From cb60cdebdc36dd2358fe1ce06eec197e213af491 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Tue, 24 Mar 2026 17:35:54 +0100 Subject: kapi/cpu: introduce CPU API --- arch/x86_64/src/cpu/interrupts.cpp | 125 +++++++++++++++++++++++++++---------- 1 file changed, 91 insertions(+), 34 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 048c461..6f66bbd 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -1,6 +1,7 @@ #include "arch/cpu/interrupts.hpp" #include "kapi/cpu.hpp" +#include "kapi/memory.hpp" #include "arch/cpu/legacy_pic.hpp" #include "arch/cpu/segment_selector.hpp" @@ -14,38 +15,92 @@ namespace arch::cpu namespace { - constexpr auto isr_number_page_fault = 0x0e; - constexpr auto isr_number_legacy_start = 0x20; - constexpr auto isr_number_legacy_end = 0x29; - constexpr auto isr_number_cascade_start = 0x2c; - constexpr auto isr_number_cascade_end = 0x2f; - - auto handle_page_fault(interrupt_frame * frame) -> void + enum struct exception { - auto fault_address = std::uintptr_t{}; - asm volatile("mov %%cr2, %0" : "=r"(fault_address)); - - auto const present = (frame->interrupt.error_code & 0x1) != 0; - auto const write = (frame->interrupt.error_code & 0x2) != 0; - auto const user = (frame->interrupt.error_code & 0x4) != 0; + divide_error, + debug_exception, + non_maskable_interrupt, + breakpoint, + overflow, + bound_range_exceeded, + invalid_opcode, + device_not_available, + double_fault, + coprocessor_segment_overrun, + invalid_tss, + stack_segment_fault, + general_protection_fault, + page_fault, + x87_fpu_floating_point_error, + alignment_check, + machine_check, + simd_floating_point_error, + virtualization_exception, + control_protection_exception, + vmm_communication_exception, + security_exception, + }; + + constexpr auto pic_master_irq_start = 0x20; + constexpr auto pic_master_irq_end = pic_master_irq_start + 8; + constexpr auto pic_slave_irq_start = pic_master_irq_end; + constexpr auto pic_slave_irq_end = pic_slave_irq_start + 8; + + constexpr auto to_exception_type(exception e) + { + switch (e) + { + case exception::divide_error: + case exception::x87_fpu_floating_point_error: + case exception::simd_floating_point_error: + return kapi::cpu::exception::type::arithmetic_error; + case exception::breakpoint: + return kapi::cpu::exception::type::breakpoint; + case exception::invalid_opcode: + return kapi::cpu::exception::type::illegal_instruction; + case exception::stack_segment_fault: + return kapi::cpu::exception::type::memory_access_fault; + case exception::general_protection_fault: + return kapi::cpu::exception::type::privilege_violation; + case exception::alignment_check: + return kapi::cpu::exception::type::alignment_fault; + default: + return kapi::cpu::exception::type::unknown; + } + } - kstd::println(kstd::print_sink::stderr, "[x86_64:MMU] PAGE FAULT!"); - kstd::println(kstd::print_sink::stderr, "\tFault address: {:#018x}", fault_address); - kstd::println(kstd::print_sink::stderr, "\tPresent: {}", present); - kstd::println(kstd::print_sink::stderr, "\tWrite: {}", write); - kstd::println(kstd::print_sink::stderr, "\tUser: {}", user); - kstd::println(kstd::print_sink::stderr, "\tRIP: {:#018x}", frame->cpu_saved.rip); - kstd::println(kstd::print_sink::stderr, "\tHalting the system now!"); + auto dispatch_exception(interrupt_frame * frame) -> bool + { + auto type = to_exception_type(static_cast(frame->interrupt.number)); + auto fault_address = kapi::memory::linear_address{}; + auto instruction_pointer = frame->cpu_saved.rip; - kapi::cpu::halt(); + switch (type) + { + case kapi::cpu::exception::type::page_fault: + { + asm volatile("mov %%cr2, %0" : "=r"(fault_address)); + auto present = (frame->interrupt.error_code & 0x1) != 0; + auto write = (frame->interrupt.error_code & 0x2) != 0; + auto user = (frame->interrupt.error_code & 0x4) != 0; + + return kapi::cpu::get_exception_handler().handle( + {type, instruction_pointer, fault_address, present, write, user}); + } + default: + return kapi::cpu::get_exception_handler().handle({type, instruction_pointer}); + } } auto handle_legacy_interrupt(interrupt_frame * frame) -> void { kstd::println("[x86_64:SYS] Ignoring 8259 legacy interrupt {:#04x}", frame->interrupt.number); + if (frame->interrupt.number >= pic_slave_irq_start) + { + pic_slave_control_port::write(pic_end_of_interrupt); + } pic_master_control_port::write(pic_end_of_interrupt); - pic_slave_control_port::write(pic_end_of_interrupt); } } // namespace @@ -55,23 +110,25 @@ namespace arch::cpu auto interrupt_dispatch(interrupt_frame * frame) -> void { - if ((frame->interrupt.number >= isr_number_legacy_start && frame->interrupt.number <= isr_number_legacy_end) || - (frame->interrupt.number >= isr_number_cascade_start && frame->interrupt.number <= isr_number_cascade_end)) + auto [number, code] = frame->interrupt; + + if (number < pic_master_irq_start && !dispatch_exception(frame)) { - handle_legacy_interrupt(frame); - return; + kstd::println(kstd::print_sink::stderr, + "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); + kapi::cpu::halt(); } - switch (frame->interrupt.number) + if ((number >= pic_master_irq_start && number < pic_master_irq_end) || + (number >= pic_slave_irq_start && number < pic_slave_irq_end)) { - case isr_number_page_fault: - handle_page_fault(frame); - break; - default: - kstd::println(kstd::print_sink::stderr, "[x86_64:SYS] Unhandled interrupt {:#04x} received with code {:#04x}", - frame->interrupt.number, frame->interrupt.error_code); - kapi::cpu::halt(); + handle_legacy_interrupt(frame); + return; } + + kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x} received with code {:#04x}", + frame->interrupt.number, frame->interrupt.error_code); + kapi::cpu::halt(); } } -- cgit v1.2.3 From 42895684b631380c8aca94f82209297ac0c0e5f2 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Tue, 24 Mar 2026 17:44:21 +0100 Subject: kapi: extract interrupt enablement --- arch/x86_64/src/cpu/interrupts.cpp | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 6f66bbd..dc236e6 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -168,14 +168,4 @@ namespace arch::cpu return idtr; } - auto enable_interrupts() -> void - { - asm volatile("sti"); - } - - auto disable_interrupts() -> void - { - asm volatile("cli"); - } - } // namespace arch::cpu \ No newline at end of file -- cgit v1.2.3 From 363a6d701d4998137fcc123059f9749098ac7d75 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Wed, 25 Mar 2026 08:12:49 +0100 Subject: x86_64/cpu: fix exception enum --- arch/x86_64/src/cpu/interrupts.cpp | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index dc236e6..e578aa2 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -28,15 +28,17 @@ namespace arch::cpu double_fault, coprocessor_segment_overrun, invalid_tss, + segment_not_present, stack_segment_fault, general_protection_fault, page_fault, - x87_fpu_floating_point_error, + x87_fpu_floating_point_error = 16, alignment_check, machine_check, simd_floating_point_error, virtualization_exception, control_protection_exception, + hypervisor_injection_exception = 28, vmm_communication_exception, security_exception, }; @@ -62,6 +64,8 @@ namespace arch::cpu return kapi::cpu::exception::type::memory_access_fault; case exception::general_protection_fault: return kapi::cpu::exception::type::privilege_violation; + case exception::page_fault: + return kapi::cpu::exception::type::page_fault; case exception::alignment_check: return kapi::cpu::exception::type::alignment_fault; default: -- cgit v1.2.3 From a82416648d148152338dc612c25bf8dff428e773 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Wed, 25 Mar 2026 16:39:13 +0100 Subject: kapi: introduce cpu::interrupt_handler --- arch/x86_64/src/cpu/interrupts.cpp | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index e578aa2..1f65336 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -46,7 +46,6 @@ namespace arch::cpu constexpr auto pic_master_irq_start = 0x20; constexpr auto pic_master_irq_end = pic_master_irq_start + 8; constexpr auto pic_slave_irq_start = pic_master_irq_end; - constexpr auto pic_slave_irq_end = pic_slave_irq_start + 8; constexpr auto to_exception_type(exception e) { @@ -96,10 +95,8 @@ namespace arch::cpu } } - auto handle_legacy_interrupt(interrupt_frame * frame) -> void + auto acknowledge_pic_interrupt(interrupt_frame * frame) -> void { - kstd::println("[x86_64:SYS] Ignoring 8259 legacy interrupt {:#04x}", frame->interrupt.number); - if (frame->interrupt.number >= pic_slave_irq_start) { pic_slave_control_port::write(pic_end_of_interrupt); @@ -120,19 +117,13 @@ namespace arch::cpu { kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); - kapi::cpu::halt(); } - - if ((number >= pic_master_irq_start && number < pic_master_irq_end) || - (number >= pic_slave_irq_start && number < pic_slave_irq_end)) + else if (number >= pic_master_irq_start && kapi::cpu::dispatch_interrupt(number) == kapi::cpu::status::unhandled) { - handle_legacy_interrupt(frame); - return; + kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x}", number); } - kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x} received with code {:#04x}", - frame->interrupt.number, frame->interrupt.error_code); - kapi::cpu::halt(); + acknowledge_pic_interrupt(frame); } } -- cgit v1.2.3 From 953768ed7af8692818f742566864bfd264a824a2 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Wed, 25 Mar 2026 18:37:55 +0100 Subject: x86_64/cpu: fix interrupt gate types --- arch/x86_64/src/cpu/interrupts.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 1f65336..1f12898 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -135,7 +135,7 @@ namespace arch::cpu .offset_low = static_cast(isr_stub_table[i] & 0xffff), // NOLINT(readability-magic-numbers) .m_code_segment = segment_selector{0, false, 1}, .interrupt_stack_table_selector = 0, - .gate_type = gate_type::interrupt_gate, + .gate_type = (i < 32 && i != 2) ? gate_type::trap_gate : gate_type::interrupt_gate, .descriptor_privilege_level = 0, .present = true, .offset_middle = -- cgit v1.2.3 From 6a1addc7663bfae3306abb8800d3e387b3f66e82 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Wed, 25 Mar 2026 18:46:20 +0100 Subject: x86_64/cpu: improve exception logging --- arch/x86_64/src/cpu/interrupts.cpp | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 1f12898..4e52d71 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -43,6 +43,8 @@ namespace arch::cpu security_exception, }; + constexpr auto number_of_exception_vectors = 32u; + constexpr auto pic_master_irq_start = 0x20; constexpr auto pic_master_irq_end = pic_master_irq_start + 8; constexpr auto pic_slave_irq_start = pic_master_irq_end; @@ -72,6 +74,25 @@ namespace arch::cpu } } + constexpr auto has_error_code(exception e) + { + switch (e) + { + case exception::double_fault: + case exception::invalid_tss: + case exception::segment_not_present: + case exception::stack_segment_fault: + case exception::general_protection_fault: + case exception::page_fault: + case exception::alignment_check: + case exception::control_protection_exception: + case exception::security_exception: + return true; + default: + return false; + } + } + auto dispatch_exception(interrupt_frame * frame) -> bool { auto type = to_exception_type(static_cast(frame->interrupt.number)); @@ -113,12 +134,20 @@ namespace arch::cpu { auto [number, code] = frame->interrupt; - if (number < pic_master_irq_start && !dispatch_exception(frame)) + if (number < number_of_exception_vectors && !dispatch_exception(frame)) { - kstd::println(kstd::print_sink::stderr, - "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); + if (has_error_code(static_cast(number))) + { + kstd::println(kstd::print_sink::stderr, + "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); + } + else + { + kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled exception number {:#04x} received", number); + } } - else if (number >= pic_master_irq_start && kapi::cpu::dispatch_interrupt(number) == kapi::cpu::status::unhandled) + else if (number >= number_of_exception_vectors && + kapi::cpu::dispatch_interrupt(number) == kapi::cpu::status::unhandled) { kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x}", number); } -- cgit v1.2.3 From 8d06763f47e7b7c93af2a55f6bd2dbc4aa9abfa2 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Thu, 26 Mar 2026 16:10:50 +0100 Subject: kapi/cpu: simplify exception handling --- arch/x86_64/src/cpu/interrupts.cpp | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 4e52d71..9ee3ce8 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -108,11 +108,10 @@ namespace arch::cpu auto write = (frame->interrupt.error_code & 0x2) != 0; auto user = (frame->interrupt.error_code & 0x4) != 0; - return kapi::cpu::get_exception_handler().handle( - {type, instruction_pointer, fault_address, present, write, user}); + return kapi::cpu::dispatch({type, instruction_pointer, fault_address, present, write, user}); } default: - return kapi::cpu::get_exception_handler().handle({type, instruction_pointer}); + return kapi::cpu::dispatch({type, instruction_pointer}); } } -- cgit v1.2.3 From 00a77644192642e06462c11479a5c0e9bd859e9a Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Thu, 26 Mar 2026 16:35:32 +0100 Subject: kapi: extract interrupts API --- arch/x86_64/src/cpu/interrupts.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 9ee3ce8..2f23f07 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -1,6 +1,7 @@ #include "arch/cpu/interrupts.hpp" #include "kapi/cpu.hpp" +#include "kapi/interrupts.hpp" #include "kapi/memory.hpp" #include "arch/cpu/legacy_pic.hpp" @@ -146,7 +147,7 @@ namespace arch::cpu } } else if (number >= number_of_exception_vectors && - kapi::cpu::dispatch_interrupt(number) == kapi::cpu::status::unhandled) + kapi::interrupts::dispatch(number) == kapi::interrupts::status::unhandled) { kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x}", number); } -- cgit v1.2.3 From aa68f53d2502e0ea81c8e9c95e37d9847cb6cb16 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Thu, 26 Mar 2026 17:15:26 +0100 Subject: arch/cpu: fix interrupt dispatch --- arch/x86_64/src/cpu/interrupts.cpp | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) (limited to 'arch/x86_64/src/cpu') diff --git a/arch/x86_64/src/cpu/interrupts.cpp b/arch/x86_64/src/cpu/interrupts.cpp index 2f23f07..907f289 100644 --- a/arch/x86_64/src/cpu/interrupts.cpp +++ b/arch/x86_64/src/cpu/interrupts.cpp @@ -134,25 +134,33 @@ namespace arch::cpu { auto [number, code] = frame->interrupt; - if (number < number_of_exception_vectors && !dispatch_exception(frame)) + if (number < number_of_exception_vectors) { - if (has_error_code(static_cast(number))) + if (!dispatch_exception(frame)) { - kstd::println(kstd::print_sink::stderr, - "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); - } - else - { - kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled exception number {:#04x} received", number); + if (has_error_code(static_cast(number))) + { + kstd::println(kstd::print_sink::stderr, + "[x86_64:CPU] Unhandled exception number {:#04x} received with code {:#04x}", number, code); + } + else + { + kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled exception number {:#04x} received", number); + } } } - else if (number >= number_of_exception_vectors && - kapi::interrupts::dispatch(number) == kapi::interrupts::status::unhandled) + else { - kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x}", number); - } + auto irq_number = number - number_of_exception_vectors; - acknowledge_pic_interrupt(frame); + if (kapi::interrupts::dispatch(irq_number) == kapi::interrupts::status::unhandled) + { + kstd::println(kstd::print_sink::stderr, "[x86_64:CPU] Unhandled interrupt {:#04x} (IRQ{})", number, + irq_number); + } + + acknowledge_pic_interrupt(frame); + } } } -- cgit v1.2.3