migration: Fail migration on bdrv_flush_all() error

If bdrv_flush_all() returns an error, there is an inconsistency in the
view of an image file between the source and the destination host.
Completing the migration would lead to corruption. Better abort
migration in this case.

To reproduce this case, try the following (ensures that there is
something to flush, and then fails that flush):

$ qemu-img create -f qcow2 test.qcow2 1G
$ cat blkdebug.cfg
[inject-error]
event = "flush_to_os"
errno = "5"
$ qemu-system-x86_64 -hda blkdebug:blkdebug.cfg:test.qcow2 -monitor stdio
(qemu) qemu-io ide0-hd0 "write 0 4k"
(qemu) migrate ...

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Kevin Wolf 2013-07-05 13:54:55 +02:00
parent 5698346391
commit 0e1146a7a0
1 changed files with 14 additions and 3 deletions

View File

@ -527,15 +527,26 @@ static void *migration_thread(void *opaque)
if (pending_size && pending_size >= max_size) {
qemu_savevm_state_iterate(s->file);
} else {
int ret;
DPRINTF("done iterating\n");
qemu_mutex_lock_iothread();
start_time = qemu_get_clock_ms(rt_clock);
qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
old_vm_running = runstate_is_running();
vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
qemu_file_set_rate_limit(s->file, INT_MAX);
qemu_savevm_state_complete(s->file);
ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
if (ret >= 0) {
qemu_file_set_rate_limit(s->file, INT_MAX);
qemu_savevm_state_complete(s->file);
}
qemu_mutex_unlock_iothread();
if (ret < 0) {
migrate_finish_set_state(s, MIG_STATE_ERROR);
break;
}
if (!qemu_file_get_error(s->file)) {
migrate_finish_set_state(s, MIG_STATE_COMPLETED);
break;