diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 87be5afb5e..8cac2f788e 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -7115,7 +7115,7 @@ virDomainDefValidateInternal(const virDomainDef *def,
  */
 int
 virDomainDefValidate(virDomainDefPtr def,
-                     virCapsPtr caps,
+                     virCapsPtr caps G_GNUC_UNUSED,
                      unsigned int parseFlags,
                      virDomainXMLOptionPtr xmlopt)
 {
@@ -7130,7 +7130,7 @@ virDomainDefValidate(virDomainDefPtr def,
 
     /* call the domain config callback */
     if (xmlopt->config.domainValidateCallback &&
-        xmlopt->config.domainValidateCallback(def, caps, xmlopt->config.priv) < 0)
+        xmlopt->config.domainValidateCallback(def, xmlopt->config.priv) < 0)
         return -1;
 
     /* iterate the devices */
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 844340e67c..c8f8d0869f 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2671,7 +2671,6 @@ typedef void (*virDomainDefPostParseDataFree)(void *parseOpaque);
  * for configurations that were previously accepted. This shall not modify the
  * config. */
 typedef int (*virDomainDefValidateCallback)(const virDomainDef *def,
-                                            virCapsPtr caps,
                                             void *opaque);
 
 /* Called once per device, for adjusting per-device settings while
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 24aae6fb82..8ce7bda866 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -4972,7 +4972,6 @@ qemuDomainValidateCpuCount(const virDomainDef *def,
 
 static int
 qemuDomainDefValidate(const virDomainDef *def,
-                      virCapsPtr caps G_GNUC_UNUSED,
                       void *opaque)
 {
     virQEMUDriverPtr driver = opaque;
diff --git a/src/vz/vz_driver.c b/src/vz/vz_driver.c
index 78aa85825a..35baab1b82 100644
--- a/src/vz/vz_driver.c
+++ b/src/vz/vz_driver.c
@@ -259,7 +259,6 @@ vzDomainDefPostParse(virDomainDefPtr def,
 
 static int
 vzDomainDefValidate(const virDomainDef *def,
-                    virCapsPtr caps G_GNUC_UNUSED,
                     void *opaque)
 {
     if (vzCheckUnsupportedControllers(def, opaque) < 0)