT table limits, // else #GP(vector*8 + 2 + EXT) if ((vector*8 + 7) > BX_CPU_THIS_PTR idtr.limit) { BX_ERROR(("interrupt(): vector must be within IDT table limits, IDT.limit = 0x%x", BX_CPU_THIS_PTR idtr.limit)); exception(BX_GP_EXCEPTION, vector*8 + 2); } Bit64u desctmp = system_read_qword(BX_CPU_THIS_PTR idtr.base + vector*8); Bit32u dword1 = GET32L(desctmp); Bit32u dword2 = GET32H(desctmp); parse_descriptor(dword1, dword2, &gate_descriptor); if ((gate_descriptor.valid==0) || gate_descriptor.segment) { BX_ERROR(("interrupt(): gate descriptor is not valid sys seg (vector=0x%02x)", vector)); exception(BX_GP_EXCEPTION, vector*8 + 2); } // descriptor AR byte must indicate interrupt gate, trap gate, // or task gate, else #GP(vector*8 + 2 + EXT) switch (gate_descriptor.type) { case BX_TASK_GATE: case BX_286_INTERRUPT_GATE: case BX_286_TRAP_GATE: case BX_386_INTERRUPT_GATE: case BX_386_TRAP_GATE: break; default: BX_ERROR(("interrupt(): gate.type(%u) != {5,6,7,14,15}", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, vector*8 + 2); } // if software interrupt, then gate descripor DPL must be >= CPL, // else #GP(vector * 8 + 2 + EXT) if (soft_int && gate_descriptor.dpl < CPL) { BX_ERROR(("interrupt(): soft_int && (gate.dpl < CPL)")); exception(BX_GP_EXCEPTION, vector*8 + 2); } // Gate must be present, else #NP(vector * 8 + 2 + EXT) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("interrupt(): gate not present")); exception(BX_NP_EXCEPTION, vector*8 + 2); } switch (gate_descriptor.type) { case BX_TASK_GATE: // examine selector to TSS, given in task gate descriptor raw_tss_selector = gate_descriptor.u.taskgate.tss_selector; parse_selector(raw_tss_selector, &tss_selector); // must specify global in the local/global bit, // else #GP(TSS selector) if (tss_selector.ti) { BX_ERROR(("interrupt(): tss_selector.ti=1 from gate descriptor - #GP(tss_selector)")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc); } // index must be within GDT limits, else #TS(TSS selector) fetch_raw_descriptor(&tss_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &tss_descriptor); // AR byte must specify available TSS, // else #GP(TSS selector) if (tss_descriptor.valid==0 || tss_descriptor.segment) { BX_ERROR(("interrupt(): TSS selector points to invalid or bad TSS - #GP(tss_selector)")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc); } if (tss_descriptor.type!=BX_SYS_SEGMENT_AVAIL_286_TSS && tss_descriptor.type!=BX_SYS_SEGMENT_AVAIL_386_TSS) { BX_ERROR(("interrupt(): TSS selector points to bad TSS - #GP(tss_selector)")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc); } // TSS must be present, else #NP(TSS selector) if (! IS_PRESENT(tss_descriptor)) { BX_ERROR(("interrupt(): TSS descriptor.p == 0")); exception(BX_NP_EXCEPTION, raw_tss_selector & 0xfffc); } // switch tasks with nesting to TSS task_switch(0, &tss_selector, &tss_descriptor, BX_TASK_FROM_INT, dword1, dword2); RSP_SPECULATIVE; // if interrupt was caused by fault with error code // stack limits must allow push of 2 more bytes, else #SS(0) // push error code onto stack if (push_error) { if (tss_descriptor.type >= 9) // TSS386 push_32(error_code); else push_16(error_code); } // instruction pointer must be in CS limit, else #GP(0) if (EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) { BX_ERROR(("interrupt(): EIP > CS.limit")); exception(BX_GP_EXCEPTION, 0); } RSP_COMMIT; return; case BX_286_INTERRUPT_GATE: case BX_286_TRAP_GATE: case BX_386_INTERRUPT_GATE: case BX_386_TRAP_GATE: gate_dest_selector = gate_descriptor.u.gate.dest_selector; gate_dest_offset = gate_descriptor.u.gate.dest_offset; // examine CS selector and descriptor given in gate descriptor // selector must be non-null else #GP(EXT) if ((gate_dest_selector & 0xfffc) == 0) { BX_ERROR(("int_trap_gate(): selector null")); exception(BX_GP_EXCEPTION, 0); } parse_selector(gate_dest_selector, &cs_selector); // selector must be within its descriptor table limits // else #GP(selector+EXT) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // descriptor AR byte must indicate code seg // and code segment descriptor DPL<=CPL, else #GP(selector+EXT) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type) || cs_descriptor.dpl > CPL) { BX_ERROR(("interrupt(): not accessible or not code segment cs=0x%04x", cs_selector.value)); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } // segment must be present, else #NP(selector + EXT) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("interrupt(): segment not present")); exception(BX_NP_EXCEPTION, cs_selector.value & 0xfffc); } // if code segment is non-conforming and DPL < CPL then // INTERRUPT TO INNER PRIVILEGE if(IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && cs_descriptor.dpl < CPL) { Bit16u old_SS, old_CS, SS_for_cpl_x; Bit32u ESP_for_cpl_x, old_EIP, old_ESP; bx_descriptor_t ss_descriptor; bx_selector_t ss_selector; int is_v8086_mode = v8086_mode(); BX_DEBUG(("interrupt(): INTERRUPT TO INNER PRIVILEGE")); // check selector and descriptor for new stack in current TSS get_SS_ESP_from_TSS(cs_descriptor.dpl, &SS_for_cpl_x, &ESP_for_cpl_x); if (is_v8086_mode && cs_descriptor.dpl != 0) { // if code segment DPL != 0 then #GP(new code segment selector) BX_ERROR(("interrupt(): code segment DPL(%d) != 0 in v8086 mode", cs_descriptor.dpl)); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } // Selector must be non-null else #TS(EXT) if ((SS_for_cpl_x & 0xfffc) == 0) { BX_ERROR(("interrupt(): SS selector null")); exception(BX_TS_EXCEPTION, 0); /* TS(ext) */ } // selector index must be within its descriptor table limits // else #TS(SS selector + EXT) parse_selector(SS_for_cpl_x, &ss_selector); // fetch 2 dwords of descriptor; call handles out of limits checks fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_TS_EXCEPTION); parse_descriptor(dword1, dword2, &ss_descriptor); // selector rpl must = dpl of code segment, // else #TS(SS selector + ext) if (ss_selector.rpl != cs_descriptor.dpl) { BX_ERROR(("interrupt(): SS.rpl != CS.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // stack seg DPL must = DPL of code segment, // else #TS(SS selector + ext) if (ss_descriptor.dpl != cs_descriptor.dpl) { BX_ERROR(("interrupt(): SS.dpl != CS.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // descriptor must indicate writable data segment, // else #TS(SS selector + EXT) if (ss_descriptor.valid==0 || ss_descriptor.segment==0 || IS_CODE_SEGMENT(ss_descriptor.type) || !IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type)) { BX_ERROR(("interrupt(): SS is not writable data segment")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // seg must be present, else #SS(SS selector + ext) if (! IS_PRESENT(ss_descriptor)) { BX_ERROR(("interrupt(): SS not present")); exception(BX_SS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // IP must be within CS segment boundaries, else #GP(0) if (gate_dest_offset > cs_descriptor.u.segment.limit_scaled) { BX_ERROR(("interrupt(): gate EIP > CS.limit")); exception(BX_GP_EXCEPTION, 0); } old_ESP = ESP; old_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; old_EIP = EIP; old_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; // Prepare new stack segment bx_segment_reg_t new_stack; new_stack.selector = ss_selector; new_stack.cache = ss_descriptor; new_stack.selector.rpl = cs_descriptor.dpl; // add cpl to the selector value new_stack.selector.value = (0xfffc & new_stack.selector.value) | new_stack.selector.rpl; if (ss_descriptor.u.segment.d_b) { Bit32u temp_ESP = ESP_for_cpl_x; if (is_v8086_mode) { if (gate_descriptor.type>=14) { // 386 int/trap gate write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value); write_new_stack_dword_32(&new_stack, temp_ESP-12, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value); write_new_stack_dword_32(&new_stack, temp_ESP-16, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value); temp_ESP -= 16; } else { write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value); write_new_stack_word_32(&new_stack, temp_ESP-6, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value); write_new_stack_word_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value); temp_ESP -= 8; } } if (gate_descriptor.type>=14) { // 386 int/trap gate // push long pointer to old stack onto new stack write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, old_SS); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, old_ESP); write_new_stack_dword_32(&new_stack, temp_ESP-12, cs_descriptor.dpl, read_eflags()); write_new_stack_dword_32(&new_stack, temp_ESP-16, cs_descriptor.dpl, old_CS); write_new_stack_dword_32(&new_stack, temp_ESP-20, cs_descriptor.dpl, old_EIP); temp_ESP -= 20; if (push_error) { temp_ESP -= 4; write_new_stack_dword_32(&new_stack, temp_ESP, cs_descriptor.dpl, error_code); } } else { // 286 int/trap gate // push long pointer to old stack onto new stack write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, old_SS); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, (Bit16u) old_ESP); write_new_stack_word_32(&new_stack, temp_ESP-6, cs_descriptor.dpl, (Bit16u) read_eflags()); write_new_stack_word_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, old_CS); write_new_stack_word_32(&new_stack, temp_ESP-10, cs_descriptor.dpl, (Bit16u) old_EIP); temp_ESP -= 10; if (push_error) { temp_ESP -= 2; write_new_stack_word_32(&new_stack, temp_ESP, cs_descriptor.dpl, error_code); } } ESP = temp_ESP; } else { Bit16u temp_SP = (Bit16u) ESP_for_cpl_x; if (is_v8086_mode) { if (gate_descriptor.type>=14) { // 386 int/trap gate write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-12), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-16), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value); temp_SP -= 16; } else { write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-6), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value); temp_SP -= 8; } } if (gate_descriptor.type>=14) { // 386 int/trap gate // push long pointer to old stack onto new stack write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, old_SS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, old_ESP); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-12), cs_descriptor.dpl, read_eflags()); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-16), cs_descriptor.dpl, old_CS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-20), cs_descriptor.dpl, old_EIP); temp_SP -= 20; if (push_error) { temp_SP -= 4; write_new_stack_dword_32(&new_stack, temp_SP, cs_descriptor.dpl, error_code); } } else { // 286 int/trap gate // push long pointer to old stack onto new stack write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, old_SS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, (Bit16u) old_ESP); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-6), cs_descriptor.dpl, (Bit16u) read_eflags()); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, old_CS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-10), cs_descriptor.dpl, (Bit16u) old_EIP); temp_SP -= 10; if (push_error) { temp_SP -= 2; write_new_stack_word_32(&new_stack, temp_SP, cs_descriptor.dpl, error_code); } } SP = temp_SP; } // load new CS:eIP values from gate // set CPL to new code segment DPL // set RPL of CS to CPL load_cs(&cs_selector, &cs_descriptor, cs_descriptor.dpl); // load new SS:eSP values from TSS load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl); if (is_v8086_mode) { BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value = 0; } } else { BX_DEBUG(("interrupt(): INTERRUPT TO SAME PRIVILEGE")); if (v8086_mode() && (IS_CODE_SEGMENT_CONFORMING(cs_descriptor.type) || cs_descriptor.dpl != 0)) { // if code segment DPL != 0 then #GP(new code segment selector) BX_ERROR(("interrupt(): code segment conforming or DPL(%d) != 0 in v8086 mode", cs_descriptor.dpl)); exception(BX_GP_EXCEPTION, cs_selector.value & 0xfffc); } // EIP must be in CS limit else #GP(0) if (gate_dest_offset > cs_descriptor.u.segment.limit_scaled) { BX_ERROR(("interrupt(): IP > CS descriptor limit")); exception(BX_GP_EXCEPTION, 0); } // push flags onto stack // push current CS selector onto stack // push return offset onto stack if (gate_descriptor.type >= 14) { // 386 gate push_32(read_eflags()); push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_32(EIP); if (push_error) push_32(error_code); } else { // 286 gate push_16((Bit16u) read_eflags()); push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_16(IP); if (push_error) push_16(error_code); } // load CS:IP from gate // load CS descriptor // set the RPL field of CS to CPL load_cs(&cs_selector, &cs_descriptor, CPL); } EIP = gate_dest_offset; // if interrupt gate then set IF to 0 if (!(gate_descriptor.type & 1)) // even is int-gate BX_CPU_THIS_PTR clear_IF(); BX_CPU_THIS_PTR clear_TF(); BX_CPU_THIS_PTR clear_NT(); BX_CPU_THIS_PTR clear_VM(); BX_CPU_THIS_PTR clear_RF(); return; default: BX_PANIC(("bad descriptor type in interrupt()!")); break; } }
BX_CPU_C::return_protected(bxInstruction_c *i, Bit16u pop_bytes) { Bit16u raw_cs_selector, raw_ss_selector; bx_selector_t cs_selector, ss_selector; bx_descriptor_t cs_descriptor, ss_descriptor; Bit32u stack_param_offset; bx_address return_RIP, return_RSP, temp_RSP; Bit32u dword1, dword2; /* + 6+N*2: SS | +12+N*4: SS | +24+N*8 SS */ /* + 4+N*2: SP | + 8+N*4: ESP | +16+N*8 RSP */ /* parm N | + parm N | + parm N */ /* parm 3 | + parm 3 | + parm 3 */ /* parm 2 | + parm 2 | + parm 2 */ /* + 4: parm 1 | + 8: parm 1 | +16: parm 1 */ /* + 2: CS | + 4: CS | + 8: CS */ /* + 0: IP | + 0: EIP | + 0: RIP */ #if BX_SUPPORT_X86_64 if (StackAddrSize64()) temp_RSP = RSP; else #endif { if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) temp_RSP = ESP; else temp_RSP = SP; } #if BX_SUPPORT_X86_64 if (i->os64L()) { raw_cs_selector = (Bit16u) read_virtual_qword_64(BX_SEG_REG_SS, temp_RSP + 8); return_RIP = read_virtual_qword_64(BX_SEG_REG_SS, temp_RSP); stack_param_offset = 16; } else #endif if (i->os32L()) { raw_cs_selector = (Bit16u) read_virtual_dword(BX_SEG_REG_SS, temp_RSP + 4); return_RIP = read_virtual_dword(BX_SEG_REG_SS, temp_RSP); stack_param_offset = 8; } else { raw_cs_selector = read_virtual_word(BX_SEG_REG_SS, temp_RSP + 2); return_RIP = read_virtual_word(BX_SEG_REG_SS, temp_RSP); stack_param_offset = 4; } // selector must be non-null else #GP(0) if ((raw_cs_selector & 0xfffc) == 0) { BX_ERROR(("return_protected: CS selector null")); exception(BX_GP_EXCEPTION, 0, 0); } parse_selector(raw_cs_selector, &cs_selector); // selector index must be within its descriptor table limits, // else #GP(selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); // descriptor AR byte must indicate code segment, else #GP(selector) parse_descriptor(dword1, dword2, &cs_descriptor); // return selector RPL must be >= CPL, else #GP(return selector) if (cs_selector.rpl < CPL) { BX_ERROR(("return_protected: CS.rpl < CPL")); exception(BX_GP_EXCEPTION, raw_cs_selector & 0xfffc, 0); } // check code-segment descriptor check_cs(&cs_descriptor, raw_cs_selector, 0, cs_selector.rpl); // if return selector RPL == CPL then // RETURN TO SAME PRIVILEGE LEVEL if (cs_selector.rpl == CPL) { BX_DEBUG(("return_protected: return to SAME PRIVILEGE LEVEL")); branch_far64(&cs_selector, &cs_descriptor, return_RIP, CPL); #if BX_SUPPORT_X86_64 if (StackAddrSize64()) RSP += stack_param_offset + pop_bytes; else #endif { if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) RSP = ESP + stack_param_offset + pop_bytes; else SP += stack_param_offset + pop_bytes; } return; } /* RETURN TO OUTER PRIVILEGE LEVEL */ else { /* + 6+N*2: SS | +12+N*4: SS | +24+N*8 SS */ /* + 4+N*2: SP | + 8+N*4: ESP | +16+N*8 RSP */ /* parm N | + parm N | + parm N */ /* parm 3 | + parm 3 | + parm 3 */ /* parm 2 | + parm 2 | + parm 2 */ /* + 4: parm 1 | + 8: parm 1 | +16: parm 1 */ /* + 2: CS | + 4: CS | + 8: CS */ /* + 0: IP | + 0: EIP | + 0: RIP */ BX_DEBUG(("return_protected: return to OUTER PRIVILEGE LEVEL")); #if BX_SUPPORT_X86_64 if (i->os64L()) { raw_ss_selector = read_virtual_word_64 (BX_SEG_REG_SS, temp_RSP + 24 + pop_bytes); return_RSP = read_virtual_qword_64(BX_SEG_REG_SS, temp_RSP + 16 + pop_bytes); } else #endif if (i->os32L()) { raw_ss_selector = read_virtual_word (BX_SEG_REG_SS, temp_RSP + 12 + pop_bytes); return_RSP = read_virtual_dword(BX_SEG_REG_SS, temp_RSP + 8 + pop_bytes); } else { raw_ss_selector = read_virtual_word(BX_SEG_REG_SS, temp_RSP + 6 + pop_bytes); return_RSP = read_virtual_word(BX_SEG_REG_SS, temp_RSP + 4 + pop_bytes); } /* selector index must be within its descriptor table limits, * else #GP(selector) */ parse_selector(raw_ss_selector, &ss_selector); if ((raw_ss_selector & 0xfffc) == 0) { if (long_mode()) { if (! IS_LONG64_SEGMENT(cs_descriptor) || (cs_selector.rpl == 3)) { BX_ERROR(("return_protected: SS selector null")); exception(BX_GP_EXCEPTION, 0, 0); } } else // not in long or compatibility mode { BX_ERROR(("return_protected: SS selector null")); exception(BX_GP_EXCEPTION, 0, 0); } } fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &ss_descriptor); /* selector RPL must = RPL of the return CS selector, * else #GP(selector) */ if (ss_selector.rpl != cs_selector.rpl) { BX_ERROR(("return_protected: ss.rpl != cs.rpl")); exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0); } /* descriptor AR byte must indicate a writable data segment, * else #GP(selector) */ if (ss_descriptor.valid==0 || ss_descriptor.segment==0 || IS_CODE_SEGMENT(ss_descriptor.type) || !IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type)) { BX_ERROR(("return_protected: SS.AR byte not writable data")); exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0); } /* descriptor dpl must = RPL of the return CS selector, * else #GP(selector) */ if (ss_descriptor.dpl != cs_selector.rpl) { BX_ERROR(("return_protected: SS.dpl != cs.rpl")); exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0); } /* segment must be present else #SS(selector) */ if (! IS_PRESENT(ss_descriptor)) { BX_ERROR(("return_protected: ss.present == 0")); exception(BX_SS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } branch_far64(&cs_selector, &cs_descriptor, return_RIP, cs_selector.rpl); /* load SS:SP from stack */ /* load SS-cache with return SS descriptor */ load_ss(&ss_selector, &ss_descriptor, cs_selector.rpl); #if BX_SUPPORT_X86_64 if (StackAddrSize64()) RSP = return_RSP + pop_bytes; else #endif if (ss_descriptor.u.segment.d_b) RSP = (Bit32u) return_RSP + pop_bytes; else SP = (Bit16u) return_RSP + pop_bytes; /* check ES, DS, FS, GS for validity */ validate_seg_regs(); } }
static errorCode sample_dateTimeData(EXIPDateTime dt_val, void* app_data) { struct appData* appD = (struct appData*) app_data; char fsecBuf[30]; int i; if(IS_PRESENT(dt_val.presenceMask, FRACT_PRESENCE)) { unsigned int tmpfValue = dt_val.fSecs.value; int digitNum = 0; fsecBuf[0] = '.'; while(tmpfValue) { digitNum++; tmpfValue = tmpfValue / 10; } for(i = 0; i < dt_val.fSecs.offset + 1 - digitNum; i++) fsecBuf[1+i] = '0'; sprintf(fsecBuf + 1 + i, "%d", dt_val.fSecs.value); } else { fsecBuf[0] = '\0'; } if(appD->outputFormat == OUT_EXI) { if(appD->expectAttributeData) { printf("%04d-%02d-%02dT%02d:%02d:%02d%s", dt_val.dateTime.tm_year + 1900, dt_val.dateTime.tm_mon + 1, dt_val.dateTime.tm_mday, dt_val.dateTime.tm_hour, dt_val.dateTime.tm_min, dt_val.dateTime.tm_sec, fsecBuf); printf("\"\n"); appD->expectAttributeData = 0; } else { printf("CH "); printf("%04d-%02d-%02dT%02d:%02d:%02d%s", dt_val.dateTime.tm_year + 1900, dt_val.dateTime.tm_mon + 1, dt_val.dateTime.tm_mday, dt_val.dateTime.tm_hour, dt_val.dateTime.tm_min, dt_val.dateTime.tm_sec, fsecBuf); printf("\n"); } } else if(appD->outputFormat == OUT_XML) { if(appD->expectAttributeData) { printf("%04d-%02d-%02dT%02d:%02d:%02d%s", dt_val.dateTime.tm_year + 1900, dt_val.dateTime.tm_mon + 1, dt_val.dateTime.tm_mday, dt_val.dateTime.tm_hour, dt_val.dateTime.tm_min, dt_val.dateTime.tm_sec, fsecBuf); printf("\""); appD->expectAttributeData = 0; } else { if(appD->unclosedElement) printf(">"); appD->unclosedElement = 0; printf("%04d-%02d-%02dT%02d:%02d:%02d%s", dt_val.dateTime.tm_year + 1900, dt_val.dateTime.tm_mon + 1, dt_val.dateTime.tm_mday, dt_val.dateTime.tm_hour, dt_val.dateTime.tm_min, dt_val.dateTime.tm_sec, fsecBuf); } } return ERR_OK; }
void BX_CPU_C::task_switch(bx_selector_t *tss_selector, bx_descriptor_t *tss_descriptor, unsigned source, Bit32u dword1, Bit32u dword2) { Bit32u obase32; // base address of old TSS Bit32u nbase32; // base address of new TSS Bit32u temp32, newCR3; Bit16u raw_cs_selector, raw_ss_selector, raw_ds_selector, raw_es_selector, raw_fs_selector, raw_gs_selector, raw_ldt_selector; Bit16u temp16, trap_word; bx_selector_t cs_selector, ss_selector, ds_selector, es_selector, fs_selector, gs_selector, ldt_selector; bx_descriptor_t cs_descriptor, ss_descriptor, ldt_descriptor; Bit32u old_TSS_max, new_TSS_max, old_TSS_limit, new_TSS_limit; Bit32u newEAX, newECX, newEDX, newEBX; Bit32u newESP, newEBP, newESI, newEDI; Bit32u newEFLAGS, newEIP; BX_DEBUG(("TASKING: ENTER")); invalidate_prefetch_q(); // Discard any traps and inhibits for new context; traps will // resume upon return. BX_CPU_THIS_PTR debug_trap = 0; BX_CPU_THIS_PTR inhibit_mask = 0; // STEP 1: The following checks are made before calling task_switch(), // for JMP & CALL only. These checks are NOT made for exceptions, // interrupts & IRET. // // 1) TSS DPL must be >= CPL // 2) TSS DPL must be >= TSS selector RPL // 3) TSS descriptor is not busy. // TSS must be present, else #NP(TSS selector) if (tss_descriptor->p==0) { BX_ERROR(("task_switch: TSS descriptor is not present !")); exception(BX_NP_EXCEPTION, tss_selector->value & 0xfffc, 0); } // STEP 2: The processor performs limit-checking on the target TSS // to verify that the TSS limit is greater than or equal // to 67h (2Bh for 16-bit TSS). // Gather info about old TSS if (BX_CPU_THIS_PTR tr.cache.type <= 3) { old_TSS_max = 0x29; } else { old_TSS_max = 0x5F; } // Gather info about new TSS if (tss_descriptor->type <= 3) { // {1,3} new_TSS_max = 0x2B; } else { // tss_descriptor->type = {9,11} new_TSS_max = 0x67; } obase32 = (Bit32u) BX_CPU_THIS_PTR tr.cache.u.system.base; // old TSS.base old_TSS_limit = BX_CPU_THIS_PTR tr.cache.u.system.limit_scaled; nbase32 = (Bit32u) tss_descriptor->u.system.base; // new TSS.base new_TSS_limit = tss_descriptor->u.system.limit_scaled; // TSS must have valid limit, else #TS(TSS selector) if (tss_selector->ti || tss_descriptor->valid==0 || new_TSS_limit < new_TSS_max) { BX_ERROR(("task_switch(): new TSS limit < %d", new_TSS_max)); exception(BX_TS_EXCEPTION, tss_selector->value & 0xfffc, 0); } if (old_TSS_limit < old_TSS_max) { BX_ERROR(("task_switch(): old TSS limit < %d", old_TSS_max)); exception(BX_TS_EXCEPTION, BX_CPU_THIS_PTR tr.selector.value & 0xfffc, 0); } if (obase32 == nbase32) { BX_INFO(("TASK SWITCH: switching to the same TSS !")); } // Check that old TSS, new TSS, and all segment descriptors // used in the task switch are paged in. if (BX_CPU_THIS_PTR cr0.get_PG()) { dtranslate_linear(obase32, 0, BX_WRITE); // new TSS dtranslate_linear(obase32 + old_TSS_max, 0, BX_WRITE); dtranslate_linear(nbase32, 0, BX_READ); // old TSS dtranslate_linear(nbase32 + new_TSS_max, 0, BX_READ); // ??? Humm, we check the new TSS region with READ above, // but sometimes we need to write the link field in that // region. We also sometimes update other fields, perhaps // we need to WRITE check them here also, so that we keep // the written state consistent (ie, we don't encounter a // page fault in the middle). if (source == BX_TASK_FROM_CALL_OR_INT) { dtranslate_linear(nbase32, 0, BX_WRITE); dtranslate_linear(nbase32 + 2, 0, BX_WRITE); } } // Privilege and busy checks done in CALL, JUMP, INT, IRET // STEP 3: Save the current task state in the TSS. Up to this point, // any exception that occurs aborts the task switch without // changing the processor state. /* save current machine state in old task's TSS */ Bit32u oldEFLAGS = read_eflags(); /* if moving to busy task, clear NT bit */ if (tss_descriptor->type == BX_SYS_SEGMENT_BUSY_286_TSS || tss_descriptor->type == BX_SYS_SEGMENT_BUSY_386_TSS) { oldEFLAGS &= ~EFlagsNTMask; } if (BX_CPU_THIS_PTR tr.cache.type <= 3) { temp16 = IP; access_write_linear(Bit32u(obase32 + 14), 2, 0, &temp16); temp16 = oldEFLAGS; access_write_linear(Bit32u(obase32 + 16), 2, 0, &temp16); temp16 = AX; access_write_linear(Bit32u(obase32 + 18), 2, 0, &temp16); temp16 = CX; access_write_linear(Bit32u(obase32 + 20), 2, 0, &temp16); temp16 = DX; access_write_linear(Bit32u(obase32 + 22), 2, 0, &temp16); temp16 = BX; access_write_linear(Bit32u(obase32 + 24), 2, 0, &temp16); temp16 = SP; access_write_linear(Bit32u(obase32 + 26), 2, 0, &temp16); temp16 = BP; access_write_linear(Bit32u(obase32 + 28), 2, 0, &temp16); temp16 = SI; access_write_linear(Bit32u(obase32 + 30), 2, 0, &temp16); temp16 = DI; access_write_linear(Bit32u(obase32 + 32), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value; access_write_linear(Bit32u(obase32 + 34), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; access_write_linear(Bit32u(obase32 + 36), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; access_write_linear(Bit32u(obase32 + 38), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value; access_write_linear(Bit32u(obase32 + 40), 2, 0, &temp16); } else { temp32 = EIP; access_write_linear(Bit32u(obase32 + 0x20), 4, 0, &temp32); temp32 = oldEFLAGS; access_write_linear(Bit32u(obase32 + 0x24), 4, 0, &temp32); temp32 = EAX; access_write_linear(Bit32u(obase32 + 0x28), 4, 0, &temp32); temp32 = ECX; access_write_linear(Bit32u(obase32 + 0x2c), 4, 0, &temp32); temp32 = EDX; access_write_linear(Bit32u(obase32 + 0x30), 4, 0, &temp32); temp32 = EBX; access_write_linear(Bit32u(obase32 + 0x34), 4, 0, &temp32); temp32 = ESP; access_write_linear(Bit32u(obase32 + 0x38), 4, 0, &temp32); temp32 = EBP; access_write_linear(Bit32u(obase32 + 0x3c), 4, 0, &temp32); temp32 = ESI; access_write_linear(Bit32u(obase32 + 0x40), 4, 0, &temp32); temp32 = EDI; access_write_linear(Bit32u(obase32 + 0x44), 4, 0, &temp32); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value; access_write_linear(Bit32u(obase32 + 0x48), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; access_write_linear(Bit32u(obase32 + 0x4c), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; access_write_linear(Bit32u(obase32 + 0x50), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value; access_write_linear(Bit32u(obase32 + 0x54), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value; access_write_linear(Bit32u(obase32 + 0x58), 2, 0, &temp16); temp16 = BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value; access_write_linear(Bit32u(obase32 + 0x5c), 2, 0, &temp16); } // effect on link field of new task if (source == BX_TASK_FROM_CALL_OR_INT) { // set to selector of old task's TSS temp16 = BX_CPU_THIS_PTR tr.selector.value; access_write_linear(nbase32, 2, 0, &temp16); } // STEP 4: The new-task state is loaded from the TSS if (tss_descriptor->type <= 3) { access_read_linear(Bit32u(nbase32 + 14), 2, 0, BX_READ, &temp16); newEIP = temp16; // zero out upper word access_read_linear(Bit32u(nbase32 + 16), 2, 0, BX_READ, &temp16); newEFLAGS = temp16; // incoming TSS is 16bit: // - upper word of general registers is set to 0xFFFF // - upper word of eflags is zero'd // - FS, GS are zero'd // - upper word of eIP is zero'd access_read_linear(Bit32u(nbase32 + 18), 2, 0, BX_READ, &temp16); newEAX = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 20), 2, 0, BX_READ, &temp16); newECX = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 22), 2, 0, BX_READ, &temp16); newEDX = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 24), 2, 0, BX_READ, &temp16); newEBX = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 26), 2, 0, BX_READ, &temp16); newESP = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 28), 2, 0, BX_READ, &temp16); newEBP = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 30), 2, 0, BX_READ, &temp16); newESI = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 32), 2, 0, BX_READ, &temp16); newEDI = 0xffff0000 | temp16; access_read_linear(Bit32u(nbase32 + 34), 2, 0, BX_READ, &raw_es_selector); access_read_linear(Bit32u(nbase32 + 36), 2, 0, BX_READ, &raw_cs_selector); access_read_linear(Bit32u(nbase32 + 38), 2, 0, BX_READ, &raw_ss_selector); access_read_linear(Bit32u(nbase32 + 40), 2, 0, BX_READ, &raw_ds_selector); access_read_linear(Bit32u(nbase32 + 42), 2, 0, BX_READ, &raw_ldt_selector); raw_fs_selector = 0; // use a NULL selector raw_gs_selector = 0; // use a NULL selector // No CR3 change for 286 task switch newCR3 = 0; // keep compiler happy (not used) trap_word = 0; // keep compiler happy (not used) } else { if (BX_CPU_THIS_PTR cr0.get_PG()) access_read_linear(Bit32u(nbase32 + 0x1c), 4, 0, BX_READ, &newCR3); else newCR3 = 0; // keep compiler happy (not used) access_read_linear(Bit32u(nbase32 + 0x20), 4, 0, BX_READ, &newEIP); access_read_linear(Bit32u(nbase32 + 0x24), 4, 0, BX_READ, &newEFLAGS); access_read_linear(Bit32u(nbase32 + 0x28), 4, 0, BX_READ, &newEAX); access_read_linear(Bit32u(nbase32 + 0x2c), 4, 0, BX_READ, &newECX); access_read_linear(Bit32u(nbase32 + 0x30), 4, 0, BX_READ, &newEDX); access_read_linear(Bit32u(nbase32 + 0x34), 4, 0, BX_READ, &newEBX); access_read_linear(Bit32u(nbase32 + 0x38), 4, 0, BX_READ, &newESP); access_read_linear(Bit32u(nbase32 + 0x3c), 4, 0, BX_READ, &newEBP); access_read_linear(Bit32u(nbase32 + 0x40), 4, 0, BX_READ, &newESI); access_read_linear(Bit32u(nbase32 + 0x44), 4, 0, BX_READ, &newEDI); access_read_linear(Bit32u(nbase32 + 0x48), 2, 0, BX_READ, &raw_es_selector); access_read_linear(Bit32u(nbase32 + 0x4c), 2, 0, BX_READ, &raw_cs_selector); access_read_linear(Bit32u(nbase32 + 0x50), 2, 0, BX_READ, &raw_ss_selector); access_read_linear(Bit32u(nbase32 + 0x54), 2, 0, BX_READ, &raw_ds_selector); access_read_linear(Bit32u(nbase32 + 0x58), 2, 0, BX_READ, &raw_fs_selector); access_read_linear(Bit32u(nbase32 + 0x5c), 2, 0, BX_READ, &raw_gs_selector); access_read_linear(Bit32u(nbase32 + 0x60), 2, 0, BX_READ, &raw_ldt_selector); access_read_linear(Bit32u(nbase32 + 0x64), 2, 0, BX_READ, &trap_word); } // Step 5: If CALL, interrupt, or JMP, set busy flag in new task's // TSS descriptor. If IRET, leave set. if (source == BX_TASK_FROM_JUMP || source == BX_TASK_FROM_CALL_OR_INT) { // set the new task's busy bit Bit32u laddr = (Bit32u)(BX_CPU_THIS_PTR gdtr.base) + (tss_selector->index<<3) + 4; access_read_linear(laddr, 4, 0, BX_READ, &dword2); dword2 |= 0x200; access_write_linear(laddr, 4, 0, &dword2); } // Step 6: If JMP or IRET, clear busy bit in old task TSS descriptor, // otherwise leave set. // effect on Busy bit of old task if (source == BX_TASK_FROM_JUMP || source == BX_TASK_FROM_IRET) { // Bit is cleared Bit32u laddr = (Bit32u) BX_CPU_THIS_PTR gdtr.base + (BX_CPU_THIS_PTR tr.selector.index<<3) + 4; access_read_linear(laddr, 4, 0, BX_READ, &temp32); temp32 &= ~0x200; access_write_linear(laddr, 4, 0, &temp32); } // // Commit point. At this point, we commit to the new // context. If an unrecoverable error occurs in further // processing, we complete the task switch without performing // additional access and segment availablility checks and // generate the appropriate exception prior to beginning // execution of the new task. // // Step 7: Load the task register with the segment selector and // descriptor for the new task TSS. BX_CPU_THIS_PTR tr.selector = *tss_selector; BX_CPU_THIS_PTR tr.cache = *tss_descriptor; BX_CPU_THIS_PTR tr.cache.type |= 2; // mark TSS in TR as busy // Step 8: Set TS flag in the CR0 image stored in the new task TSS. BX_CPU_THIS_PTR cr0.set_TS(1); // Task switch clears LE/L3/L2/L1/L0 in DR7 BX_CPU_THIS_PTR dr7 &= ~0x00000155; // Step 9: If call or interrupt, set the NT flag in the eflags // image stored in new task's TSS. If IRET or JMP, // NT is restored from new TSS eflags image. (no change) // effect on NT flag of new task if (source == BX_TASK_FROM_CALL_OR_INT) { newEFLAGS |= EFlagsNTMask; // NT flag is set } // Step 10: Load the new task (dynamic) state from new TSS. // Any errors associated with loading and qualification of // segment descriptors in this step occur in the new task's // context. State loaded here includes LDTR, CR3, // EFLAGS, EIP, general purpose registers, and segment // descriptor parts of the segment registers. if ((tss_descriptor->type >= 9) && BX_CPU_THIS_PTR cr0.get_PG()) { // change CR3 only if it actually modified if (newCR3 != BX_CPU_THIS_PTR cr3) { SetCR3(newCR3); // Tell paging unit about new cr3 value BX_DEBUG (("task_switch changing CR3 to 0x" FMT_PHY_ADDRX, newCR3)); BX_INSTR_TLB_CNTRL(BX_CPU_ID, BX_INSTR_TASKSWITCH, newCR3); } } BX_CPU_THIS_PTR prev_rip = EIP = newEIP; EAX = newEAX; ECX = newECX; EDX = newEDX; EBX = newEBX; ESP = newESP; EBP = newEBP; ESI = newESI; EDI = newEDI; writeEFlags(newEFLAGS, EFlagsValidMask); // Fill in selectors for all segment registers. If errors // occur later, the selectors will at least be loaded. parse_selector(raw_cs_selector, &cs_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector = cs_selector; parse_selector(raw_ds_selector, &ds_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector = ds_selector; parse_selector(raw_es_selector, &es_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector = es_selector; parse_selector(raw_ss_selector, &ss_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector = ss_selector; parse_selector(raw_fs_selector, &fs_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector = fs_selector; parse_selector(raw_gs_selector, &gs_selector); BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector = gs_selector; parse_selector(raw_ldt_selector, &ldt_selector); BX_CPU_THIS_PTR ldtr.selector = ldt_selector; // Start out with invalid descriptor caches, fill in // with values only as they are validated. BX_CPU_THIS_PTR ldtr.cache.valid = 0; BX_CPU_THIS_PTR ldtr.cache.u.system.limit = 0; BX_CPU_THIS_PTR ldtr.cache.u.system.limit_scaled = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].cache.valid = 0; BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].cache.valid = 0; // LDTR if (ldt_selector.ti) { // LDT selector must be in GDT BX_INFO(("task_switch(exception after commit point): bad LDT selector TI=1")); exception(BX_TS_EXCEPTION, raw_ldt_selector & 0xfffc, 0); } if ((raw_ldt_selector & 0xfffc) != 0) { bx_bool good = fetch_raw_descriptor2(&ldt_selector, &dword1, &dword2); if (!good) { BX_ERROR(("task_switch(exception after commit point): bad LDT fetch")); exception(BX_TS_EXCEPTION, raw_ldt_selector & 0xfffc, 0); } parse_descriptor(dword1, dword2, &ldt_descriptor); // LDT selector of new task is valid, else #TS(new task's LDT) if (ldt_descriptor.valid==0 || ldt_descriptor.type!=BX_SYS_SEGMENT_LDT || ldt_descriptor.segment) { BX_ERROR(("task_switch(exception after commit point): bad LDT segment")); exception(BX_TS_EXCEPTION, raw_ldt_selector & 0xfffc, 0); } // LDT of new task is present in memory, else #TS(new tasks's LDT) if (! IS_PRESENT(ldt_descriptor)) { BX_ERROR(("task_switch(exception after commit point): LDT not present")); exception(BX_TS_EXCEPTION, raw_ldt_selector & 0xfffc, 0); } // All checks pass, fill in LDTR shadow cache BX_CPU_THIS_PTR ldtr.cache = ldt_descriptor; } else { // NULL LDT selector is OK, leave cache invalid } if (v8086_mode()) { // load seg regs as 8086 registers load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], raw_cs_selector); load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], raw_ss_selector); load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS], raw_ds_selector); load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES], raw_es_selector); load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS], raw_fs_selector); load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS], raw_gs_selector); } else { // SS if ((raw_ss_selector & 0xfffc) != 0) { bx_bool good = fetch_raw_descriptor2(&ss_selector, &dword1, &dword2); if (!good) { BX_ERROR(("task_switch(exception after commit point): bad SS fetch")); exception(BX_TS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } parse_descriptor(dword1, dword2, &ss_descriptor); // SS selector must be within its descriptor table limits else #TS(SS) // SS descriptor AR byte must must indicate writable data segment, // else #TS(SS) if (ss_descriptor.valid==0 || ss_descriptor.segment==0 || IS_CODE_SEGMENT(ss_descriptor.type) || !IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type)) { BX_ERROR(("task_switch(exception after commit point): SS not valid or writeable segment")); exception(BX_TS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } // // Stack segment is present in memory, else #SS(new stack segment) // if (! IS_PRESENT(ss_descriptor)) { BX_ERROR(("task_switch(exception after commit point): SS not present")); exception(BX_SS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } // Stack segment DPL matches CS.RPL, else #TS(new stack segment) if (ss_descriptor.dpl != cs_selector.rpl) { BX_ERROR(("task_switch(exception after commit point): SS.rpl != CS.RPL")); exception(BX_TS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } // Stack segment DPL matches selector RPL, else #TS(new stack segment) if (ss_descriptor.dpl != ss_selector.rpl) { BX_ERROR(("task_switch(exception after commit point): SS.dpl != SS.rpl")); exception(BX_TS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } // All checks pass, fill in shadow cache BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache = ss_descriptor; } else { // SS selector is valid, else #TS(new stack segment) BX_ERROR(("task_switch(exception after commit point): SS NULL")); exception(BX_TS_EXCEPTION, raw_ss_selector & 0xfffc, 0); } // if new selector is not null then perform following checks: // index must be within its descriptor table limits else #TS(selector) // AR byte must indicate data or readable code else #TS(selector) // if data or non-conforming code then: // DPL must be >= CPL else #TS(selector) // DPL must be >= RPL else #TS(selector) // AR byte must indicate PRESENT else #NP(selector) // load cache with new segment descriptor and set valid bit // CS if ((raw_cs_selector & 0xfffc) != 0) { bx_bool good = fetch_raw_descriptor2(&cs_selector, &dword1, &dword2); if (!good) { BX_ERROR(("task_switch(exception after commit point): bad CS fetch")); exception(BX_TS_EXCEPTION, raw_cs_selector & 0xfffc, 0); } parse_descriptor(dword1, dword2, &cs_descriptor); // CS descriptor AR byte must indicate code segment else #TS(CS) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type)) { BX_ERROR(("task_switch(exception after commit point): CS not valid executable seg")); exception(BX_TS_EXCEPTION, raw_cs_selector & 0xfffc, 0); } // if non-conforming then DPL must equal selector RPL else #TS(CS) if (IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && cs_descriptor.dpl != cs_selector.rpl) { BX_ERROR(("task_switch(exception after commit point): non-conforming: CS.dpl!=CS.RPL")); exception(BX_TS_EXCEPTION, raw_cs_selector & 0xfffc, 0); } // if conforming then DPL must be <= selector RPL else #TS(CS) if (IS_CODE_SEGMENT_CONFORMING(cs_descriptor.type) && cs_descriptor.dpl > cs_selector.rpl) { BX_ERROR(("task_switch(exception after commit point): conforming: CS.dpl>RPL")); exception(BX_TS_EXCEPTION, raw_cs_selector & 0xfffc, 0); } // Code segment is present in memory, else #NP(new code segment) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("task_switch(exception after commit point): CS.p==0")); exception(BX_NP_EXCEPTION, raw_cs_selector & 0xfffc, 0); } // All checks pass, fill in shadow cache BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache = cs_descriptor; } else { // If new cs selector is null #TS(CS) BX_ERROR(("task_switch(exception after commit point): CS NULL")); exception(BX_TS_EXCEPTION, raw_cs_selector & 0xfffc, 0); } #if BX_SUPPORT_ICACHE BX_CPU_THIS_PTR updateFetchModeMask(); #endif #if BX_CPU_LEVEL >= 4 && BX_SUPPORT_ALIGNMENT_CHECK handleAlignmentCheck(); // task switch, CPL was modified #endif task_switch_load_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS], &ds_selector, raw_ds_selector, cs_selector.rpl); task_switch_load_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES], &es_selector, raw_es_selector, cs_selector.rpl); task_switch_load_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS], &fs_selector, raw_fs_selector, cs_selector.rpl); task_switch_load_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS], &gs_selector, raw_gs_selector, cs_selector.rpl); } if ((tss_descriptor->type>=9) && (trap_word & 0x1)) { BX_CPU_THIS_PTR debug_trap |= 0x00008000; // BT flag in DR6 BX_CPU_THIS_PTR async_event = 1; // so processor knows to check BX_INFO(("task_switch: T bit set in new TSS")); } // // Step 14: Begin execution of new task. // BX_DEBUG(("TASKING: LEAVE")); }
BX_CPU_C::call_gate64(bx_selector_t *gate_selector) { bx_selector_t cs_selector; Bit32u dword1, dword2, dword3; bx_descriptor_t cs_descriptor; bx_descriptor_t gate_descriptor; // examine code segment selector in call gate descriptor BX_DEBUG(("call_gate64: CALL 64bit call gate")); fetch_raw_descriptor_64(gate_selector, &dword1, &dword2, &dword3, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &gate_descriptor); Bit16u dest_selector = gate_descriptor.u.gate.dest_selector; // selector must not be null else #GP(0) if ((dest_selector & 0xfffc) == 0) { BX_ERROR(("call_gate64: selector in gate null")); exception(BX_GP_EXCEPTION, 0, 0); } parse_selector(dest_selector, &cs_selector); // selector must be within its descriptor table limits, // else #GP(code segment selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // find the RIP in the gate_descriptor Bit64u new_RIP = gate_descriptor.u.gate.dest_offset; new_RIP |= ((Bit64u)dword3 << 32); // AR byte of selected descriptor must indicate code segment, // else #GP(code segment selector) // DPL of selected descriptor must be <= CPL, // else #GP(code segment selector) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type) || cs_descriptor.dpl > CPL) { BX_ERROR(("call_gate64: selected descriptor is not code")); exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0); } // In long mode, only 64-bit call gates are allowed, and they must point // to 64-bit code segments, else #GP(selector) if (! IS_LONG64_SEGMENT(cs_descriptor) || cs_descriptor.u.segment.d_b) { BX_ERROR(("call_gate64: not 64-bit code segment in call gate 64")); exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0); } // code segment must be present else #NP(selector) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("call_gate64: code segment not present !")); exception(BX_NP_EXCEPTION, dest_selector & 0xfffc, 0); } Bit64u old_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; Bit64u old_RIP = RIP; // CALL GATE TO MORE PRIVILEGE // if non-conforming code segment and DPL < CPL then if (IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && (cs_descriptor.dpl < CPL)) { Bit64u RSP_for_cpl_x; BX_DEBUG(("CALL GATE TO MORE PRIVILEGE LEVEL")); // get new RSP for new privilege level from TSS get_RSP_from_TSS(cs_descriptor.dpl, &RSP_for_cpl_x); Bit64u old_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; Bit64u old_RSP = RSP; if (! IsCanonical(RSP_for_cpl_x)) { // #SS(selector) when changing priviledge level BX_ERROR(("call_gate64: canonical address failure %08x%08x", GET32H(RSP_for_cpl_x), GET32L(RSP_for_cpl_x))); exception(BX_SS_EXCEPTION, old_SS & 0xfffc, 0); } // push old stack long pointer onto new stack write_new_stack_qword_64(RSP_for_cpl_x - 8, cs_descriptor.dpl, old_SS); write_new_stack_qword_64(RSP_for_cpl_x - 16, cs_descriptor.dpl, old_RSP); // push long pointer to return address onto new stack write_new_stack_qword_64(RSP_for_cpl_x - 24, cs_descriptor.dpl, old_CS); write_new_stack_qword_64(RSP_for_cpl_x - 32, cs_descriptor.dpl, old_RIP); RSP_for_cpl_x -= 32; // prepare new stack null SS selector bx_selector_t ss_selector; bx_descriptor_t ss_descriptor; // set up a null descriptor parse_selector(0, &ss_selector); parse_descriptor(0, 0, &ss_descriptor); // load CS:RIP (guaranteed to be in 64 bit mode) branch_far64(&cs_selector, &cs_descriptor, new_RIP, cs_descriptor.dpl); // set up null SS descriptor load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl); RSP = RSP_for_cpl_x; } else { BX_DEBUG(("CALL GATE TO SAME PRIVILEGE")); // push to 64-bit stack, switch to long64 guaranteed write_new_stack_qword_64(RSP - 8, CPL, old_CS); write_new_stack_qword_64(RSP - 16, CPL, old_RIP); RSP -= 16; // load CS:RIP (guaranteed to be in 64 bit mode) branch_far64(&cs_selector, &cs_descriptor, new_RIP, CPL); } }
BX_CPU_C::call_protected(bxInstruction_c *i, Bit16u cs_raw, bx_address disp) { bx_selector_t cs_selector; Bit32u dword1, dword2; bx_descriptor_t cs_descriptor; /* new cs selector must not be null, else #GP(0) */ if ((cs_raw & 0xfffc) == 0) { BX_ERROR(("call_protected: CS selector null")); exception(BX_GP_EXCEPTION, 0, 0); } parse_selector(cs_raw, &cs_selector); // check new CS selector index within its descriptor limits, // else #GP(new CS selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // examine AR byte of selected descriptor for various legal values if (cs_descriptor.valid==0) { BX_ERROR(("call_protected: invalid CS descriptor")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } if (cs_descriptor.segment) // normal segment { check_cs(&cs_descriptor, cs_raw, BX_SELECTOR_RPL(cs_raw), CPL); #if BX_SUPPORT_X86_64 if (i->os64L()) { // push return address onto stack (CS padded to 64bits) push_64((Bit64u) BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_64(RIP); } else #endif if (i->os32L()) { // push return address onto stack (CS padded to 32bits) push_32((Bit32u) BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_32(EIP); } else { // push return address onto stack push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_16(IP); } // load code segment descriptor into CS cache // load CS with new code segment selector // set RPL of CS to CPL branch_far64(&cs_selector, &cs_descriptor, disp, CPL); return; } else { // gate & special segment bx_descriptor_t gate_descriptor = cs_descriptor; bx_selector_t gate_selector = cs_selector; Bit32u new_EIP; Bit16u dest_selector; Bit16u raw_tss_selector; bx_selector_t tss_selector; bx_descriptor_t tss_descriptor; Bit32u temp_eIP; // descriptor DPL must be >= CPL else #GP(gate selector) if (gate_descriptor.dpl < CPL) { BX_ERROR(("call_protected: descriptor.dpl < CPL")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } // descriptor DPL must be >= gate selector RPL else #GP(gate selector) if (gate_descriptor.dpl < gate_selector.rpl) { BX_ERROR(("call_protected: descriptor.dpl < selector.rpl")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } #if BX_SUPPORT_X86_64 if (long_mode()) { // call gate type is higher priority than non-present bit check if (gate_descriptor.type != BX_386_CALL_GATE) { BX_ERROR(("call_protected: gate type %u unsupported in long mode", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } } else #endif { switch (gate_descriptor.type) { case BX_SYS_SEGMENT_AVAIL_286_TSS: case BX_SYS_SEGMENT_AVAIL_386_TSS: case BX_TASK_GATE: case BX_286_CALL_GATE: case BX_386_CALL_GATE: break; default: BX_ERROR(("call_protected(): gate.type(%u) unsupported", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } } // gate descriptor must be present else #NP(gate selector) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("call_protected: gate not present")); exception(BX_NP_EXCEPTION, cs_raw & 0xfffc, 0); } #if BX_SUPPORT_X86_64 if (long_mode()) { call_gate64(&gate_selector); return; } #endif switch (gate_descriptor.type) { case BX_SYS_SEGMENT_AVAIL_286_TSS: case BX_SYS_SEGMENT_AVAIL_386_TSS: if (gate_descriptor.type==BX_SYS_SEGMENT_AVAIL_286_TSS) BX_DEBUG(("call_protected: 16bit available TSS")); else BX_DEBUG(("call_protected: 32bit available TSS")); // SWITCH_TASKS _without_ nesting to TSS task_switch(&gate_selector, &gate_descriptor, BX_TASK_FROM_CALL_OR_INT, dword1, dword2); // EIP must be in code seg limit, else #GP(0) if (EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) { BX_ERROR(("call_protected: EIP not within CS limits")); exception(BX_GP_EXCEPTION, 0, 0); } return; case BX_TASK_GATE: // examine selector to TSS, given in Task Gate descriptor // must specify global in the local/global bit else #TS(TSS selector) raw_tss_selector = gate_descriptor.u.taskgate.tss_selector; parse_selector(raw_tss_selector, &tss_selector); if (tss_selector.ti) { BX_ERROR(("call_protected: tss_selector.ti=1")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0); } // index must be within GDT limits else #TS(TSS selector) fetch_raw_descriptor(&tss_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &tss_descriptor); // descriptor AR byte must specify available TSS // else #GP(TSS selector) if (tss_descriptor.valid==0 || tss_descriptor.segment) { BX_ERROR(("call_protected: TSS selector points to bad TSS")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0); } if (tss_descriptor.type!=BX_SYS_SEGMENT_AVAIL_286_TSS && tss_descriptor.type!=BX_SYS_SEGMENT_AVAIL_386_TSS) { BX_ERROR(("call_protected: TSS selector points to bad TSS")); exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0); } // task state segment must be present, else #NP(tss selector) if (! IS_PRESENT(tss_descriptor)) { BX_ERROR(("call_protected: task descriptor.p == 0")); exception(BX_NP_EXCEPTION, raw_tss_selector & 0xfffc, 0); } // SWITCH_TASKS without nesting to TSS task_switch(&tss_selector, &tss_descriptor, BX_TASK_FROM_CALL_OR_INT, dword1, dword2); // EIP must be within code segment limit, else #TS(0) if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.d_b) temp_eIP = EIP; else temp_eIP = IP; if (temp_eIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) { BX_ERROR(("call_protected: EIP > CS.limit")); exception(BX_GP_EXCEPTION, 0, 0); } return; case BX_286_CALL_GATE: case BX_386_CALL_GATE: // examine code segment selector in call gate descriptor BX_DEBUG(("call_protected: call gate")); dest_selector = gate_descriptor.u.gate.dest_selector; new_EIP = gate_descriptor.u.gate.dest_offset; // selector must not be null else #GP(0) if ((dest_selector & 0xfffc) == 0) { BX_ERROR(("call_protected: selector in gate null")); exception(BX_GP_EXCEPTION, 0, 0); } parse_selector(dest_selector, &cs_selector); // selector must be within its descriptor table limits, // else #GP(code segment selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // AR byte of selected descriptor must indicate code segment, // else #GP(code segment selector) // DPL of selected descriptor must be <= CPL, // else #GP(code segment selector) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type) || cs_descriptor.dpl > CPL) { BX_ERROR(("call_protected: selected descriptor is not code")); exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0); } // code segment must be present else #NP(selector) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("call_protected: code segment not present !")); exception(BX_NP_EXCEPTION, dest_selector & 0xfffc, 0); } // CALL GATE TO MORE PRIVILEGE // if non-conforming code segment and DPL < CPL then if (IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && (cs_descriptor.dpl < CPL)) { Bit16u SS_for_cpl_x; Bit32u ESP_for_cpl_x; bx_selector_t ss_selector; bx_descriptor_t ss_descriptor; Bit16u return_SS, return_CS; Bit32u return_ESP, return_EIP; Bit16u parameter_word[32]; Bit32u parameter_dword[32]; BX_DEBUG(("CALL GATE TO MORE PRIVILEGE LEVEL")); // get new SS selector for new privilege level from TSS get_SS_ESP_from_TSS(cs_descriptor.dpl, &SS_for_cpl_x, &ESP_for_cpl_x); // check selector & descriptor for new SS: // selector must not be null, else #TS(0) if ((SS_for_cpl_x & 0xfffc) == 0) { BX_ERROR(("call_protected: new SS null")); exception(BX_TS_EXCEPTION, 0, 0); } // selector index must be within its descriptor table limits, // else #TS(SS selector) parse_selector(SS_for_cpl_x, &ss_selector); fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_TS_EXCEPTION); parse_descriptor(dword1, dword2, &ss_descriptor); // selector's RPL must equal DPL of code segment, // else #TS(SS selector) if (ss_selector.rpl != cs_descriptor.dpl) { BX_ERROR(("call_protected: SS selector.rpl != CS descr.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0); } // stack segment DPL must equal DPL of code segment, // else #TS(SS selector) if (ss_descriptor.dpl != cs_descriptor.dpl) { BX_ERROR(("call_protected: SS descr.rpl != CS descr.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0); } // descriptor must indicate writable data segment, // else #TS(SS selector) if (ss_descriptor.valid==0 || ss_descriptor.segment==0 || IS_CODE_SEGMENT(ss_descriptor.type) || !IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type)) { BX_ERROR(("call_protected: ss descriptor is not writable data seg")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0); } // segment must be present, else #SS(SS selector) if (! IS_PRESENT(ss_descriptor)) { BX_ERROR(("call_protected: ss descriptor not present")); exception(BX_SS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0); } // get word count from call gate, mask to 5 bits unsigned param_count = gate_descriptor.u.gate.param_count & 0x1f; // save return SS:eSP to be pushed on new stack return_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) return_ESP = ESP; else return_ESP = SP; // save return CS:eIP to be pushed on new stack return_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; if (cs_descriptor.u.segment.d_b) return_EIP = EIP; else return_EIP = IP; if (gate_descriptor.type==BX_286_CALL_GATE) { for (unsigned i=0; i<param_count; i++) { parameter_word[i] = read_virtual_word(BX_SEG_REG_SS, return_ESP + i*2); } } else { for (unsigned i=0; i<param_count; i++) { parameter_dword[i] = read_virtual_dword(BX_SEG_REG_SS, return_ESP + i*4); } } // Prepare new stack segment bx_segment_reg_t new_stack; new_stack.selector = ss_selector; new_stack.cache = ss_descriptor; new_stack.selector.rpl = cs_descriptor.dpl; // add cpl to the selector value new_stack.selector.value = (0xfffc & new_stack.selector.value) | new_stack.selector.rpl; /* load new SS:SP value from TSS */ if (ss_descriptor.u.segment.d_b) { Bit32u temp_ESP = ESP_for_cpl_x; // push pointer of old stack onto new stack if (gate_descriptor.type==BX_386_CALL_GATE) { write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, return_SS); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, return_ESP); temp_ESP -= 8; for (unsigned i=param_count; i>0; i--) { temp_ESP -= 4; write_new_stack_dword_32(&new_stack, temp_ESP, cs_descriptor.dpl, parameter_dword[i-1]); } // push return address onto new stack write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, return_CS); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, return_EIP); temp_ESP -= 8; } else { write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, return_SS); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, (Bit16u) return_ESP); temp_ESP -= 4; for (unsigned i=param_count; i>0; i--) { temp_ESP -= 2; write_new_stack_word_32(&new_stack, temp_ESP, cs_descriptor.dpl, parameter_word[i-1]); } // push return address onto new stack write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, return_CS); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, (Bit16u) return_EIP); temp_ESP -= 4; } ESP = temp_ESP; } else { Bit16u temp_SP = (Bit16u) ESP_for_cpl_x; // push pointer of old stack onto new stack if (gate_descriptor.type==BX_386_CALL_GATE) { write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, return_SS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, return_ESP); temp_SP -= 8; for (unsigned i=param_count; i>0; i--) { temp_SP -= 4; write_new_stack_dword_32(&new_stack, temp_SP, cs_descriptor.dpl, parameter_dword[i-1]); } // push return address onto new stack write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, return_CS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, return_EIP); temp_SP -= 8; } else { write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, return_SS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, (Bit16u) return_ESP); temp_SP -= 4; for (unsigned i=param_count; i>0; i--) { temp_SP -= 2; write_new_stack_word_32(&new_stack, temp_SP, cs_descriptor.dpl, parameter_word[i-1]); } // push return address onto new stack write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, return_CS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, (Bit16u) return_EIP); temp_SP -= 4; } SP = temp_SP; } // new eIP must be in code segment limit else #GP(0) if (new_EIP > cs_descriptor.u.segment.limit_scaled) { BX_ERROR(("call_protected: EIP not within CS limits")); exception(BX_GP_EXCEPTION, 0, 0); } /* load SS descriptor */ load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl); /* load new CS:IP value from gate */ /* load CS descriptor */ /* set CPL to stack segment DPL */ /* set RPL of CS to CPL */ load_cs(&cs_selector, &cs_descriptor, cs_descriptor.dpl); EIP = new_EIP; } else // CALL GATE TO SAME PRIVILEGE { BX_DEBUG(("CALL GATE TO SAME PRIVILEGE")); if (gate_descriptor.type == BX_386_CALL_GATE) { // call gate 32bit, push return address onto stack push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_32(EIP); } else { // call gate 16bit, push return address onto stack push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_16(IP); } // load CS:EIP from gate // load code segment descriptor into CS register // set RPL of CS to CPL branch_far32(&cs_selector, &cs_descriptor, new_EIP, CPL); } return; default: // can't get here BX_PANIC(("call_protected: gate type %u unsupported", (unsigned) cs_descriptor.type)); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0); } } }
BX_CPU_C::call_protected(bxInstruction_c *i, Bit16u cs_raw, bx_address disp) { bx_selector_t cs_selector; Bit32u dword1, dword2; bx_descriptor_t cs_descriptor; /* new cs selector must not be null, else #GP(0) */ if ((cs_raw & 0xfffc) == 0) { BX_ERROR(("call_protected: CS selector null")); exception(BX_GP_EXCEPTION, 0); } parse_selector(cs_raw, &cs_selector); // check new CS selector index within its descriptor limits, // else #GP(new CS selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // examine AR byte of selected descriptor for various legal values if (cs_descriptor.valid==0) { BX_ERROR(("call_protected: invalid CS descriptor")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } if (cs_descriptor.segment) // normal segment { check_cs(&cs_descriptor, cs_raw, BX_SELECTOR_RPL(cs_raw), CPL); #if BX_SUPPORT_X86_64 if (long_mode() && cs_descriptor.u.segment.l) { Bit64u temp_rsp = RSP; // moving to long mode, push return address onto 64-bit stack if (i->os64L()) { write_new_stack_qword_64(temp_rsp - 8, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_qword_64(temp_rsp - 16, cs_descriptor.dpl, RIP); temp_rsp -= 16; } else if (i->os32L()) { write_new_stack_dword_64(temp_rsp - 4, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_dword_64(temp_rsp - 8, cs_descriptor.dpl, EIP); temp_rsp -= 8; } else { write_new_stack_word_64(temp_rsp - 2, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_word_64(temp_rsp - 4, cs_descriptor.dpl, IP); temp_rsp -= 4; } // load code segment descriptor into CS cache // load CS with new code segment selector // set RPL of CS to CPL branch_far64(&cs_selector, &cs_descriptor, disp, CPL); RSP = temp_rsp; } else #endif { Bit32u temp_RSP; // moving to legacy mode, push return address onto 32-bit stack if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) temp_RSP = ESP; else temp_RSP = SP; #if BX_SUPPORT_X86_64 if (i->os64L()) { write_new_stack_qword_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 8, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_qword_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 16, cs_descriptor.dpl, RIP); temp_RSP -= 16; } else #endif if (i->os32L()) { write_new_stack_dword_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 4, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_dword_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 8, cs_descriptor.dpl, EIP); temp_RSP -= 8; } else { write_new_stack_word_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 2, cs_descriptor.dpl, BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); write_new_stack_word_32(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], temp_RSP - 4, cs_descriptor.dpl, IP); temp_RSP -= 4; } // load code segment descriptor into CS cache // load CS with new code segment selector // set RPL of CS to CPL branch_far64(&cs_selector, &cs_descriptor, disp, CPL); if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) ESP = (Bit32u) temp_RSP; else SP = (Bit16u) temp_RSP; } return; } else { // gate & special segment bx_descriptor_t gate_descriptor = cs_descriptor; bx_selector_t gate_selector = cs_selector; // descriptor DPL must be >= CPL else #GP(gate selector) if (gate_descriptor.dpl < CPL) { BX_ERROR(("call_protected: descriptor.dpl < CPL")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } // descriptor DPL must be >= gate selector RPL else #GP(gate selector) if (gate_descriptor.dpl < gate_selector.rpl) { BX_ERROR(("call_protected: descriptor.dpl < selector.rpl")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } #if BX_SUPPORT_X86_64 if (long_mode()) { // call gate type is higher priority than non-present bit check if (gate_descriptor.type != BX_386_CALL_GATE) { BX_ERROR(("call_protected: gate type %u unsupported in long mode", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } // gate descriptor must be present else #NP(gate selector) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("call_protected: call gate not present")); exception(BX_NP_EXCEPTION, cs_raw & 0xfffc); } call_gate64(&gate_selector); return; } #endif switch (gate_descriptor.type) { case BX_SYS_SEGMENT_AVAIL_286_TSS: case BX_SYS_SEGMENT_AVAIL_386_TSS: if (gate_descriptor.type==BX_SYS_SEGMENT_AVAIL_286_TSS) BX_DEBUG(("call_protected: 16bit available TSS")); else BX_DEBUG(("call_protected: 32bit available TSS")); if (gate_descriptor.valid==0 || gate_selector.ti) { BX_ERROR(("call_protected: call bad TSS selector !")); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } // TSS must be present, else #NP(TSS selector) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("call_protected: call not present TSS !")); exception(BX_NP_EXCEPTION, cs_raw & 0xfffc); } // SWITCH_TASKS _without_ nesting to TSS task_switch(i, &gate_selector, &gate_descriptor, BX_TASK_FROM_CALL, dword1, dword2); // EIP must be in code seg limit, else #GP(0) if (EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) { BX_ERROR(("call_protected: EIP not within CS limits")); exception(BX_GP_EXCEPTION, 0); } return; case BX_TASK_GATE: task_gate(i, &gate_selector, &gate_descriptor, BX_TASK_FROM_CALL); return; case BX_286_CALL_GATE: case BX_386_CALL_GATE: // gate descriptor must be present else #NP(gate selector) if (! IS_PRESENT(gate_descriptor)) { BX_ERROR(("call_protected: gate not present")); exception(BX_NP_EXCEPTION, cs_raw & 0xfffc); } call_gate(&gate_descriptor); return; default: // can't get here BX_ERROR(("call_protected(): gate.type(%u) unsupported", (unsigned) gate_descriptor.type)); exception(BX_GP_EXCEPTION, cs_raw & 0xfffc); } } }
void BX_CPP_AttrRegparmN(1) BX_CPU_C::call_gate(bx_descriptor_t *gate_descriptor) { bx_selector_t cs_selector; Bit32u dword1, dword2; bx_descriptor_t cs_descriptor; // examine code segment selector in call gate descriptor BX_DEBUG(("call_protected: call gate")); Bit16u dest_selector = gate_descriptor->u.gate.dest_selector; Bit32u new_EIP = gate_descriptor->u.gate.dest_offset; // selector must not be null else #GP(0) if ((dest_selector & 0xfffc) == 0) { BX_ERROR(("call_protected: selector in gate null")); exception(BX_GP_EXCEPTION, 0); } parse_selector(dest_selector, &cs_selector); // selector must be within its descriptor table limits, // else #GP(code segment selector) fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION); parse_descriptor(dword1, dword2, &cs_descriptor); // AR byte of selected descriptor must indicate code segment, // else #GP(code segment selector) // DPL of selected descriptor must be <= CPL, // else #GP(code segment selector) if (cs_descriptor.valid==0 || cs_descriptor.segment==0 || IS_DATA_SEGMENT(cs_descriptor.type) || cs_descriptor.dpl > CPL) { BX_ERROR(("call_protected: selected descriptor is not code")); exception(BX_GP_EXCEPTION, dest_selector & 0xfffc); } // code segment must be present else #NP(selector) if (! IS_PRESENT(cs_descriptor)) { BX_ERROR(("call_protected: code segment not present !")); exception(BX_NP_EXCEPTION, dest_selector & 0xfffc); } // CALL GATE TO MORE PRIVILEGE // if non-conforming code segment and DPL < CPL then if (IS_CODE_SEGMENT_NON_CONFORMING(cs_descriptor.type) && (cs_descriptor.dpl < CPL)) { Bit16u SS_for_cpl_x; Bit32u ESP_for_cpl_x; bx_selector_t ss_selector; bx_descriptor_t ss_descriptor; Bit16u return_SS, return_CS; Bit32u return_ESP, return_EIP; BX_DEBUG(("CALL GATE TO MORE PRIVILEGE LEVEL")); // get new SS selector for new privilege level from TSS get_SS_ESP_from_TSS(cs_descriptor.dpl, &SS_for_cpl_x, &ESP_for_cpl_x); // check selector & descriptor for new SS: // selector must not be null, else #TS(0) if ((SS_for_cpl_x & 0xfffc) == 0) { BX_ERROR(("call_protected: new SS null")); exception(BX_TS_EXCEPTION, 0); } // selector index must be within its descriptor table limits, // else #TS(SS selector) parse_selector(SS_for_cpl_x, &ss_selector); fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_TS_EXCEPTION); parse_descriptor(dword1, dword2, &ss_descriptor); // selector's RPL must equal DPL of code segment, // else #TS(SS selector) if (ss_selector.rpl != cs_descriptor.dpl) { BX_ERROR(("call_protected: SS selector.rpl != CS descr.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // stack segment DPL must equal DPL of code segment, // else #TS(SS selector) if (ss_descriptor.dpl != cs_descriptor.dpl) { BX_ERROR(("call_protected: SS descr.rpl != CS descr.dpl")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // descriptor must indicate writable data segment, // else #TS(SS selector) if (ss_descriptor.valid==0 || ss_descriptor.segment==0 || IS_CODE_SEGMENT(ss_descriptor.type) || !IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type)) { BX_ERROR(("call_protected: ss descriptor is not writable data seg")); exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // segment must be present, else #SS(SS selector) if (! IS_PRESENT(ss_descriptor)) { BX_ERROR(("call_protected: ss descriptor not present")); exception(BX_SS_EXCEPTION, SS_for_cpl_x & 0xfffc); } // get word count from call gate, mask to 5 bits unsigned param_count = gate_descriptor->u.gate.param_count & 0x1f; // save return SS:eSP to be pushed on new stack return_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value; if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) return_ESP = ESP; else return_ESP = SP; // save return CS:eIP to be pushed on new stack return_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value; if (cs_descriptor.u.segment.d_b) return_EIP = EIP; else return_EIP = IP; // Prepare new stack segment bx_segment_reg_t new_stack; new_stack.selector = ss_selector; new_stack.cache = ss_descriptor; new_stack.selector.rpl = cs_descriptor.dpl; // add cpl to the selector value new_stack.selector.value = (0xfffc & new_stack.selector.value) | new_stack.selector.rpl; /* load new SS:SP value from TSS */ if (ss_descriptor.u.segment.d_b) { Bit32u temp_ESP = ESP_for_cpl_x; // push pointer of old stack onto new stack if (gate_descriptor->type==BX_386_CALL_GATE) { write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, return_SS); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, return_ESP); temp_ESP -= 8; for (unsigned n=param_count; n>0; n--) { temp_ESP -= 4; Bit32u param = read_virtual_dword_32(BX_SEG_REG_SS, return_ESP + (n-1)*4); write_new_stack_dword_32(&new_stack, temp_ESP, cs_descriptor.dpl, param); } // push return address onto new stack write_new_stack_dword_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, return_CS); write_new_stack_dword_32(&new_stack, temp_ESP-8, cs_descriptor.dpl, return_EIP); temp_ESP -= 8; } else { write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, return_SS); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, (Bit16u) return_ESP); temp_ESP -= 4; for (unsigned n=param_count; n>0; n--) { temp_ESP -= 2; Bit16u param = read_virtual_word_32(BX_SEG_REG_SS, return_ESP + (n-1)*2); write_new_stack_word_32(&new_stack, temp_ESP, cs_descriptor.dpl, param); } // push return address onto new stack write_new_stack_word_32(&new_stack, temp_ESP-2, cs_descriptor.dpl, return_CS); write_new_stack_word_32(&new_stack, temp_ESP-4, cs_descriptor.dpl, (Bit16u) return_EIP); temp_ESP -= 4; } ESP = temp_ESP; } else { Bit16u temp_SP = (Bit16u) ESP_for_cpl_x; // push pointer of old stack onto new stack if (gate_descriptor->type==BX_386_CALL_GATE) { write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, return_SS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, return_ESP); temp_SP -= 8; for (unsigned n=param_count; n>0; n--) { temp_SP -= 4; Bit32u param = read_virtual_dword_32(BX_SEG_REG_SS, return_ESP + (n-1)*4); write_new_stack_dword_32(&new_stack, temp_SP, cs_descriptor.dpl, param); } // push return address onto new stack write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, return_CS); write_new_stack_dword_32(&new_stack, (Bit16u)(temp_SP-8), cs_descriptor.dpl, return_EIP); temp_SP -= 8; } else { write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, return_SS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, (Bit16u) return_ESP); temp_SP -= 4; for (unsigned n=param_count; n>0; n--) { temp_SP -= 2; Bit16u param = read_virtual_word_32(BX_SEG_REG_SS, return_ESP + (n-1)*2); write_new_stack_word_32(&new_stack, temp_SP, cs_descriptor.dpl, param); } // push return address onto new stack write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-2), cs_descriptor.dpl, return_CS); write_new_stack_word_32(&new_stack, (Bit16u)(temp_SP-4), cs_descriptor.dpl, (Bit16u) return_EIP); temp_SP -= 4; } SP = temp_SP; } // new eIP must be in code segment limit else #GP(0) if (new_EIP > cs_descriptor.u.segment.limit_scaled) { BX_ERROR(("call_protected: EIP not within CS limits")); exception(BX_GP_EXCEPTION, 0); } /* load SS descriptor */ load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl); /* load new CS:IP value from gate */ /* load CS descriptor */ /* set CPL to stack segment DPL */ /* set RPL of CS to CPL */ load_cs(&cs_selector, &cs_descriptor, cs_descriptor.dpl); EIP = new_EIP; } else // CALL GATE TO SAME PRIVILEGE { BX_DEBUG(("CALL GATE TO SAME PRIVILEGE")); if (gate_descriptor->type == BX_386_CALL_GATE) { // call gate 32bit, push return address onto stack push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_32(EIP); } else { // call gate 16bit, push return address onto stack push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value); push_16(IP); } // load CS:EIP from gate // load code segment descriptor into CS register // set RPL of CS to CPL branch_far32(&cs_selector, &cs_descriptor, new_EIP, CPL); } }