[libvirt] [PATCH 1/3] qemuMigrationSrcIsSafe: Check local storage more thoroughly
https://bugzilla.redhat.com/show_bug.cgi?id=1494454
If a domain disk is stored on local filesystem (e.g. ext4) but is
not being migrated it is very likely that domain is not able to
run on destination. Regardless of share/cache mode.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/qemu/qemu_migration.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index b22a327b5..e98b1e4ce 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -1215,25 +1215,26 @@ qemuMigrationSrcIsSafe(virDomainDefPtr def,
virDomainDiskDefPtr disk = def->disks[i];
const char *src = virDomainDiskGetSource(disk);
- /* Our code elsewhere guarantees shared disks are either readonly (in
- * which case cache mode doesn't matter) or used with cache=none or used with
cache=directsync */
+ /* Disks without any source (i.e. floppies and CD-ROMs)
+ * OR readonly are safe. */
if (virStorageSourceIsEmpty(disk->src) ||
- disk->src->readonly ||
- disk->src->shared ||
- disk->cachemode == VIR_DOMAIN_DISK_CACHE_DISABLE ||
- disk->cachemode == VIR_DOMAIN_DISK_CACHE_DIRECTSYNC)
+ disk->src->readonly)
continue;
- /* disks which are migrated by qemu are safe too */
+ /* Disks which are migrated by qemu are safe too. */
if (storagemigration &&
qemuMigrationAnyCopyDisk(disk, nmigrate_disks, migrate_disks))
continue;
+ /* However, disks on local FS (e.g. ext4) are not safe. */
if (virDomainDiskGetType(disk) == VIR_STORAGE_TYPE_FILE) {
- if ((rc = virFileIsSharedFS(src)) < 0)
+ if ((rc = virFileIsSharedFS(src)) < 0) {
return false;
- else if (rc == 0)
- continue;
+ } else if (rc == 0) {
+ virReportError(VIR_ERR_MIGRATE_UNSAFE, "%s",
+ _("Migration without shared storage is
unsafe"));
+ return false;
+ }
if ((rc = virStorageFileIsClusterFS(src)) < 0)
return false;
else if (rc == 1)
@@ -1243,6 +1244,13 @@ qemuMigrationSrcIsSafe(virDomainDefPtr def,
continue;
}
+ /* Our code elsewhere guarantees shared disks are either readonly (in
+ * which case cache mode doesn't matter) or used with cache=none or used with
cache=directsync */
+ if (disk->src->shared ||
+ disk->cachemode == VIR_DOMAIN_DISK_CACHE_DISABLE ||
+ disk->cachemode == VIR_DOMAIN_DISK_CACHE_DIRECTSYNC)
+ continue;
+
virReportError(VIR_ERR_MIGRATE_UNSAFE, "%s",
_("Migration may lead to data corruption if disks"
" use cache != none or cache != directsync"));
--
2.16.1