Kernel/Interrupts: Return boolean on whether we handled the interrupt

If we are in a shared interrupt handler, the called handlers might
indicate it was not their interrupt, so we should not increment the
call counter of these handlers.

Kernel/ACPI/DynamicParser.cpp

@@ -17,7 +17,7 @@ UNMAP_AFTER_INIT DynamicParser::DynamicParser(PhysicalAddress rsdp)
     dmesgln("ACPI: Dynamic Parsing Enabled, Can parse AML");
 }
 
-void DynamicParser::handle_irq(const RegisterState&)
+bool DynamicParser::handle_irq(const RegisterState&)
 {
     // FIXME: Implement IRQ handling of ACPI signals!
     VERIFY_NOT_REACHED();

Kernel/ACPI/DynamicParser.h

@@ -36,7 +36,7 @@ protected:
 private:
     void build_namespace();
     // ^IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     OwnPtr<Region> m_acpi_namespace;
 };

Kernel/Devices/HID/I8042Controller.cpp

@@ -129,25 +129,26 @@ UNMAP_AFTER_INIT void I8042Controller::detect_devices()
         m_mouse_device->enable_interrupts();
 }
 
-void I8042Controller::irq_process_input_buffer(HIDDevice::Type)
+bool I8042Controller::irq_process_input_buffer(HIDDevice::Type)
 {
     VERIFY(Processor::current().in_irq());
 
     u8 status = IO::in8(I8042_STATUS);
     if (!(status & I8042_BUFFER_FULL))
-        return;
+        return false;
     HIDDevice::Type data_for_device = ((status & I8042_WHICH_BUFFER) == I8042_MOUSE_BUFFER) ? HIDDevice::Type::Mouse : HIDDevice::Type::Keyboard;
     u8 byte = IO::in8(I8042_BUFFER);
     if (data_for_device == HIDDevice::Type::Mouse) {
         VERIFY(m_mouse_device);
         static_cast<PS2MouseDevice&>(*m_mouse_device).irq_handle_byte_read(byte);
-        return;
+        return true;
     }
     if (data_for_device == HIDDevice::Type::Keyboard) {
         VERIFY(m_keyboard_device);
         static_cast<PS2KeyboardDevice&>(*m_keyboard_device).irq_handle_byte_read(byte);
-        return;
+        return true;
     }
+    return false;
 }
 
 void I8042Controller::do_drain()

Kernel/Devices/HID/I8042Controller.h

@@ -89,7 +89,7 @@ public:
     void prepare_for_output();
     void prepare_for_input(HIDDevice::Type);
 
-    void irq_process_input_buffer(HIDDevice::Type);
+    bool irq_process_input_buffer(HIDDevice::Type);
 
     RefPtr<MouseDevice> mouse() const;
     RefPtr<KeyboardDevice> keyboard() const;

Kernel/Devices/HID/PS2KeyboardDevice.cpp

@@ -85,11 +85,11 @@ void PS2KeyboardDevice::irq_handle_byte_read(u8 byte)
     }
 }
 
-void PS2KeyboardDevice::handle_irq(const RegisterState&)
+bool PS2KeyboardDevice::handle_irq(const RegisterState&)
 {
     // The controller will read the data and call irq_handle_byte_read
     // for the appropriate device
-    m_i8042_controller->irq_process_input_buffer(HIDDevice::Type::Keyboard);
+    return m_i8042_controller->irq_process_input_buffer(HIDDevice::Type::Keyboard);
 }
 
 UNMAP_AFTER_INIT RefPtr<PS2KeyboardDevice> PS2KeyboardDevice::try_to_initialize(const I8042Controller& ps2_controller)

Kernel/Devices/HID/PS2KeyboardDevice.h

@@ -39,7 +39,7 @@ private:
     explicit PS2KeyboardDevice(const I8042Controller&);
 
     // ^IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     // ^CharacterDevice
     virtual const char* class_name() const override { return "KeyboardDevice"; }

Kernel/Devices/HID/PS2MouseDevice.cpp

@@ -40,11 +40,11 @@ UNMAP_AFTER_INIT PS2MouseDevice::~PS2MouseDevice()
 {
 }
 
-void PS2MouseDevice::handle_irq(const RegisterState&)
+bool PS2MouseDevice::handle_irq(const RegisterState&)
 {
     // The controller will read the data and call irq_handle_byte_read
     // for the appropriate device
-    m_i8042_controller->irq_process_input_buffer(instrument_type());
+    return m_i8042_controller->irq_process_input_buffer(instrument_type());
 }
 
 void PS2MouseDevice::irq_handle_byte_read(u8 byte)

Kernel/Devices/HID/PS2MouseDevice.h

@@ -35,7 +35,7 @@ public:
 protected:
     explicit PS2MouseDevice(const I8042Controller&);
     // ^IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     struct RawPacket {
         union {

Kernel/Devices/SB16.cpp

@@ -205,8 +205,10 @@ void SB16::dma_start(uint32_t length)
     IO::out8(0xd4, (channel % 4));
 }
 
-void SB16::handle_irq(const RegisterState&)
+bool SB16::handle_irq(const RegisterState&)
 {
+    // FIXME: Check if the interrupt was actually for us or not... (shared IRQs)
+
     // Stop sound output ready for the next block.
     dsp_write(0xd5);
 
@@ -215,6 +217,7 @@ void SB16::handle_irq(const RegisterState&)
         IO::in8(DSP_R_ACK); // 16 bit interrupt
 
     m_irq_queue.wake_all();
+    return true;
 }
 
 void SB16::wait_for_irq()

Kernel/Devices/SB16.h

@@ -40,7 +40,7 @@ public:
 
 private:
     // ^IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     // ^CharacterDevice
     virtual const char* class_name() const override { return "SB16"; }

Kernel/Devices/USB/UHCIController.cpp

@@ -586,13 +586,13 @@ void UHCIController::spawn_port_proc()
     });
 }
 
-void UHCIController::handle_irq(const RegisterState&)
+bool UHCIController::handle_irq(const RegisterState&)
 {
     u32 status = read_usbsts();
 
     // Shared IRQ. Not ours!
     if (!status)
-        return;
+        return false;
 
     if constexpr (UHCI_DEBUG) {
         dbgln("UHCI: Interrupt happened!");
@@ -601,6 +601,7 @@ void UHCIController::handle_irq(const RegisterState&)
 
     // Write back USBSTS to clear bits
     write_usbsts(status);
+    return true;
 }
 
 }

Kernel/Devices/USB/UHCIController.h

@@ -60,7 +60,7 @@ private:
     void write_portsc1(u16 value) { m_io_base.offset(0x10).out(value); }
     void write_portsc2(u16 value) { m_io_base.offset(0x12).out(value); }
 
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     void create_structures();
     void setup_schedule();

Kernel/Interrupts/APIC.cpp

@@ -70,7 +70,7 @@ public:
         handler->register_interrupt_handler();
     }
 
-    virtual void handle_interrupt(const RegisterState&) override;
+    virtual bool handle_interrupt(const RegisterState&) override;
 
     virtual bool eoi() override;
 
@@ -101,7 +101,7 @@ public:
         handler->register_interrupt_handler();
     }
 
-    virtual void handle_interrupt(const RegisterState&) override;
+    virtual bool handle_interrupt(const RegisterState&) override;
 
     virtual bool eoi() override;
 
@@ -555,9 +555,10 @@ u32 APIC::get_timer_divisor()
     return 16;
 }
 
-void APICIPIInterruptHandler::handle_interrupt(const RegisterState&)
+bool APICIPIInterruptHandler::handle_interrupt(const RegisterState&)
 {
     dbgln_if(APIC_SMP_DEBUG, "APIC IPI on CPU #{}", Processor::id());
+    return true;
 }
 
 bool APICIPIInterruptHandler::eoi()
@@ -567,9 +568,10 @@ bool APICIPIInterruptHandler::eoi()
     return true;
 }
 
-void APICErrInterruptHandler::handle_interrupt(const RegisterState&)
+bool APICErrInterruptHandler::handle_interrupt(const RegisterState&)
 {
     dbgln("APIC: SMP error on CPU #{}", Processor::id());
+    return true;
 }
 
 bool APICErrInterruptHandler::eoi()

Kernel/Interrupts/GenericInterruptHandler.h

@@ -27,7 +27,9 @@ public:
     {
         VERIFY(!m_registered);
     }
-    virtual void handle_interrupt(const RegisterState& regs) = 0;
+    // Note: this method returns boolean value, to indicate if the handler handled
+    // the interrupt or not. This is useful for shared handlers mostly.
+    virtual bool handle_interrupt(const RegisterState& regs) = 0;
 
     void will_be_destroyed();
     bool is_registered() const { return m_registered; }

Kernel/Interrupts/IRQHandler.h

@@ -19,8 +19,8 @@ class IRQHandler : public GenericInterruptHandler {
 public:
     virtual ~IRQHandler();
 
-    virtual void handle_interrupt(const RegisterState& regs) { handle_irq(regs); }
-    virtual void handle_irq(const RegisterState&) = 0;
+    virtual bool handle_interrupt(const RegisterState& regs) { return handle_irq(regs); }
+    virtual bool handle_irq(const RegisterState&) = 0;
 
     void enable_irq();
     void disable_irq();

Kernel/Interrupts/SharedIRQHandler.cpp

@@ -63,7 +63,7 @@ SharedIRQHandler::~SharedIRQHandler()
     disable_interrupt_vector();
 }
 
-void SharedIRQHandler::handle_interrupt(const RegisterState& regs)
+bool SharedIRQHandler::handle_interrupt(const RegisterState& regs)
 {
     VERIFY_INTERRUPTS_DISABLED();
 
@@ -71,16 +71,19 @@ void SharedIRQHandler::handle_interrupt(const RegisterState& regs)
         dbgln("Interrupt @ {}", interrupt_number());
         dbgln("Interrupt Handlers registered - {}", m_handlers.size());
     }
-
     int i = 0;
+    bool was_handled = false;
     for (auto* handler : m_handlers) {
         dbgln_if(INTERRUPT_DEBUG, "Going for Interrupt Handling @ {}, Shared Interrupt {}", i, interrupt_number());
         VERIFY(handler != nullptr);
-        handler->increment_invoking_counter();
-        handler->handle_interrupt(regs);
+        if (handler->handle_interrupt(regs)) {
+            handler->increment_invoking_counter();
+            was_handled = true;
+        }
         dbgln_if(INTERRUPT_DEBUG, "Going for Interrupt Handling @ {}, Shared Interrupt {} - End", i, interrupt_number());
         i++;
     }
+    return was_handled;
 }
 
 void SharedIRQHandler::enable_interrupt_vector()

Kernel/Interrupts/SharedIRQHandler.h

@@ -19,7 +19,7 @@ class SharedIRQHandler final : public GenericInterruptHandler {
 public:
     static void initialize(u8 interrupt_number);
     virtual ~SharedIRQHandler();
-    virtual void handle_interrupt(const RegisterState& regs) override;
+    virtual bool handle_interrupt(const RegisterState& regs) override;
 
     void register_handler(GenericInterruptHandler&);
     void unregister_handler(GenericInterruptHandler&);

Kernel/Interrupts/SpuriousInterruptHandler.cpp

@@ -54,16 +54,19 @@ SpuriousInterruptHandler::~SpuriousInterruptHandler()
 {
 }
 
-void SpuriousInterruptHandler::handle_interrupt(const RegisterState& state)
+bool SpuriousInterruptHandler::handle_interrupt(const RegisterState& state)
 {
     // Actually check if IRQ7 or IRQ15 are spurious, and if not, call the real handler to handle the IRQ.
     if (m_responsible_irq_controller->get_isr() & (1 << interrupt_number())) {
         m_real_irq = true; // remember that we had a real IRQ, when EOI later!
-        m_real_handler->increment_invoking_counter();
-        m_real_handler->handle_interrupt(state);
-        return;
+        if (m_real_handler->handle_interrupt(state)) {
+            m_real_handler->increment_invoking_counter();
+            return true;
+        }
+        return false;
     }
     dbgln("Spurious interrupt, vector {}", interrupt_number());
+    return true;
 }
 
 void SpuriousInterruptHandler::enable_interrupt_vector()

Kernel/Interrupts/SpuriousInterruptHandler.h

@@ -18,7 +18,7 @@ class SpuriousInterruptHandler final : public GenericInterruptHandler {
 public:
     static void initialize(u8 interrupt_number);
     virtual ~SpuriousInterruptHandler();
-    virtual void handle_interrupt(const RegisterState& regs) override;
+    virtual bool handle_interrupt(const RegisterState& regs) override;
 
     void register_handler(GenericInterruptHandler&);
     void unregister_handler(GenericInterruptHandler&);

Kernel/Interrupts/UnhandledInterruptHandler.cpp

@@ -13,7 +13,7 @@ UnhandledInterruptHandler::UnhandledInterruptHandler(u8 interrupt_vector)
 {
 }
 
-void UnhandledInterruptHandler::handle_interrupt(const RegisterState&)
+bool UnhandledInterruptHandler::handle_interrupt(const RegisterState&)
 {
     PANIC("Interrupt: Unhandled vector {} was invoked for handle_interrupt(RegisterState&).", interrupt_number());
 }

Kernel/Interrupts/UnhandledInterruptHandler.h

@@ -17,7 +17,7 @@ public:
     explicit UnhandledInterruptHandler(u8 interrupt_vector);
     virtual ~UnhandledInterruptHandler();
 
-    virtual void handle_interrupt(const RegisterState&) override;
+    virtual bool handle_interrupt(const RegisterState&) override;
 
     [[noreturn]] virtual bool eoi() override;
 

Kernel/Net/E1000NetworkAdapter.cpp

@@ -230,12 +230,15 @@ UNMAP_AFTER_INIT E1000NetworkAdapter::~E1000NetworkAdapter()
 {
 }
 
-void E1000NetworkAdapter::handle_irq(const RegisterState&)
+bool E1000NetworkAdapter::handle_irq(const RegisterState&)
 {
     u32 status = in32(REG_INTERRUPT_CAUSE_READ);
 
     m_entropy_source.add_random_event(status);
 
+    if (status == 0)
+        return false;
+
     if (status & INTERRUPT_LSC) {
         u32 flags = in32(REG_CTRL);
         out32(REG_CTRL, flags | ECTRL_SLU);
@@ -253,6 +256,7 @@ void E1000NetworkAdapter::handle_irq(const RegisterState&)
     m_wait_queue.wake_all();
 
     out32(REG_INTERRUPT_CAUSE_READ, 0xffffffff);
+    return true;
 }
 
 UNMAP_AFTER_INIT void E1000NetworkAdapter::detect_eeprom()

Kernel/Net/E1000NetworkAdapter.h

@@ -36,7 +36,7 @@ protected:
     void setup_link();
 
     E1000NetworkAdapter(PCI::Address, u8 irq);
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
     virtual const char* class_name() const override { return "E1000NetworkAdapter"; }
 
     struct [[gnu::packed]] e1000_rx_desc {

Kernel/Net/NE2000NetworkAdapter.cpp

@@ -184,10 +184,13 @@ UNMAP_AFTER_INIT NE2000NetworkAdapter::~NE2000NetworkAdapter()
 {
 }
 
-void NE2000NetworkAdapter::handle_irq(const RegisterState&)
+bool NE2000NetworkAdapter::handle_irq(const RegisterState&)
 {
     u8 status = in8(REG_RW_INTERRUPTSTATUS);
     dbgln_if(NE2000_DEBUG, "NE2000NetworkAdapter: Got interrupt, status={:#02x}", status);
+    if (status == 0) {
+        return false;
+    }
 
     if (status & BIT_INTERRUPTMASK_PRX) {
         dbgln_if(NE2000_DEBUG, "NE2000NetworkAdapter: Interrupt for packet received");
@@ -223,6 +226,7 @@ void NE2000NetworkAdapter::handle_irq(const RegisterState&)
     m_wait_queue.wake_all();
 
     out8(REG_RW_INTERRUPTSTATUS, status);
+    return true;
 }
 
 UNMAP_AFTER_INIT int NE2000NetworkAdapter::ram_test()

Kernel/Net/NE2000NetworkAdapter.h

@@ -29,7 +29,7 @@ public:
 
 private:
     NE2000NetworkAdapter(PCI::Address, u8 irq);
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
     virtual const char* class_name() const override { return "NE2000NetworkAdapter"; }
 
     int ram_test();

Kernel/Net/RTL8139NetworkAdapter.cpp

@@ -155,8 +155,9 @@ UNMAP_AFTER_INIT RTL8139NetworkAdapter::~RTL8139NetworkAdapter()
 {
 }
 
-void RTL8139NetworkAdapter::handle_irq(const RegisterState&)
+bool RTL8139NetworkAdapter::handle_irq(const RegisterState&)
 {
+    bool was_handled = false;
     for (;;) {
         int status = in16(REG_ISR);
         out16(REG_ISR, status);
@@ -168,6 +169,7 @@ void RTL8139NetworkAdapter::handle_irq(const RegisterState&)
         if ((status & (INT_RXOK | INT_RXERR | INT_TXOK | INT_TXERR | INT_RX_BUFFER_OVERFLOW | INT_LINK_CHANGE | INT_RX_FIFO_OVERFLOW | INT_LENGTH_CHANGE | INT_SYSTEM_ERROR)) == 0)
             break;
 
+        was_handled = true;
         if (status & INT_RXOK) {
             dbgln_if(RTL8139_DEBUG, "RTL8139: RX ready");
             receive();
@@ -201,6 +203,7 @@ void RTL8139NetworkAdapter::handle_irq(const RegisterState&)
             reset();
         }
     }
+    return was_handled;
 }
 
 void RTL8139NetworkAdapter::reset()

Kernel/Net/RTL8139NetworkAdapter.h

@@ -31,7 +31,7 @@ public:
 
 private:
     RTL8139NetworkAdapter(PCI::Address, u8 irq);
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
     virtual const char* class_name() const override { return "RTL8139NetworkAdapter"; }
 
     void reset();

Kernel/Net/RTL8168NetworkAdapter.cpp

@@ -1073,8 +1073,9 @@ UNMAP_AFTER_INIT RTL8168NetworkAdapter::~RTL8168NetworkAdapter()
 {
 }
 
-void RTL8168NetworkAdapter::handle_irq(const RegisterState&)
+bool RTL8168NetworkAdapter::handle_irq(const RegisterState&)
 {
+    bool was_handled = false;
     for (;;) {
         int status = in16(REG_ISR);
         out16(REG_ISR, status);
@@ -1086,6 +1087,7 @@ void RTL8168NetworkAdapter::handle_irq(const RegisterState&)
         if ((status & (INT_RXOK | INT_RXERR | INT_TXOK | INT_TXERR | INT_RX_OVERFLOW | INT_LINK_CHANGE | INT_RX_FIFO_OVERFLOW | INT_SYS_ERR)) == 0)
             break;
 
+        was_handled = true;
         if (status & INT_RXOK) {
             dbgln_if(RTL8168_DEBUG, "RTL8168: RX ready");
             receive();
@@ -1116,6 +1118,7 @@ void RTL8168NetworkAdapter::handle_irq(const RegisterState&)
             dmesgln("RTL8168: Fatal system error");
         }
     }
+    return was_handled;
 }
 
 void RTL8168NetworkAdapter::reset()

Kernel/Net/RTL8168NetworkAdapter.h

@@ -36,7 +36,7 @@ private:
 
     RTL8168NetworkAdapter(PCI::Address, u8 irq);
 
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
     virtual const char* class_name() const override { return "RTL8168NetworkAdapter"; }
 
     struct [[gnu::packed]] TXDescriptor {

Kernel/Storage/AHCI.h

@@ -158,6 +158,11 @@ public:
         return m_bitfield & ((1 << port_index) & m_bit_mask);
     }
 
+    bool is_zeroed() const
+    {
+        return (m_bitfield & m_bit_mask) == 0;
+    }
+
     Vector<u8> to_vector() const
     {
         // FIXME: Add a sync mechanism!

Kernel/Storage/AHCIPortHandler.cpp

@@ -82,9 +82,11 @@ AHCIPortHandler::~AHCIPortHandler()
 {
 }
 
-void AHCIPortHandler::handle_irq(const RegisterState&)
+bool AHCIPortHandler::handle_irq(const RegisterState&)
 {
     dbgln_if(AHCI_DEBUG, "AHCI Port Handler: IRQ received");
+    if (m_pending_ports_interrupts.is_zeroed())
+        return false;
     for (auto port_index : m_pending_ports_interrupts.to_vector()) {
         auto port = m_handled_ports.get(port_index);
         VERIFY(port.has_value());
@@ -93,6 +95,7 @@ void AHCIPortHandler::handle_irq(const RegisterState&)
         // We do this to clear the pending interrupt after we handled it.
         m_pending_ports_interrupts.set_at(port_index);
     }
+    return true;
 }
 
 }

Kernel/Storage/AHCIPortHandler.h

@@ -48,7 +48,7 @@ private:
     UNMAP_AFTER_INIT AHCIPortHandler(AHCIController&, u8 irq, AHCI::MaskedBitField taken_ports);
 
     //^ IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     enum class Direction : u8 {
         Read,

Kernel/Storage/BMIDEChannel.cpp

@@ -63,7 +63,7 @@ static void print_ide_status(u8 status)
         (status & ATA_SR_ERR) != 0);
 }
 
-void BMIDEChannel::handle_irq(const RegisterState&)
+bool BMIDEChannel::handle_irq(const RegisterState&)
 {
     u8 status = m_io_group.io_base().offset(ATA_REG_STATUS).in<u8>();
 
@@ -74,7 +74,7 @@ void BMIDEChannel::handle_irq(const RegisterState&)
     if (!(bstatus & 0x4)) {
         // interrupt not from this device, ignore
         dbgln_if(PATA_DEBUG, "BMIDEChannel: ignore interrupt");
-        return;
+        return false;
     }
     // clear bus master interrupt status
     m_io_group.bus_master_base().value().offset(2).out<u8>(m_io_group.bus_master_base().value().offset(2).in<u8>() | 4);
@@ -87,7 +87,7 @@ void BMIDEChannel::handle_irq(const RegisterState&)
 
     if (!m_current_request) {
         dbgln("BMIDEChannel: IRQ but no pending request!");
-        return;
+        return false;
     }
 
     if (status & ATA_SR_ERR) {
@@ -96,10 +96,11 @@ void BMIDEChannel::handle_irq(const RegisterState&)
         dbgln("BMIDEChannel: Error {:#02x}!", (u8)m_device_error);
         try_disambiguate_error();
         complete_current_request(AsyncDeviceRequest::Failure);
-        return;
+        return true;
     }
     m_device_error = 0;
     complete_current_request(AsyncDeviceRequest::Success);
+    return true;
 }
 
 void BMIDEChannel::complete_current_request(AsyncDeviceRequest::RequestResult result)

Kernel/Storage/BMIDEChannel.h

@@ -39,7 +39,7 @@ private:
     void complete_current_request(AsyncDeviceRequest::RequestResult);
 
     //^ IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     //* IDEChannel
     virtual void send_ata_io_command(LBAMode lba_mode, Direction direction) const;

Kernel/Storage/IDEChannel.cpp

@@ -190,7 +190,7 @@ void IDEChannel::try_disambiguate_error()
     }
 }
 
-void IDEChannel::handle_irq(const RegisterState&)
+bool IDEChannel::handle_irq(const RegisterState&)
 {
     u8 status = m_io_group.io_base().offset(ATA_REG_STATUS).in<u8>();
 
@@ -204,7 +204,7 @@ void IDEChannel::handle_irq(const RegisterState&)
 
     if (!m_current_request) {
         dbgln("IDEChannel: IRQ but no pending request!");
-        return;
+        return false;
     }
 
     if (status & ATA_SR_ERR) {
@@ -213,7 +213,7 @@ void IDEChannel::handle_irq(const RegisterState&)
         dbgln("IDEChannel: Error {:#02x}!", (u8)m_device_error);
         try_disambiguate_error();
         complete_current_request(AsyncDeviceRequest::Failure);
-        return;
+        return true;
     }
     m_device_error = 0;
 
@@ -251,6 +251,7 @@ void IDEChannel::handle_irq(const RegisterState&)
             }
         }
     });
+    return true;
 }
 
 static void io_delay()

Kernel/Storage/IDEChannel.h

@@ -122,7 +122,7 @@ protected:
     IDEChannel(const IDEController&, IOAddressGroup, ChannelType type);
     IDEChannel(const IDEController&, u8 irq, IOAddressGroup, ChannelType type);
     //^ IRQHandler
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     virtual void send_ata_io_command(LBAMode lba_mode, Direction direction) const;
 

Kernel/Time/HPETComparator.cpp

@@ -51,11 +51,12 @@ void HPETComparator::set_non_periodic()
     HPET::the().disable_periodic_interrupt(*this);
 }
 
-void HPETComparator::handle_irq(const RegisterState& regs)
+bool HPETComparator::handle_irq(const RegisterState& regs)
 {
-    HardwareTimer::handle_irq(regs);
+    auto result = HardwareTimer::handle_irq(regs);
     if (!is_periodic())
         set_new_countdown();
+    return result;
 }
 
 void HPETComparator::set_new_countdown()

Kernel/Time/HPETComparator.h

@@ -43,7 +43,7 @@ public:
 
 private:
     void set_new_countdown();
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
     HPETComparator(u8 number, u8 irq, bool periodic_capable, bool is_64bit_capable);
     bool m_periodic : 1;
     bool m_periodic_capable : 1;

Kernel/Time/HardwareTimer.h

@@ -92,10 +92,14 @@ protected:
     {
     }
 
-    virtual void handle_irq(const RegisterState& regs) override
+    virtual bool handle_irq(const RegisterState& regs) override
     {
-        if (m_callback)
+        // Note: if we have an IRQ on this line, it's going to be the timer always
+        if (m_callback) {
             m_callback(regs);
+            return true;
+        }
+        return false;
     }
 
     u64 m_frequency { OPTIMAL_TICKS_PER_SECOND_RATE };
@@ -142,10 +146,14 @@ protected:
     {
     }
 
-    virtual void handle_interrupt(const RegisterState& regs) override
+    virtual bool handle_interrupt(const RegisterState& regs) override
     {
-        if (m_callback)
+        // Note: if we have an IRQ on this line, it's going to be the timer always
+        if (m_callback) {
             m_callback(regs);
+            return true;
+        }
+        return false;
     }
 
     u64 m_frequency { OPTIMAL_TICKS_PER_SECOND_RATE };

Kernel/Time/RTC.cpp

@@ -27,10 +27,11 @@ RealTimeClock::RealTimeClock(Function<void(const RegisterState&)> callback)
     CMOS::write(0x8B, CMOS::read(0xB) | 0x40);
     reset_to_default_ticks_per_second();
 }
-void RealTimeClock::handle_irq(const RegisterState& regs)
+bool RealTimeClock::handle_irq(const RegisterState& regs)
 {
-    HardwareTimer::handle_irq(regs);
+    auto result = HardwareTimer::handle_irq(regs);
     CMOS::read(0x8C);
+    return result;
 }
 
 size_t RealTimeClock::ticks_per_second() const

Kernel/Time/RTC.h

@@ -31,6 +31,6 @@ public:
 
 private:
     explicit RealTimeClock(Function<void(const RegisterState&)> callback);
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 };
 }

Kernel/VirtIO/VirtIO.cpp

@@ -342,11 +342,13 @@ u8 VirtIODevice::isr_status()
     return config_read8(*m_isr_cfg, 0);
 }
 
-void VirtIODevice::handle_irq(const RegisterState&)
+bool VirtIODevice::handle_irq(const RegisterState&)
 {
     u8 isr_type = isr_status();
-    if ((isr_type & (QUEUE_INTERRUPT | DEVICE_CONFIG_INTERRUPT)) == 0)
+    if ((isr_type & (QUEUE_INTERRUPT | DEVICE_CONFIG_INTERRUPT)) == 0) {
         dbgln_if(VIRTIO_DEBUG, "{}: Handling interrupt with unknown type: {}", m_class_name, isr_type);
+        return false;
+    }
     if (isr_type & DEVICE_CONFIG_INTERRUPT) {
         dbgln_if(VIRTIO_DEBUG, "{}: VirtIO Device config interrupt!", m_class_name);
         if (!handle_device_config_change()) {
@@ -357,11 +359,14 @@ void VirtIODevice::handle_irq(const RegisterState&)
     if (isr_type & QUEUE_INTERRUPT) {
         dbgln_if(VIRTIO_DEBUG, "{}: VirtIO Queue interrupt!", m_class_name);
         for (size_t i = 0; i < m_queues.size(); i++) {
-            if (get_queue(i).new_data_available())
-                return handle_queue_update(i);
+            if (get_queue(i).new_data_available()) {
+                handle_queue_update(i);
+                return true;
+            }
         }
         dbgln_if(VIRTIO_DEBUG, "{}: Got queue interrupt but all queues are up to date!", m_class_name);
     }
+    return true;
 }
 
 void VirtIODevice::supply_chain_and_notify(u16 queue_index, VirtIOQueueChain& chain)

Kernel/VirtIO/VirtIO.h

@@ -222,7 +222,7 @@ private:
     void reset_device();
 
     u8 isr_status();
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     NonnullOwnPtrVector<VirtIOQueue> m_queues;
     NonnullOwnPtrVector<Configuration> m_configs;