diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f775170e32..3236196c14 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -1900,8 +1900,7 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
     if (disk->cachemode != VIR_DOMAIN_DISK_CACHE_DEFAULT) {
         /* VIR_DOMAIN_DISK_DEVICE_LUN translates into 'scsi-block'
          * where any caching setting makes no sense. */
-        if (disk->device != VIR_DOMAIN_DISK_DEVICE_LUN &&
-            virQEMUCapsGet(qemuCaps, QEMU_CAPS_DISK_WRITE_CACHE)) {
+        if (disk->device != VIR_DOMAIN_DISK_DEVICE_LUN) {
             bool wb;
 
             if (qemuDomainDiskCachemodeFlags(disk->cachemode, &wb, NULL,
diff --git a/tests/qemuxml2argvdata/controller-order.args b/tests/qemuxml2argvdata/controller-order.args
index c0ba064bec..242639591c 100644
--- a/tests/qemuxml2argvdata/controller-order.args
+++ b/tests/qemuxml2argvdata/controller-order.args
@@ -29,7 +29,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-fdr/.config \
 -device usb-ccid,id=ccid0,bus=usb.0,port=1.1 \
 -blockdev '{"driver":"file","filename":"/tmp/fdr.img","aio":"native","node-name":"libvirt-2-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-2-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"raw","file":"libvirt-2-storage"}' \
--device virtio-blk-pci,bus=pci.0,addr=0x5,share-rw=on,drive=libvirt-2-format,id=virtio-disk0,bootindex=1 \
+-device virtio-blk-pci,bus=pci.0,addr=0x5,share-rw=on,drive=libvirt-2-format,id=virtio-disk0,bootindex=1,write-cache=on \
 -blockdev '{"driver":"file","filename":"/tmp/Fedora-17-x86_64-Live-Desktop.iso","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":true,"driver":"raw","file":"libvirt-1-storage"}' \
 -device ide-cd,bus=ide.1,unit=0,drive=libvirt-1-format,id=ide0-1-0 \
diff --git a/tests/qemuxml2argvdata/video-device-pciaddr-default.args b/tests/qemuxml2argvdata/video-device-pciaddr-default.args
index e216aacc64..9b421c012d 100644
--- a/tests/qemuxml2argvdata/video-device-pciaddr-default.args
+++ b/tests/qemuxml2argvdata/video-device-pciaddr-default.args
@@ -27,7 +27,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -vnc 127.0.0.1:0,audiodev=audio1 \
 -device qxl-vga,id=video0,max_outputs=1,ram_size=67108864,vram_size=67108864,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-qxl-device-vgamem.args b/tests/qemuxml2argvdata/video-qxl-device-vgamem.args
index 1332f798da..14b3931140 100644
--- a/tests/qemuxml2argvdata/video-qxl-device-vgamem.args
+++ b/tests/qemuxml2argvdata/video-qxl-device-vgamem.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device qxl-vga,id=video0,max_outputs=1,ram_size=67108864,vram_size=67108864,vgamem_mb=16,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-qxl-device.args b/tests/qemuxml2argvdata/video-qxl-device.args
index dc679b7aa5..570bb64323 100644
--- a/tests/qemuxml2argvdata/video-qxl-device.args
+++ b/tests/qemuxml2argvdata/video-qxl-device.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device qxl-vga,id=video0,max_outputs=1,ram_size=67108864,vram_size=67108864,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-qxl-sec-device-vgamem.args b/tests/qemuxml2argvdata/video-qxl-sec-device-vgamem.args
index 42de87528c..1715ee0cf7 100644
--- a/tests/qemuxml2argvdata/video-qxl-sec-device-vgamem.args
+++ b/tests/qemuxml2argvdata/video-qxl-sec-device-vgamem.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device qxl-vga,id=video0,max_outputs=1,ram_size=67108864,vram_size=67108864,vgamem_mb=16,bus=pci.0,addr=0x2 \
 -device qxl,id=video1,max_outputs=1,ram_size=67108864,vram_size=67108864,vgamem_mb=16,bus=pci.0,addr=0x4 \
diff --git a/tests/qemuxml2argvdata/video-qxl-sec-device.args b/tests/qemuxml2argvdata/video-qxl-sec-device.args
index c55e3eb9db..6140fffa72 100644
--- a/tests/qemuxml2argvdata/video-qxl-sec-device.args
+++ b/tests/qemuxml2argvdata/video-qxl-sec-device.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device qxl-vga,id=video0,max_outputs=1,ram_size=67108864,vram_size=67108864,bus=pci.0,addr=0x2 \
 -device qxl,id=video1,max_outputs=1,ram_size=67108864,vram_size=67108864,bus=pci.0,addr=0x4 \
diff --git a/tests/qemuxml2argvdata/video-vga-device-vgamem.args b/tests/qemuxml2argvdata/video-vga-device-vgamem.args
index 8d1108216e..c9ac626b77 100644
--- a/tests/qemuxml2argvdata/video-vga-device-vgamem.args
+++ b/tests/qemuxml2argvdata/video-vga-device-vgamem.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device VGA,id=video0,vgamem_mb=16,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-vga-device.args b/tests/qemuxml2argvdata/video-vga-device.args
index 1a832df4cb..10f3b38e09 100644
--- a/tests/qemuxml2argvdata/video-vga-device.args
+++ b/tests/qemuxml2argvdata/video-vga-device.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device VGA,id=video0,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-virtio-gpu-device.args b/tests/qemuxml2argvdata/video-virtio-gpu-device.args
index 1dd818f5fc..2c31631572 100644
--- a/tests/qemuxml2argvdata/video-virtio-gpu-device.args
+++ b/tests/qemuxml2argvdata/video-virtio-gpu-device.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device virtio-gpu-pci,id=video0,max_outputs=1,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-virtio-gpu-sdl-gl.args b/tests/qemuxml2argvdata/video-virtio-gpu-sdl-gl.args
index d4ab9fac16..adeab6d53d 100644
--- a/tests/qemuxml2argvdata/video-virtio-gpu-sdl-gl.args
+++ b/tests/qemuxml2argvdata/video-virtio-gpu-sdl-gl.args
@@ -27,7 +27,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -display sdl,gl=on \
 -device virtio-gpu-pci,id=video0,virgl=on,max_outputs=1,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-virtio-gpu-spice-gl.args b/tests/qemuxml2argvdata/video-virtio-gpu-spice-gl.args
index f198d4da8b..60862a48d7 100644
--- a/tests/qemuxml2argvdata/video-virtio-gpu-spice-gl.args
+++ b/tests/qemuxml2argvdata/video-virtio-gpu-spice-gl.args
@@ -27,7 +27,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"spice"}' \
 -spice port=0,gl=on,rendernode=/dev/dri/foo,seamless-migration=on \
 -device virtio-gpu-pci,id=video0,virgl=on,max_outputs=1,bus=pci.0,addr=0x2 \
diff --git a/tests/qemuxml2argvdata/video-virtio-gpu-virgl.args b/tests/qemuxml2argvdata/video-virtio-gpu-virgl.args
index 140bee6187..87c79a4865 100644
--- a/tests/qemuxml2argvdata/video-virtio-gpu-virgl.args
+++ b/tests/qemuxml2argvdata/video-virtio-gpu-virgl.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device virtio-gpu-pci,id=video0,virgl=on,max_outputs=1,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
diff --git a/tests/qemuxml2argvdata/video-virtio-vga.args b/tests/qemuxml2argvdata/video-virtio-vga.args
index 704a6334b0..f0352d7583 100644
--- a/tests/qemuxml2argvdata/video-virtio-vga.args
+++ b/tests/qemuxml2argvdata/video-virtio-vga.args
@@ -28,7 +28,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
 -usb \
 -blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/QEMUGuest1","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"}' \
 -blockdev '{"node-name":"libvirt-1-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-1-storage"}' \
--device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1,write-cache=on \
 -audiodev '{"id":"audio1","driver":"none"}' \
 -device virtio-vga,id=video0,max_outputs=1,bus=pci.0,addr=0x2 \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \