--- a/src/arch/x86_shared/idt.rs
+++ b/src/arch/x86_shared/idt.rs
@@ -110,6 +110,8 @@
 }
 
 pub fn available_irqs_iter(cpu_id: LogicalCpuId) -> impl Iterator<Item = u8> + 'static {
+    let count = (32..=254).filter(|&index| !is_reserved(cpu_id, index)).count();
+    info!("available_irqs_iter: cpu_id={} count={}", cpu_id.get(), count);
     (32..=254).filter(move |&index| !is_reserved(cpu_id, index))
 }
 
--- a/src/scheme/irq.rs
+++ b/src/scheme/irq.rs
@@ -83,7 +83,7 @@
 #[allow(dead_code)]
 enum Handle {
     SchemeRoot,
-    Irq { ack: AtomicUsize, irq: u8 },
+    Irq { ack: AtomicUsize, irq: u8, cpu_id: LogicalCpuId },
     Avail(LogicalCpuId),
     TopLevel,
     Phandle(u8, Vec<u8>),
@@ -93,7 +93,7 @@
 impl Handle {
     fn as_irq_handle(&self) -> Option<(&AtomicUsize, u8)> {
         match self {
-            &Self::Irq { ref ack, irq } => Some((ack, irq)),
+            &Self::Irq { ref ack, irq, cpu_id: _ } => Some((ack, irq)),
             _ => None,
         }
     }
@@ -147,6 +147,7 @@
                     Handle::Irq {
                         ack: AtomicUsize::new(0),
                         irq: irq_number,
+                        cpu_id: LogicalCpuId::BSP,
                     },
                     InternalFlags::empty(),
                 )
@@ -165,6 +166,7 @@
                     Handle::Irq {
                         ack: AtomicUsize::new(0),
                         irq: irq_number,
+                        cpu_id,
                     },
                     InternalFlags::empty(),
                 )
@@ -206,6 +208,7 @@
                     Handle::Irq {
                         ack: AtomicUsize::new(0),
                         irq: irq_number as u8,
+                        cpu_id: LogicalCpuId::new(0),
                     },
                     InternalFlags::empty(),
                 )
@@ -349,6 +352,7 @@
                     Handle::Irq {
                         ack: AtomicUsize::new(0),
                         irq: plain_irq_number,
+                        cpu_id: LogicalCpuId::BSP,
                     },
                     InternalFlags::empty(),
                 )
@@ -404,6 +408,7 @@
                 }
             }
             Handle::Avail(cpu_id) => {
+                let mut listed = 0;
                 for vector in available_irqs_iter(cpu_id).skip(opaque) {
                     let irq = vector_to_irq(vector);
                     if cpu_id == LogicalCpuId::BSP && irq < BASE_IRQ_COUNT {
@@ -417,7 +422,9 @@
                         name: &intermediate,
                         next_opaque_id: u64::from(vector) + 1,
                     })?;
+                    listed += 1;
                 }
+                info!("irq getdents Avail: cpu_id={} opaque={} listed={}", cpu_id.get(), opaque, listed);
             }
             _ => return Err(Error::new(ENOTDIR)),
         }
@@ -452,11 +459,14 @@
         let handle = handles_guard.get(id)?;
 
         if let &Handle::Irq {
-            irq: handle_irq, ..
+            irq: handle_irq,
+            cpu_id: handle_cpu_id,
+            ..
         } = handle
             && handle_irq > BASE_IRQ_COUNT
         {
-            set_reserved(LogicalCpuId::BSP, irq_to_vector(handle_irq), false);
+            info!("irq close: unreserving vector {} on cpu_id={}", irq_to_vector(handle_irq), handle_cpu_id.get());
+            set_reserved(handle_cpu_id, irq_to_vector(handle_irq), false);
         }
         Ok(())
     }
@@ -497,6 +507,7 @@
             &Handle::Irq {
                 irq: handle_irq,
                 ack: ref handle_ack,
+                cpu_id: _,
             } => {
                 if buffer.len() < size_of::<usize>() {
                     return Err(Error::new(EINVAL));
@@ -611,6 +622,7 @@
             Handle::Irq {
                 irq: handle_irq,
                 ack: ref handle_ack,
+                cpu_id: _,
             } => {
                 if buffer.len() < size_of::<usize>() {
                     return Err(Error::new(EINVAL));