diff --git a/lldb/source/Target/Memory.cpp b/lldb/source/Target/Memory.cpp
--- a/lldb/source/Target/Memory.cpp
+++ b/lldb/source/Target/Memory.cpp
@@ -232,8 +232,17 @@
         if (process_bytes_read == 0)
           return dst_len - bytes_left;
 
-        if (process_bytes_read != cache_line_byte_size)
-          data_buffer_heap_up->SetByteSize(process_bytes_read);
+        if (process_bytes_read != cache_line_byte_size) {
+          // If the data available to read is less than an entire page, we don't
+          // resize the buffer because we still want to return at least
+          // 'dst_len' bytes. In that case fill the rest of the buffer with a
+          // fail-fill value (0xdd).
+          if (process_bytes_read >= data_buffer_heap_up->GetByteSize())
+            data_buffer_heap_up->SetByteSize(process_bytes_read);
+          else
+            memset(data_buffer_heap_up->GetBytes() + process_bytes_read, 0xdd,
+                   data_buffer_heap_up->GetByteSize() - process_bytes_read);
+        }
         m_L2_cache[curr_addr] = DataBufferSP(data_buffer_heap_up.release());
         // We have read data and put it into the cache, continue through the
         // loop again to get the data out of the cache...