3 files changed, 12 insertions, 2 deletions
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 17c572c..73090e0 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -2241,6 +2241,11 @@ static void ehci_work_bh(void *opaque)
     uint64_t uframes, skipped_uframes;
     int i;
 
+    if (ehci->working) {
+        return;
+    }
+    ehci->working = true;
+
     t_now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     ns_elapsed = t_now - ehci->last_run_ns;
     uframes = ns_elapsed / UFRAME_TIMER_NS;
@@ -2322,6 +2327,8 @@ static void ehci_work_bh(void *opaque)
         }
         timer_mod(ehci->frame_timer, expire_time);
     }
+
+    ehci->working = false;
 }
 
 static void ehci_work_timer(void *opaque)
diff --git a/hw/usb/hcd-ehci.h b/hw/usb/hcd-ehci.h
index 938d8aa..821f1de 100644
--- a/hw/usb/hcd-ehci.h
+++ b/hw/usb/hcd-ehci.h
@@ -297,6 +297,7 @@ struct EHCIState {
      */
     QEMUTimer *frame_timer;
     QEMUBH *async_bh;
+    bool working;
     uint32_t astate;         /* Current state in asynchronous schedule */
     uint32_t pstate;         /* Current state in periodic schedule     */
     USBPort ports[NB_PORTS];
diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index a0c7960..760135c 100644
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -1912,6 +1912,8 @@ static void xhci_kick_epctx(XHCIEPContext *epctx, unsigned int streamid)
         }
         assert(!xfer->running_retry);
         if (xfer->complete) {
+            /* update ring dequeue ptr */
+            xhci_set_ep_state(xhci, epctx, stctx, epctx->state);
             xhci_ep_free_xfer(epctx->retry);
         }
         epctx->retry = NULL;
@@ -1962,6 +1964,8 @@ static void xhci_kick_epctx(XHCIEPContext *epctx, unsigned int streamid)
             xhci_fire_transfer(xhci, xfer, epctx);
         }
         if (xfer->complete) {
+            /* update ring dequeue ptr */
+            xhci_set_ep_state(xhci, epctx, stctx, epctx->state);
             xhci_ep_free_xfer(xfer);
             xfer = NULL;
         }
@@ -1979,8 +1983,6 @@ static void xhci_kick_epctx(XHCIEPContext *epctx, unsigned int streamid)
             break;
         }
     }
-    /* update ring dequeue ptr */
-    xhci_set_ep_state(xhci, epctx, stctx, epctx->state);
     epctx->kick_active--;
 
     ep = xhci_epid_to_usbep(epctx);