[libvirt] [PATCH] qemu: Improve error if setmem fails for lacking of balloon support

[Osier Yang]

"cannot set memory of an active domain" is misleading, it sounds
like setting memory of active domain is not supported.
---
 src/qemu/qemu_driver.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 5713650..bb33fd5 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -2037,7 +2037,8 @@ static int qemudDomainSetMemoryFlags(virDomainPtr dom, unsigned long newmem,
             /* Lack of balloon support is a fatal error */
             if (r == 0) {
                 qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
-                                _("cannot set memory of an active domain"));
+                                _("Lacks of balloon support, perhaps"
+                                  " the balloon device is disabled"));
                 goto endjob;
             }
         }
-- 
1.7.7.3