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(); }
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); } }