add QEMU pvpanic ISA device

bin/propolis-server/src/lib/initializer.rs

@@ -35,7 +35,7 @@ use crate::serial::Serial;
 use crate::server::CrucibleBackendMap;
 pub use nexus_client::Client as NexusClient;
 
-use anyhow::Result;
+use anyhow::{Context, Result};
 
 // Arbitrary ROM limit for now
 const MAX_ROM_SIZE: usize = 0x20_0000;
@@ -292,11 +292,9 @@ impl<'a> MachineInitializer<'a> {
                 if let Some(ref registry) = self.producer_registry {
                     let producer =
                         crate::stats::PvpanicProducer::new(uuid, pvpanic);
-                    registry.register_producer(producer).map_err(|error| {
-                        anyhow::anyhow!(
-                            "failed to register PVPANIC Oximeter producer: {error}"
-                        )
-                    })?;
+                    registry.register_producer(producer).context(
+                        "failed to register PVPANIC Oximeter producer",
+                    )?;
                 }
             }
         }

bin/propolis-server/src/lib/spec.rs

@@ -222,9 +222,13 @@ impl ServerSpecBuilder {
                 },
             )?;
 
-        let builder =
+        let mut builder =
             SpecBuilder::new(properties.vcpus, properties.memory, enable_pcie);
 
+        builder.add_pvpanic_device(components::devices::QemuPvpanic {
+            enable_isa: true,
+        })?;
+
         Ok(Self { builder })
     }
 

crates/propolis-api-types/src/instance_spec/v0/builder.rs

@@ -176,6 +176,22 @@ impl SpecBuilder {
         }
     }
 
+    /// Adds a QEMU pvpanic device.
+    pub fn add_pvpanic_device(
+        &mut self,
+        pvpanic: components::devices::QemuPvpanic,
+    ) -> Result<&Self, SpecBuilderError> {
+        if self.spec.devices.qemu_pvpanic.is_some() {
+            return Err(SpecBuilderError::DeviceNameInUse(
+                "pvpanic".to_string(),
+            ));
+        }
+
+        self.spec.devices.qemu_pvpanic = Some(pvpanic);
+
+        Ok(self)
+    }
+
     #[cfg(feature = "falcon")]
     pub fn set_softnpu_pci_port(
         &mut self,

crates/propolis-api-types/src/instance_spec/v0/mod.rs

@@ -113,6 +113,19 @@ pub struct DeviceSpecV0 {
     pub network_devices: HashMap<SpecKey, NetworkDeviceV0>,
     pub serial_ports: HashMap<SpecKey, components::devices::SerialPort>,
     pub pci_pci_bridges: HashMap<SpecKey, components::devices::PciPciBridge>,
+
+    /// This field has a default value (`None`) to allow for
+    /// backwards-compatibility when upgrading from a Propolis
+    /// version that does not support this device. If the pvpanic device was not
+    /// present in the spec being deserialized, a `None` will be produced,
+    /// rather than rejecting the spec.
+    #[serde(default)]
+    /// Skip serializing this field if it is `None`. This is so that Propolis
+    /// versions with support for this device are backwards-compatible with
+    /// older versions that don't, as long as the spec doesn't define a pvpanic
+    /// device --- if there is no panic device, skipping the field from the spec
+    /// means that the older version will still accept the spec.
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub qemu_pvpanic: Option<components::devices::QemuPvpanic>,
 
     #[cfg(feature = "falcon")]

openapi/propolis-server.json

@@ -625,6 +625,7 @@
           },
           "qemu_pvpanic": {
             "nullable": true,
+            "description": "This field has a default value (`None`) to allow for backwards-compatibility when upgrading from a Propolis version that does not support this device. If the pvpanic device was not present in the spec being deserialized, a `None` will be produced, rather than rejecting the spec. Skip serializing this field if it is `None`. This is so that Propolis versions with support for this device are backwards-compatible with older versions that don't, as long as the spec doesn't define a pvpanic device --- if there is no panic device, skipping the field from the spec means that the older version will still accept the spec.",
             "allOf": [
               {
                 "$ref": "#/components/schemas/QemuPvpanic"