diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 9f40276d6405ee01c942f4aecc56cec9497369c6..7d92f3a54478bbfa93899a14c11bd6f305a92c30 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -3362,8 +3362,13 @@ qemuDomainAgentAvailable(virDomainObjPtr vm,
 
 
 static unsigned long long
-qemuDomainGetMemorySizeAlignment(virDomainDefPtr def ATTRIBUTE_UNUSED)
+qemuDomainGetMemorySizeAlignment(virDomainDefPtr def)
 {
+    /* PPC requires the memory sizes to be rounded to 256MiB increments, so
+     * round them to the size always. */
+    if (ARCH_IS_PPC64(def->os.arch))
+        return 256 * 1024;
+
     /* Align memory size. QEMU requires rounding to next 4KiB block.
      * We'll take the "traditional" path and round it to 1MiB*/
 
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-pseries-cpu-compat.args b/tests/qemuxml2argvdata/qemuxml2argv-pseries-cpu-compat.args
index 64df406e1d4ca1b7dcc360511527a04254314af4..305e92438182f9edbe1a87325a7f4fee28b8dd0f 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-pseries-cpu-compat.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-pseries-cpu-compat.args
@@ -1,7 +1,7 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test \
 QEMU_AUDIO_DRV=none /usr/bin/qemu-system-ppc64 -S -M pseries \
 -cpu host,compat=power7 \
--m 214 -smp 4 -nographic -nodefconfig -nodefaults \
+-m 256 -smp 4 -nographic -nodefconfig -nodefaults \
 -chardev socket,id=charmonitor,path=/tmp/test-monitor,server,nowait \
 -mon chardev=charmonitor,id=monitor,mode=readline -no-acpi -boot c -usb \
 -chardev pty,id=charserial0 \