diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index dcdef7c923..30f0df8713 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -61,6 +61,7 @@ static void ich9_gpe_writeb(void *opaque, hwaddr addr, uint64_t val,
 {
     ICH9LPCPMRegs *pm = opaque;
     acpi_gpe_ioport_writeb(&pm->acpi_regs, addr, val);
+    acpi_update_sci(&pm->acpi_regs, pm->irq);
 }
 
 static const MemoryRegionOps ich9_gpe_ops = {