as suggested by Andreas
Signed-off-by: liguang <lig.f...@cn.fujitsu.com>
---
hw/i386/pc.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index b881314..b0454eb 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -503,6 +503,11 @@ static void port92_realizefn(DeviceState *dev, Error **err)
ISADevice *isadev = ISA_DEVICE(dev);
Port92State *s = PORT92(dev);
+ if (s->a20_out == NULL) {
+ error_setg(err, "Can't create port92 device.\n");
+ return;
+ }
+
memory_region_init_io(&s->io, &port92_ops, s, "port92", 1);
isa_register_ioport(isadev, &s->io, 0x92);
--
1.7.2.5
