diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 9e0b1785d8..0c343b648c 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -4650,7 +4650,7 @@ qemuBuildMemoryBackendStr(unsigned long long size,
         virBufferAsprintf(&buf, "memory-backend-ram,id=%s%zu", aliasPrefix, id);
     }
 
-    virBufferAsprintf(&buf, ",size=%lluM", size / 1024);
+    virBufferAsprintf(&buf, ",size=%llu", size * 1024);
 
     if (userNodeset) {
         if (!(nodemask = virBitmapFormat(userNodeset)))
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
index b954fbc7d2..46ec751821 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
@@ -1,16 +1,20 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 4096 -smp 4 \
 -object memory-backend-file,id=ram-node0,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1024M,host-nodes=0-3,policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
+policy=bind \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
 -object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=1024M,host-nodes=0-3,policy=bind \
+mem-path=/dev/hugepages2M/libvirt/qemu,size=1073741824,host-nodes=0-3,\
+policy=bind \
 -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
 -object memory-backend-file,id=ram-node2,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1024M,host-nodes=0-3,policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
+policy=bind \
 -numa node,nodeid=2,cpus=2,memdev=ram-node2 \
 -object memory-backend-file,id=ram-node3,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1024M,host-nodes=3,policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=3,\
+policy=bind \
 -numa node,nodeid=3,cpus=3,memdev=ram-node3 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel none
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
index 90ab776398..0488800b2c 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
@@ -1,10 +1,10 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 1024 -smp 2 \
 -object memory-backend-file,id=ram-node0,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=256M \
+mem-path=/dev/hugepages2M/libvirt/qemu,size=268435456 \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
 -object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=768M \
+mem-path=/dev/hugepages2M/libvirt/qemu,size=805306368 \
 -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c \
 -usb -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel none
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
index b93252004e..3bca26ce56 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
@@ -2,7 +2,7 @@ LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 1024 -smp 2 \
 -numa node,nodeid=0,cpus=0,mem=256 \
 -object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=768M \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=805306368 \
 -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel none
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
index 27f476f0da..a6e4d95fe0 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
@@ -1,18 +1,20 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M pc -m 4096 -smp 4 \
 -object memory-backend-file,id=ram-node0,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1024M,host-nodes=0-3,policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
+policy=bind \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
 -object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,share=yes,size=1024M,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages2M/libvirt/qemu,share=yes,size=1073741824,\
+host-nodes=0-3,policy=bind \
 -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
 -object memory-backend-file,id=ram-node2,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,share=no,size=1024M,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,share=no,size=1073741824,\
+host-nodes=0-3,policy=bind \
 -numa node,nodeid=2,cpus=2,memdev=ram-node2 \
 -object memory-backend-file,id=ram-node3,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1024M,host-nodes=3,policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=3,\
+policy=bind \
 -numa node,nodeid=3,cpus=3,memdev=ram-node3 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -usb \
 -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel none
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode-no-memory.args b/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode-no-memory.args
index 4f1f2aa10a..f0e35b744f 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode-no-memory.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode-no-memory.args
@@ -1,6 +1,7 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/kvm -S -M pc -m 64 -smp 2 \
--object memory-backend-ram,id=ram-node0,size=32M,host-nodes=3,policy=preferred \
+-object memory-backend-ram,id=ram-node0,size=33554432,host-nodes=3,\
+policy=preferred \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
 -numa node,nodeid=1,cpus=1,mem=32 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode.args b/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode.args
index 18007d59a2..513d657646 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode.args
@@ -1,10 +1,12 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/kvm -S -M pc -m 24104 -smp 32 \
--object memory-backend-ram,id=ram-node0,size=20M,host-nodes=3,policy=preferred \
+-object memory-backend-ram,id=ram-node0,size=20971520,host-nodes=3,\
+policy=preferred \
 -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
--object memory-backend-ram,id=ram-node1,size=645M,host-nodes=0-7,policy=bind \
+-object memory-backend-ram,id=ram-node1,size=676331520,host-nodes=0-7,\
+policy=bind \
 -numa node,nodeid=1,cpus=1-27,cpus=29,memdev=ram-node1 \
--object memory-backend-ram,id=ram-node2,size=23440M,\
+-object memory-backend-ram,id=ram-node2,size=24578621440,\
 host-nodes=1-2,host-nodes=5,host-nodes=7,policy=bind \
 -numa node,nodeid=2,cpus=28,cpus=30-31,memdev=ram-node2 \
 -nographic -monitor unix:/tmp/test-monitor,server,nowait \