diff --git a/src/svm.rs b/src/svm.rs
index b1f2fc6..56eb568 100644
--- a/src/svm.rs
+++ b/src/svm.rs
@@ -315,7 +315,7 @@ impl<'a, T> SvmVec<'a, T> {
     ///
     /// # Safety
     /// May fail to grow buf if memory is not available for new_len.
-    pub fn set_len(&mut self, new_len: usize) -> Result<()> {
+    pub unsafe fn set_len(&mut self, new_len: usize) -> Result<()> {
         if self.cap() < new_len {
             self.buf.grow(new_len)?;
         }
diff --git a/tests/integration_test.rs b/tests/integration_test.rs
index 1559057..73cca9b 100644
--- a/tests/integration_test.rs
+++ b/tests/integration_test.rs
@@ -281,11 +281,11 @@ fn test_opencl_svm_example() -> Result<()> {
             println!("kernel execution duration (ns): {}", duration);
         } else {
             // !is_fine_grained_svm
-            // unsafe { ones.set_len(ARRAY_SIZE) };
-            // unsafe { sums.set_len(ARRAY_SIZE) };
 
-            // Map the input SVM vectors, before setting their data
+            // Resize and map the input SVM vectors, before setting their data
             unsafe {
+                ones.set_len(ARRAY_SIZE)?;
+                sums.set_len(ARRAY_SIZE)? ;
                 queue.enqueue_svm_map(CL_BLOCKING, CL_MAP_WRITE, &mut ones, &[])?;
                 queue.enqueue_svm_map(CL_BLOCKING, CL_MAP_WRITE, &mut sums, &[])?;
             }