qemu: command: Align memory sizes only on fresh starts

When we are starting a qemu process for an incomming migration or
snapshot reloading we should not modify the memory sizes in the domain
since we could potentially change the guest ABI that was tediously
checked before. Additionally the function now updates the initial memory
size according to the NUMA node size, which should not happen if we are
restoring state.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1252685

src/qemu/qemu_command.c

@@ -9318,7 +9318,8 @@ qemuBuildCommandLine(virConnectPtr conn,
     if (qemuBuildDomainLoaderCommandLine(cmd, def, qemuCaps) < 0)
         goto error;
 
-    if (qemuDomainAlignMemorySizes(def) < 0)
+    if (!migrateFrom && !snapshot &&
+        qemuDomainAlignMemorySizes(def) < 0)
         goto error;
 
     virCommandAddArg(cmd, "-m");

tests/qemuxml2argvdata/qemuxml2argv-restore-v1.args

@@ -1,5 +1,5 @@
 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
 /usr/bin/qemu -S -M \
-pc -m 214 -smp 1 -nographic -monitor unix:/tmp/test-monitor,server,nowait \
+pc -m 213 -smp 1 -nographic -monitor unix:/tmp/test-monitor,server,nowait \
 -no-acpi -boot c -usb -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel \
 none -incoming stdio