lapic error interrupt shows up on real hardware for some reason

ca4d29b1 · Nickolai Zeldovich · 032d2147 · ca4d29b1
--- a/kernel/trap.cc
+++ b/kernel/trap.cc
@@ -95,6 +95,11 @@ trap(struct trapframe *tf)
    cprintf("cpu%d: spurious interrupt at %x:%lx\n",
            mycpu()->id, tf->cs, tf->rip);
    lapiceoi();
+    break;
+  case T_IRQ0 + IRQ_ERROR:
+    cprintf("cpu%d: lapic error?\n", mycpu()->id);
+    lapiceoi();
+    break;
  case T_TLBFLUSH: {
    u64 nreq = tlbflush_req.load();
    lapiceoi();