1 files changed, 21 insertions, 0 deletions
diff --git a/OvmfPkg/VirtioGpuDxe/Commands.c b/OvmfPkg/VirtioGpuDxe/Commands.c
index 595a3717d9..db5bdbca4b 100644
--- a/OvmfPkg/VirtioGpuDxe/Commands.c
+++ b/OvmfPkg/VirtioGpuDxe/Commands.c
@@ -355,6 +355,27 @@ VirtioGpuExitBoot (
 
   VgpuDev = Context;
   VgpuDev->VirtIo->SetDeviceStatus (VgpuDev->VirtIo, 0);
+
+  //
+  // If VirtioGpuDriverBindingStart() and VirtioGpuDriverBindingStop() have
+  // been called thus far in such a sequence that right now our (sole) child
+  // handle exists -- with the GOP on it standing for head (scanout) #0 --,
+  // then we have to unmap the current video mode's backing store.
+  //
+  if (VgpuDev->Child != NULL) {
+    //
+    // The current video mode is guaranteed to have a valid and mapped backing
+    // store, due to the first Gop.SetMode() call, made internally in
+    // InitVgpuGop().
+    //
+    ASSERT (VgpuDev->Child->BackingStore != NULL);
+
+    VgpuDev->VirtIo->UnmapSharedBuffer (
+                       VgpuDev->VirtIo,
+                       VgpuDev->Child->BackingStoreMap
+                       );
+  }
+
   VgpuDev->VirtIo->UnmapSharedBuffer (VgpuDev->VirtIo, VgpuDev->RingMap);
 }