device_manager/aarch64: register intc on serial

We were missing registering the IrqChip on legacy serial devices,
which meant they couldn't trigger IRQs. This issue went under the
radar because only a few guests rely on them (so far, only NetBSD).

Let's fix it here.

Signed-off-by: Sergio Lopez <slp@redhat.com>

Author: slp

src/vmm/src/builder.rs

@@ -870,6 +870,7 @@ pub fn build_microvm(
             &vm,
             &mut mmio_device_manager,
             &mut kernel_cmdline,
+            intc.clone(),
             serial_devices,
         )?;
     }
@@ -1623,11 +1624,12 @@ fn attach_legacy_devices(
     vm: &Vm,
     mmio_device_manager: &mut MMIODeviceManager,
     kernel_cmdline: &mut kernel::cmdline::Cmdline,
+    intc: IrqChip,
     serial: Vec<Arc<Mutex<Serial>>>,
 ) -> std::result::Result<(), StartMicrovmError> {
     for s in serial {
         mmio_device_manager
-            .register_mmio_serial(vm.fd(), kernel_cmdline, s)
+            .register_mmio_serial(vm.fd(), kernel_cmdline, intc.clone(), s)
             .map_err(Error::RegisterMMIODevice)
             .map_err(StartMicrovmError::Internal)?;
     }

src/vmm/src/device_manager/kvm/mmio.rs

@@ -11,6 +11,8 @@ use std::{fmt, io};
 
 #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))]
 use devices::fdt::DeviceInfoForFDT;
+#[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))]
+use devices::legacy::IrqChip;
 use devices::{BusDevice, DeviceType};
 use kernel::cmdline as kernel_cmdline;
 use kvm_ioctls::{IoEventAddress, VmFd};
@@ -192,6 +194,7 @@ impl MMIODeviceManager {
         &mut self,
         vm: &VmFd,
         cmdline: &mut kernel_cmdline::Cmdline,
+        intc: IrqChip,
         serial: Arc<Mutex<devices::legacy::Serial>>,
     ) -> Result<()> {
         if self.irq > self.last_irq {
@@ -201,6 +204,8 @@ impl MMIODeviceManager {
         vm.register_irqfd(serial.lock().unwrap().interrupt_evt(), self.irq)
             .map_err(Error::RegisterIrqFd)?;
 
+        serial.lock().unwrap().set_intc(intc);
+
         self.bus
             .insert(serial, self.mmio_base, MMIO_LEN)
             .map_err(Error::BusError)?;