3 files changed, 12 insertions, 1 deletions
diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c b/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
index 5594e6699..cc6e77e38 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
@@ -573,6 +573,12 @@ EhcCheckUrbResult (
 
   ASSERT ((Ehc != NULL) && (Urb != NULL) && (Urb->Qh != NULL));
 
+  // The URB is already being processed, we do not want the callback to be
+  // called twice for the same URB
+  if (Urb->InProgress) {
+    return FALSE;
+  }
+
   Finished        = TRUE;
   Urb->Completed  = 0;
 
@@ -992,6 +998,9 @@ EhcMonitorAsyncRequests (
       continue;
     }
 
+    // Mark the URB as 'in-progress' to prevent the URB to be processed twice.
+    Urb->InProgress = TRUE;
+
     //
     // Flush any PCI posted write transactions from a PCI host
     // bridge to system memory.
diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.c b/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.c
index 6afb327df..1ad37d5bd 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.c
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.c
@@ -600,6 +600,7 @@ EhcCreateUrb (
   Urb->DataLen    = DataLen;
   Urb->Callback   = Callback;
   Urb->Context    = Context;
+  Urb->InProgress = FALSE;
 
   PciIo           = Ehc->PciIo;
   Urb->Qh         = EhcCreateQh (Ehc, &Urb->Ep);
diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.h b/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.h
index 02e9af81b..0c80e7624 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.h
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/EhciUrb.h
@@ -232,7 +232,8 @@ struct _URB {
   // Transaction result
   //
   UINT32                          Result;
-  UINTN                           Completed;    // completed data length
+  BOOLEAN                         InProgress;   // defined when the URB is being processed
+  UINTN                           Completed;    // Length of the data being processed
   UINT8                           DataToggle;
 };