Hi

That works with the following change:

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 768cef1..1b20a7f 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -2510,6 +2510,7 @@ struct virQEMUCapsCommandLineProps {
 
 static struct virQEMUCapsCommandLineProps virQEMUCapsCommandLine[] = {
     { "machine", "mem-merge", QEMU_CAPS_MEM_MERGE },
+    { "machine", "vmport", QEMU_CAPS_MACHINE_VMPORT_OPT },
     { "drive", "discard", QEMU_CAPS_DRIVE_DISCARD },
     { "realtime", "mlock", QEMU_CAPS_MLOCK },
     { "boot-opts", "strict", QEMU_CAPS_BOOT_STRICT },
@@ -3243,10 +3244,6 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps,
     if (qemuCaps->version >= 1003000)
         virQEMUCapsSet(qemuCaps, QEMU_CAPS_MACHINE_USB_OPT);
 
-    /* vmport option is supported v2.2.0 onwards */
-    if (qemuCaps->version >= 2002000)
-        virQEMUCapsSet(qemuCaps, QEMU_CAPS_MACHINE_VMPORT_OPT);

I can resend this patch if necessary.

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