diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c index 4e2a27a3d6..8eb3046244 100644 --- a/hw/display/xenfb.c +++ b/hw/display/xenfb.c @@ -789,8 +789,9 @@ static void xenfb_handle_events(struct XenFB *xenfb) prod = page->out_prod; out_cons = page->out_cons; - if (prod == out_cons) - return; + if (prod - out_cons >= XENFB_OUT_RING_LEN) { + return; + } xen_rmb(); /* ensure we see ring contents up to prod */ for (cons = out_cons; cons != prod; cons++) { union xenfb_out_event *event = &XENFB_OUT_RING_REF(page, cons);