diff --git a/system/dev/usb/xhci/xdc-transfer.cpp b/system/dev/usb/xhci/xdc-transfer.cpp
index c636732..e782949 100644
--- a/system/dev/usb/xhci/xdc-transfer.cpp
+++ b/system/dev/usb/xhci/xdc-transfer.cpp
@@ -54,7 +54,8 @@
 
     // If we get here, then we are ready to ring the doorbell.
     // Save the ring position so we can update the ring dequeue ptr once the transfer completes.
-    req->context = ring->current;
+    xdc_req_internal_t* req_int = USB_REQ_TO_XDC_INTERNAL(req, sizeof(usb_request_t));
+    req_int->context = ring->current;
     xdc_ring_doorbell(xdc, ep);
 
     return ZX_OK;
@@ -287,7 +288,7 @@
     list_delete(&test_int->node);
 
     // Update our copy of the dequeue_ptr to the TRB following this transaction.
-    xhci_set_dequeue_ptr(ring, static_cast<xhci_trb_t*>(req->context));
+    xhci_set_dequeue_ptr(ring, static_cast<xhci_trb_t*>(test_int->context));
     xdc_process_transactions_locked(xdc, ep);
 
     // Save the request to be completed later out of the lock.
diff --git a/system/dev/usb/xhci/xdc.h b/system/dev/usb/xhci/xdc.h
index 20b5d48..f784b0d 100644
--- a/system/dev/usb/xhci/xdc.h
+++ b/system/dev/usb/xhci/xdc.h
@@ -139,6 +139,7 @@
     list_node_t node;
     usb_request_complete_cb complete_cb;
     void* cookie;
+    void* context;
 } xdc_req_internal_t;
 
 #define USB_REQ_TO_XDC_INTERNAL(req, size) \
diff --git a/system/dev/usb/xhci/xhci-transfer.cpp b/system/dev/usb/xhci/xhci-transfer.cpp
index 5b7d647..60a4a7e 100644
--- a/system/dev/usb/xhci/xhci-transfer.cpp
+++ b/system/dev/usb/xhci/xhci-transfer.cpp
@@ -296,9 +296,10 @@
         state->needs_status = false;
     }
 
+    xhci_usb_request_internal_t* req_int = USB_REQ_TO_XHCI_INTERNAL(req);
     // if we get here, then we are ready to ring the doorbell
     // update dequeue_ptr to TRB following this transaction
-    req->context = (void *)ring->current;
+    req_int->context = (void *)ring->current;
 
     XHCI_WRITE32(&xhci->doorbells[header->device_id], ep_index + 1);
     // it seems we need to ring the doorbell a second time when transitioning from STOPPED
@@ -785,7 +786,7 @@
     }
 
     // update dequeue_ptr to TRB following this transaction
-    xhci_set_dequeue_ptr(ring, static_cast<xhci_trb_t*>(req->context));
+    xhci_set_dequeue_ptr(ring, static_cast<xhci_trb_t*>(req_int->context));
 
     // remove request from pending_reqs
     xhci_delete_req_node(xhci, req);
diff --git a/system/dev/usb/xhci/xhci.h b/system/dev/usb/xhci/xhci.h
index 626411e..9b4172a 100644
--- a/system/dev/usb/xhci/xhci.h
+++ b/system/dev/usb/xhci/xhci.h
@@ -88,6 +88,7 @@
      void* cookie;
      // for queueing request at xhci level
      list_node_t node;
+     void* context;
 } xhci_usb_request_internal_t;
 
 #define USB_REQ_TO_XHCI_INTERNAL(req) \
diff --git a/system/ulib/ddk/include/ddk/protocol/usb.h b/system/ulib/ddk/include/ddk/protocol/usb.h
index 1b948c4..1dbc607 100644
--- a/system/ulib/ddk/include/ddk/protocol/usb.h
+++ b/system/ulib/ddk/include/ddk/protocol/usb.h
@@ -98,8 +98,6 @@
 
     usb_response_t response;
 
-    void *context;
-
     // The release_cb() callback is set by the allocator and is
     // invoked by the 'usb_request_release' method when it is called
     // by the requestor.