Initialize qemuImageBinary path at startup

src/qemu/qemu_conf.h

@@ -177,7 +177,7 @@ struct _virQEMUDriver {
     /* Immutable pointer, self-locking APIs */
     virDomainObjListPtr domains;
 
-    /* Lazy-load on first use. Unsafe. XXX */
+    /* Immutable pointer */
     char *qemuImgBinary;
 
     /* Immutable pointer, lockless APIs. Pointless abstraction */

src/qemu/qemu_domain.c

@@ -1612,14 +1612,9 @@ cleanup:
 const char *
 qemuFindQemuImgBinary(virQEMUDriverPtr driver)
 {
-    if (!driver->qemuImgBinary) {
-        driver->qemuImgBinary = virFindFileInPath("kvm-img");
-        if (!driver->qemuImgBinary)
-            driver->qemuImgBinary = virFindFileInPath("qemu-img");
-        if (!driver->qemuImgBinary)
-            virReportError(VIR_ERR_INTERNAL_ERROR,
-                           "%s", _("unable to find kvm-img or qemu-img"));
-    }
+    if (!driver->qemuImgBinary)
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       "%s", _("unable to find kvm-img or qemu-img"));
 
     return driver->qemuImgBinary;
 }

src/qemu/qemu_driver.c

@@ -738,6 +738,9 @@ qemuStartup(bool privileged,
                  virStrerror(-rc, ebuf, sizeof(ebuf)));
     }
 
+    qemu_driver->qemuImgBinary = virFindFileInPath("kvm-img");
+    if (!qemu_driver->qemuImgBinary)
+        qemu_driver->qemuImgBinary = virFindFileInPath("qemu-img");
 
     if (!(qemu_driver->lockManager =
           virLockManagerPluginNew(cfg->lockManagerName ?