Account for the case when distance information is not available

src/acpi/srat/aarch64.rs

@@ -0,0 +1,5 @@
+use crate::acpi::srat::Srat;
+
+pub fn init_srat(srat: &Srat) {
+    // todo
+}

src/acpi/srat/mod.rs

@@ -77,11 +77,10 @@ impl<'a> Iterator for SratIter<'a> {
                     *(entry.add(2) as *const GiccAffinity)
                 }),
                 // ignore GIC ITS Affinity and Generic Initiator Affinity
-                4 | 5 => {
+                _ => {
                     self.i += entry_len as u32;
                     continue;
                 }
-                _ => SratEntry::Unknown(unsafe { *entry }),
             });
             self.i += entry_len as u32;
             return entry;
@@ -97,8 +96,7 @@ pub enum SratEntry {
     ProcessorLocalAffinity(ProcessorLocalAffinity),
     GiccAffinity(GiccAffinity),
     // unimplemented: Gic Its Affinity and Generic Initiator Affinity
-    //  our current focus is only on memory and cpus
-    Unknown(u8),
+    // our current focus is only on memory and cpus
 }
 
 #[repr(C, packed)]
@@ -144,3 +142,17 @@ struct GiccAffinity {
     flags: u32,
     clock_domain: u32,
 }
+
+#[inline(always)]
+pub(crate) fn to_usize(low: u32, high: u32) -> usize {
+    #[cfg(target_pointer_width = "32")]
+    return low as usize;
+
+    #[cfg(target_pointer_width = "64")]
+    {
+        let mut low_and_high = [0u8; 8];
+        low_and_high[0..=3].copy_from_slice(low.to_le_bytes().as_slice());
+        low_and_high[4..=7].copy_from_slice(high.to_le_bytes().as_slice());
+        usize::from_le_bytes(low_and_high)
+    }
+}

src/acpi/srat/x86.rs

@@ -1,24 +1,10 @@
 use core::iter;
 
 use crate::{
-    acpi::srat::{Srat, SratEntry},
+    acpi::srat::{to_usize, Srat, SratEntry},
     numa::{self, NUMA_NODES},
 };
 
-#[inline(always)]
-fn to_usize(low: u32, high: u32) -> usize {
-    #[cfg(target_pointer_width = "32")]
-    return low as usize;
-
-    #[cfg(target_pointer_width = "64")]
-    {
-        let mut low_and_high = [0u8; 8];
-        low_and_high[0..=3].copy_from_slice(low.to_le_bytes().as_slice());
-        low_and_high[4..=7].copy_from_slice(high.to_le_bytes().as_slice());
-        usize::from_le_bytes(low_and_high)
-    }
-}
-
 #[inline(always)]
 fn to_single_int(high: &[u8; 3], low: u8) -> u32 {
     let mut high_and_low = [0u8; 4];

src/numa.rs

@@ -54,7 +54,8 @@ pub fn init() {
     #[cfg(any(target_arch = "riscv64", target_arch = "aarch64"))]
     {
         if !flag {
-            todo!()
+            // todo!()
+            return;
         }
     }
 
@@ -160,20 +161,42 @@ fn put_for_adoption(
     distances: Vec<(u32, u8)>,
     memories: Option<Vec<NumaMemory>>,
     cpus: Option<Vec<NumaCpu>>,
-    orphan_node_id: u32,
+    orphan_node_id: u32, // id of the node containing only memory / CPU (orphan)
 ) {
     if let Some(memories) = memories {
         assert!(cpus.is_none());
-        let (nearest_node_id, distance) = distances.first().unwrap();
-        let nearest_node = nodes.get_mut(nearest_node_id).unwrap();
-        nearest_node.memory.extend(memories);
+        let foster_node = if !distances.is_empty() {
+            let (nearest_node_id, distance) = distances.first().unwrap();
+            nodes.get_mut(nearest_node_id).unwrap()
+        } else {
+            let foster_node_id = {
+                let mut node_ids = nodes.keys();
+                let foster_node = node_ids
+                    .find(|node_id| **node_id != orphan_node_id)
+                    .unwrap();
+                *foster_node
+            };
+            nodes.get_mut(&foster_node_id).unwrap() // panic not possible since there must be atleast one other domain with a cpu
+        };
+        foster_node.memory.extend(memories);
     } else if let Some(cpus) = cpus {
         assert!(memories.is_none());
-        let (nearest_node_id, distance) = distances.first().unwrap();
-        let nearest_node = nodes.get_mut(nearest_node_id).unwrap();
-        nearest_node.cpus.extend(cpus);
+        let foster_node = if !distances.is_empty() {
+            let (nearest_node_id, distance) = distances.first().unwrap();
+            nodes.get_mut(nearest_node_id).unwrap()
+        } else {
+            let foster_node_id = {
+                let mut node_ids = nodes.keys();
+                let foster_node = node_ids
+                    .find(|node_id| **node_id != orphan_node_id)
+                    .unwrap();
+                *foster_node
+            };
+            nodes.get_mut(&foster_node_id).unwrap() // panic not possible since there must be atleast one other domain with memory
+        };
+        foster_node.cpus.extend(cpus);
     } else {
-        panic!()
+        unreachable!() // this should never happen
     };
 
     for (_, node) in nodes {

src/startup/mod.rs

@@ -9,7 +9,8 @@ use crate::{
     arch::interrupt,
     context::{self, switch::SwitchResult},
     memory::{PhysicalAddress, RmmA, RmmArch},
-    numa, profiling, scheme,
+    numa::{self, NUMA_NODES},
+    profiling, scheme,
     sync::CleanLockToken,
 };