Accepting request 748738 from home:jfehlig:branches:Virtualization

- libxl: Fix lock manager lock ordering
  2552752f-libxl-fix-lock-manager-lock-ordering.patch
  bsc#1145774

OBS-URL: https://build.opensuse.org/request/show/748738
OBS-URL: https://build.opensuse.org/package/show/Virtualization/libvirt?expand=0&rev=783

2552752f-libxl-fix-lock-manager-lock-ordering.patch

@@ -0,0 +1,87 @@
+commit 2552752f0b6504a80f6306e5aae2c7063d24f1ab
+Author: Jim Fehlig <jfehlig@suse.com>
+Date:   Mon Oct 14 14:01:00 2019 -0600
+
+    libxl: Fix lock manager lock ordering
+    
+    The ordering of lock manager locks in the libxl driver has a flaw that was
+    uncovered by a migration error path. In the perform phase of migration, the
+    source host calls virDomainLockProcessPause to release the lock before
+    sending the VM to the destination host. If the send fails an attempt is made
+    to reacquire the lock with virDomainLockProcessResume, but that too can fail
+    if the destination host has not finished cleaning up the failed VM and
+    releasing the lock it acquired when starting to receive the VM.
+    
+    This change delays calling virDomainLockProcessResume in libxlDomainStart
+    until the VM is successfully created, but before it is unpaused. A similar
+    approach is used by the qemu driver, avoiding the need to release the lock
+    if VM creation fails. In the migration perform phase, releasing the lock
+    with virDomainLockProcessPause is delayed until the VM is successfully
+    sent to the destination, which avoids reacquiring the lock if the send
+    fails.
+    
+    Signed-off-by: Jim Fehlig <jfehlig@suse.com>
+    Reviewed-by: Cole Robinson <crobinso@redhat.com>
+
+Index: libvirt-5.9.0/src/libxl/libxl_domain.c
+===================================================================
+--- libvirt-5.9.0.orig/src/libxl/libxl_domain.c
++++ libvirt-5.9.0/src/libxl/libxl_domain.c
+@@ -1347,13 +1347,6 @@ libxlDomainStart(libxlDriverPrivatePtr d
+                                   NULL) < 0)
+         goto cleanup;
+ 
+-    if (virDomainLockProcessResume(driver->lockManager,
+-                                  "xen:///system",
+-                                  vm,
+-                                  priv->lockState) < 0)
+-        goto cleanup;
+-    VIR_FREE(priv->lockState);
+-
+     if (libxlNetworkPrepareDevices(vm->def) < 0)
+         goto cleanup_dom;
+ 
+@@ -1436,6 +1429,13 @@ libxlDomainStart(libxlDriverPrivatePtr d
+ 
+     libxlLoggerOpenFile(cfg->logger, domid, vm->def->name, config_json);
+ 
++    if (virDomainLockProcessResume(driver->lockManager,
++                                  "xen:///system",
++                                  vm,
++                                  priv->lockState) < 0)
++        goto destroy_dom;
++    VIR_FREE(priv->lockState);
++
+     /* Always enable domain death events */
+     if (libxl_evenable_domain_death(cfg->ctx, vm->def->id, 0, &priv->deathW))
+         goto destroy_dom;
+Index: libvirt-5.9.0/src/libxl/libxl_migration.c
+===================================================================
+--- libvirt-5.9.0.orig/src/libxl/libxl_migration.c
++++ libvirt-5.9.0/src/libxl/libxl_migration.c
+@@ -1240,20 +1240,16 @@ libxlDomainMigrationSrcPerform(libxlDriv
+     sockfd = virNetSocketDupFD(sock, true);
+     virObjectUnref(sock);
+ 
+-    if (virDomainLockProcessPause(driver->lockManager, vm, &priv->lockState) < 0)
+-        VIR_WARN("Unable to release lease on %s", vm->def->name);
+-    VIR_DEBUG("Preserving lock state '%s'", NULLSTR(priv->lockState));
+-
+     /* suspend vm and send saved data to dst through socket fd */
+     virObjectUnlock(vm);
+     ret = libxlDoMigrateSrcSend(driver, vm, flags, sockfd);
+     virObjectLock(vm);
+ 
+-    if (ret < 0) {
+-        virDomainLockProcessResume(driver->lockManager,
+-                                   "xen:///system",
+-                                   vm,
+-                                   priv->lockState);
++    if (ret == 0) {
++        if (virDomainLockProcessPause(driver->lockManager, vm, &priv->lockState) < 0)
++            VIR_WARN("Unable to release lease on %s", vm->def->name);
++        VIR_DEBUG("Preserving lock state '%s'", NULLSTR(priv->lockState));
++    } else {
+         /*
+          * Confirm phase will not be executed if perform fails. End the
+          * job started in begin phase.

libvirt.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Thu Nov 14 17:31:35 UTC 2019 - James Fehlig <jfehlig@suse.com>
+
+- libxl: Fix lock manager lock ordering
+  2552752f-libxl-fix-lock-manager-lock-ordering.patch
+  bsc#1145774
+
 -------------------------------------------------------------------
 Tue Nov 12 22:51:54 UTC 2019 - James Fehlig <jfehlig@suse.com>
 

libvirt.spec

@@ -338,6 +338,7 @@ Source6:        libvirtd-relocation-server.xml
 Source99:       baselibs.conf
 Source100:      %{name}-rpmlintrc
 # Upstream patches
+Patch0:         2552752f-libxl-fix-lock-manager-lock-ordering.patch
 # Patches pending upstream review
 Patch100:       libxl-dom-reset.patch
 Patch101:       network-don-t-use-dhcp-authoritative-on-static-netwo.patch
@@ -871,6 +872,7 @@ libvirt plugin for NSS for translating domain names into IP addresses.
 
 %prep
 %setup -q
+%patch0 -p1
 %patch100 -p1
 %patch101 -p1
 %patch150 -p1

libxl-set-migration-constraints.patch

@@ -255,7 +255,7 @@ Index: libvirt-5.9.0/src/libxl/libxl_migration.c
  {
      libxlDomainObjPrivatePtr priv = vm->privateData;
      char *hostname = NULL;
-@@ -1246,7 +1267,7 @@ libxlDomainMigrationSrcPerform(libxlDriv
+@@ -1242,7 +1263,7 @@ libxlDomainMigrationSrcPerform(libxlDriv
  
      /* suspend vm and send saved data to dst through socket fd */
      virObjectUnlock(vm);
@@ -263,7 +263,7 @@ Index: libvirt-5.9.0/src/libxl/libxl_migration.c
 +    ret = libxlDoMigrateSrcSend(driver, vm, props, sockfd);
      virObjectLock(vm);
  
-     if (ret < 0) {
+     if (ret == 0) {
 Index: libvirt-5.9.0/src/libxl/libxl_migration.h
 ===================================================================
 --- libvirt-5.9.0.orig/src/libxl/libxl_migration.h