From 6799b72d927015db4ce4cab879f072abc91a41ae Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Tue, 25 Feb 2020 15:53:12 +0100 Subject: [PATCH] qemu: Don't compare local and remote hostnames on migration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Libvirt tries to forbid migration onto the same host and it does that by checking if local and remote hostnames are the same and whether local and remote UUIDs are the same. Well, the latter makes sense but the former doesn't really because libvirtd can be running inside an UTS namespace and hostnames can appear the same on both sides of migration. On the other hand, host UUIDs are unique, so rely on them when trying to prevent migration onto the same host. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1639596 Signed-off-by: Michal Privoznik Reviewed-by: Daniel P. Berrangé --- src/qemu/qemu_migration_cookie.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/src/qemu/qemu_migration_cookie.c b/src/qemu/qemu_migration_cookie.c index a5a9edffc3..1d88ac1d22 100644 --- a/src/qemu/qemu_migration_cookie.c +++ b/src/qemu/qemu_migration_cookie.c @@ -1230,19 +1230,17 @@ qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig, } VIR_FREE(tmp); - /* Check & forbid "localhost" migration */ if (!(mig->remoteHostname = virXPathString("string(./hostname[1])", ctxt))) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("missing hostname element in migration data")); goto error; } - if (STREQ(mig->remoteHostname, mig->localHostname)) { - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Attempt to migrate guest to the same host %s"), - mig->remoteHostname); - goto error; - } + /* Historically, this is the place where we checked whether remoteHostname + * and localHostname are the same. But even if they were, it doesn't mean + * the domain is migrating onto the same host. Rely on UUID which can tell + * for sure. */ + /* Check & forbid localhost migration */ if (!(tmp = virXPathString("string(./hostuuid[1])", ctxt))) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("missing hostuuid element in migration data"));