diff --git a/default-configs/moxie-softmmu.mak b/default-configs/moxie-softmmu.mak
index 7e228638b3..e00d099994 100644
--- a/default-configs/moxie-softmmu.mak
+++ b/default-configs/moxie-softmmu.mak
@@ -1,5 +1,6 @@
 # Default configuration for moxie-softmmu
 
+CONFIG_ISA_BUS=y
 CONFIG_MC146818RTC=y
 CONFIG_SERIAL=y
 CONFIG_SERIAL_ISA=y
diff --git a/default-configs/pci.mak b/default-configs/pci.mak
index d8d654838c..60dc6510ec 100644
--- a/default-configs/pci.mak
+++ b/default-configs/pci.mak
@@ -1,4 +1,6 @@
 CONFIG_PCI=y
+# For now, CONFIG_IDE_CORE requires ISA, so we enable it here
+CONFIG_ISA_BUS=y
 CONFIG_VIRTIO_PCI=y
 CONFIG_VIRTIO=y
 CONFIG_USB_UHCI=y
diff --git a/default-configs/sparc-softmmu.mak b/default-configs/sparc-softmmu.mak
index ab796b3d4f..004b0f4e77 100644
--- a/default-configs/sparc-softmmu.mak
+++ b/default-configs/sparc-softmmu.mak
@@ -1,5 +1,6 @@
 # Default configuration for sparc-softmmu
 
+CONFIG_ISA_BUS=y
 CONFIG_ECC=y
 CONFIG_ESP=y
 CONFIG_ESCC=y
diff --git a/default-configs/unicore32-softmmu.mak b/default-configs/unicore32-softmmu.mak
index de38577a35..5f6c4a8047 100644
--- a/default-configs/unicore32-softmmu.mak
+++ b/default-configs/unicore32-softmmu.mak
@@ -1,4 +1,5 @@
 # Default configuration for unicore32-softmmu
+CONFIG_ISA_BUS=y
 CONFIG_PUV3=y
 CONFIG_PTIMER=y
 CONFIG_PCKBD=y
diff --git a/hw/isa/Makefile.objs b/hw/isa/Makefile.objs
index 9164556a4d..fb37c55cf2 100644
--- a/hw/isa/Makefile.objs
+++ b/hw/isa/Makefile.objs
@@ -1,4 +1,4 @@
-common-obj-y += isa-bus.o
+common-obj-$(CONFIG_ISA_BUS) += isa-bus.o
 common-obj-$(CONFIG_APM) += apm.o
 common-obj-$(CONFIG_I82378) += i82378.o
 common-obj-$(CONFIG_PC87312) += pc87312.o