diff --git a/src/mem/pagemap.h b/src/mem/pagemap.h
index 0774c68..5b78572 100644
--- a/src/mem/pagemap.h
+++ b/src/mem/pagemap.h
@@ -184,25 +184,35 @@ namespace snmalloc
       size_t shift = TOPLEVEL_SHIFT;
       std::atomic<PagemapEntry*>* e = &top[ix];
 
-      for (size_t i = 0; i < INDEX_LEVELS; i++)
+      // This is effectively a
+      //   for (size_t i = 0; i < INDEX_LEVELS; i++)
+      // loop, but uses constexpr to guarantee optimised version
+      // where the INDEX_LEVELS in {0,1}.
+      if constexpr (INDEX_LEVELS != 0)
       {
-        PagemapEntry* value = get_node<create_addr>(e, result);
-        if (unlikely(!result))
-          return {nullptr, 0};
-
-        shift -= BITS_PER_INDEX_LEVEL;
-        ix = (static_cast<size_t>(addr) >> shift) & ENTRIES_MASK;
-        e = &value->entries[ix];
-
-        if constexpr (INDEX_LEVELS == 1)
+        size_t i = 0;
+        while (true)
         {
-          UNUSED(i);
-          break;
-        }
-        i++;
+          PagemapEntry* value = get_node<create_addr>(e, result);
+          if (unlikely(!result))
+            return {nullptr, 0};
 
-        if (i == INDEX_LEVELS)
-          break;
+          shift -= BITS_PER_INDEX_LEVEL;
+          ix = (static_cast<size_t>(addr) >> shift) & ENTRIES_MASK;
+          e = &value->entries[ix];
+
+          if constexpr (INDEX_LEVELS == 1)
+          {
+            UNUSED(i);
+            break;
+          }
+          else
+          {
+            i++;
+            if (i == INDEX_LEVELS)
+              break;
+          }
+        }
       }
 
       Leaf* leaf = reinterpret_cast<Leaf*>(get_node<create_addr>(e, result));
diff --git a/src/test/func/pagemap/pagemap.cc b/src/test/func/pagemap/pagemap.cc
new file mode 100644
index 0000000..571cff0
--- /dev/null
+++ b/src/test/func/pagemap/pagemap.cc
@@ -0,0 +1,55 @@
+/**
+ * Unit tests for operations in pagemap operations.
+ *
+ * Currently this tests a very specific case where the pagemap
+ * requires multiple levels of index. This was incorrectly implemented,
+ * but no examples were using multiple levels of pagemap.
+ */
+
+#include <ds/bits.h>
+#include <iostream>
+#include <snmalloc.h>
+#include <test/setup.h>
+
+using namespace snmalloc;
+using T = size_t;
+static constexpr size_t GRANULARITY_BITS = 9;
+static constexpr T PRIME = 251;
+Pagemap<GRANULARITY_BITS, T, 0> pagemap_test;
+
+int main(int argc, char** argv)
+{
+  UNUSED(argc);
+  UNUSED(argv);
+
+  setup();
+
+  T value = 0;
+  for (uintptr_t ptr = 0; ptr < bits::one_at_bit(36);
+       ptr += bits::one_at_bit(GRANULARITY_BITS + 3))
+  {
+    pagemap_test.set(ptr, value);
+    value++;
+    if (value == PRIME)
+      value = 0;
+    if ((ptr % (1ULL << 32)) == 0)
+      std::cout << "." << std::flush;
+  }
+
+  std::cout << std::endl;
+  value = 0;
+  for (uintptr_t ptr = 0; ptr < bits::one_at_bit(36);
+       ptr += bits::one_at_bit(GRANULARITY_BITS + 3))
+  {
+    T result = pagemap_test.get(ptr);
+    if (value != result)
+      Pal::error("Pagemap corrupt!");
+    value++;
+    if (value == PRIME)
+      value = 0;
+
+    if ((ptr % (1ULL << 32)) == 0)
+      std::cout << "." << std::flush;
+  }
+  std::cout << std::endl;
+}