[Qemu-devel] Block live migration's use of type hint

[Markus Armbruster]

Block live migration appears to migrate only block devices with type
hint BDRV_TYPE_HD.  Others are silently skipped:

static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
{
    Monitor *mon = opaque;
    BlkMigDevState *bmds;
    int64_t sectors;

    if (bs->type == BDRV_TYPE_HD) {
[...]
    }
}

The logic comes from commit c163b5ca, but its commit message doesn't
mention it.  Liran, please advise.  What are we trying to accomplish
here?

Whatever it is, I suspect checking the type hint isn't the appropriate
way to get it.