From 95e2415b95fdf9619b0444b053e84b5a6e4e7b20 Mon Sep 17 00:00:00 2001
From: Jiri Denemark <jdenemar@redhat.com>
Date: Tue, 10 Nov 2015 12:41:01 +0100
Subject: [PATCH] qemu: Kill QEMU process if Prepare phase fails

Some failure paths in qemuMigrationPrepareAny forgot to kill the just
started QEMU process. This patch fixes this by combining 'stop' and
'endjob' label into a new label 'stopjob'. This name was chosen to avoid
confusion with the most common semantics of 'endjob'. Normally, 'endjob'
is always called at the end of an API to stop the job we entered at the
beginning. In qemuMigrationPrepareAny we only want to stop the job in
failure path; on success we need to carry the job over to the Finish
phase.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/qemu/qemu_migration.c | 31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 4ab6ab738..9a4f19fda 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -3522,7 +3522,7 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
         (pipe(dataFD) < 0 || virSetCloseExec(dataFD[1]) < 0)) {
         virReportSystemError(errno, "%s",
                              _("cannot create pipe for tunnelled migration"));
-        goto endjob;
+        goto stopjob;
     }
 
     virObjectUnref(priv->qemuCaps);
@@ -3530,11 +3530,11 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                                                 vm->def->emulator,
                                                 vm->def->os.machine);
     if (!priv->qemuCaps)
-        goto endjob;
+        goto stopjob;
 
     if (!(migrateFrom = qemuMigrationPrepareIncoming(vm, tunnel, protocol,
                                                      listenAddress, port)))
-        goto endjob;
+        goto stopjob;
 
     /* Start the QEMU daemon, with the same command-line arguments plus
      * -incoming $migrateFrom
@@ -3545,14 +3545,14 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                          VIR_QEMU_PROCESS_START_PAUSED |
                          VIR_QEMU_PROCESS_START_AUTODESTROY) < 0) {
         virDomainAuditStart(vm, "migrated", false);
-        goto endjob;
+        goto stopjob;
     }
 
     if (tunnel) {
         if (virFDStreamOpen(st, dataFD[1]) < 0) {
             virReportSystemError(errno, "%s",
                                  _("cannot pass pipe for tunnelled migration"));
-            goto stop;
+            goto stopjob;
         }
         dataFD[1] = -1; /* 'st' owns the FD now & will close it */
     }
@@ -3560,17 +3560,17 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
     if (qemuMigrationSetCompression(driver, vm,
                                     flags & VIR_MIGRATE_COMPRESSED,
                                     QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
-        goto stop;
+        goto stopjob;
 
     if (STREQ_NULLABLE(protocol, "rdma") &&
         virProcessSetMaxMemLock(vm->pid, vm->def->mem.hard_limit << 10) < 0) {
-        goto stop;
+        goto stopjob;
     }
 
     if (qemuMigrationSetPinAll(driver, vm,
                                flags & VIR_MIGRATE_RDMA_PIN_ALL,
                                QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
-        goto stop;
+        goto stopjob;
 
     if (mig->lockState) {
         VIR_DEBUG("Received lockstate %s", mig->lockState);
@@ -3593,7 +3593,7 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
         if (qemuMigrationStartNBDServer(driver, vm, listenAddress,
                                         nmigrate_disks, migrate_disks) < 0) {
             /* error already reported */
-            goto endjob;
+            goto stopjob;
         }
         cookieFlags |= QEMU_MIGRATION_COOKIE_NBD;
     }
@@ -3608,7 +3608,7 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
     }
 
     if (qemuDomainCleanupAdd(vm, qemuMigrationPrepareCleanup) < 0)
-        goto endjob;
+        goto stopjob;
 
     if (!(flags & VIR_MIGRATE_OFFLINE)) {
         virDomainAuditStart(vm, "migrated", true);
@@ -3647,12 +3647,13 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
     virNWFilterUnlockFilterUpdates();
     return ret;
 
- stop:
-    virDomainAuditStart(vm, "migrated", false);
-    qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FAILED,
-                    VIR_QEMU_PROCESS_STOP_MIGRATED);
+ stopjob:
+    if (vm->def->id != -1) {
+        virDomainAuditStart(vm, "migrated", false);
+        qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FAILED,
+                        VIR_QEMU_PROCESS_STOP_MIGRATED);
+    }
 
- endjob:
     qemuMigrationJobFinish(driver, vm);
     goto cleanup;
 }
-- 
2.39.5