Add a hint message to loadvm and exits on failure

This patch adds a small hint for the failure case of the load snapshot
process. It may be useful for users to remember that the VM
configuration has changed between the save and load processes.

(qemu) loadvm vm-20180903083641
Unknown savevm section or instance 'cpu_common' 4.
Make sure that your current VM setup matches your saved VM setup, including any hotplugged devices
Error -22 while loading VM state
(qemu) device_add host-spapr-cpu-core,core-id=4
(qemu) loadvm vm-20180903083641
(qemu) c
(qemu) info status
VM status: running

It also exits Qemu if the snapshot cannot be loaded before reaching the
main loop (-loadvm in the command line).

$ qemu-system-ppc64 ... -loadvm vm-20180903083641
qemu-system-ppc64: Unknown savevm section or instance 'cpu_common' 4.
Make sure that your current VM setup matches your saved VM setup, including any hotplugged devices
qemu-system-ppc64: Error -22 while loading VM state
$

Signed-off-by: Jose Ricardo Ziviani <joserz@linux.ibm.com>
Message-Id: <20180903162613.15877-1-joserz@linux.ibm.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

diff --git a/migration/savevm.c b/migration/savevm.c
index 13e51f0e341781c050eae28d769b4dff7f9cf5ad..9692577318737a4b8ffc4c09e62bf869472e7602 100644 (file)
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2078,7 +2078,9 @@ qemu_loadvm_section_start_full(QEMUFile *f, MigrationIncomingState *mis)
     /* Find savevm section */
     se = find_se(idstr, instance_id);
     if (se == NULL) {
-        error_report("Unknown savevm section or instance '%s' %d",
+        error_report("Unknown savevm section or instance '%s' %d. "
+                     "Make sure that your current VM setup matches your "
+                     "saved VM setup, including any hotplugged devices",
                      idstr, instance_id);
         return -EINVAL;
     }

diff --git a/vl.c b/vl.c
index 694bb67890422f885a712480fee6e249fb7ddda6..afbbec2383dd0c6da2460598f3db9b637da092b1 100644 (file)
--- a/vl.c
+++ b/vl.c
@@ -4530,6 +4530,7 @@ int main(int argc, char **argv, char **envp)
         if (load_snapshot(loadvm, &local_err) < 0) {
             error_report_err(local_err);
             autostart = 0;
+            exit(1);
         }
     }