diff --git a/src/dawn_native/Buffer.cpp b/src/dawn_native/Buffer.cpp
index 9ec821e040..3b2b750ffc 100644
--- a/src/dawn_native/Buffer.cpp
+++ b/src/dawn_native/Buffer.cpp
@@ -492,10 +492,7 @@ namespace dawn_native {
                 // even if it did not have a mappable usage.
                 return {};
             case BufferState::Unmapped:
-                if ((mUsage & (wgpu::BufferUsage::MapRead | wgpu::BufferUsage::MapWrite)) == 0) {
-                    return DAWN_VALIDATION_ERROR("Buffer does not have map usage");
-                }
-                return {};
+                return DAWN_VALIDATION_ERROR("Buffer is unmapped");
             case BufferState::Destroyed:
                 return DAWN_VALIDATION_ERROR("Buffer is destroyed");
         }
diff --git a/src/tests/unittests/validation/BufferValidationTests.cpp b/src/tests/unittests/validation/BufferValidationTests.cpp
index 1c93b07ad9..d0179d699e 100644
--- a/src/tests/unittests/validation/BufferValidationTests.cpp
+++ b/src/tests/unittests/validation/BufferValidationTests.cpp
@@ -604,21 +604,21 @@ TEST_F(BufferValidationTest, UnmapWithoutMapUsage) {
 TEST_F(BufferValidationTest, UnmapUnmappedBuffer) {
     {
         wgpu::Buffer buf = CreateMapReadBuffer(4);
-        // Buffer starts unmapped. Unmap should succeed.
-        buf.Unmap();
+        // Buffer starts unmapped. Unmap should fail.
+        ASSERT_DEVICE_ERROR(buf.Unmap());
         buf.MapAsync(wgpu::MapMode::Read, 0, 4, nullptr, nullptr);
         buf.Unmap();
-        // Unmapping twice should succeed
-        buf.Unmap();
+        // Unmapping a second time should fail.
+        ASSERT_DEVICE_ERROR(buf.Unmap());
     }
     {
         wgpu::Buffer buf = CreateMapWriteBuffer(4);
-        // Buffer starts unmapped. Unmap should succeed.
-        buf.Unmap();
+        // Buffer starts unmapped. Unmap should fail.
+        ASSERT_DEVICE_ERROR(buf.Unmap());
         buf.MapAsync(wgpu::MapMode::Write, 0, 4, nullptr, nullptr);
-        // Unmapping twice should succeed
-        buf.Unmap();
         buf.Unmap();
+        // Unmapping a second time should fail.
+        ASSERT_DEVICE_ERROR(buf.Unmap());
     }
 }