Il 16/09/2014 14:34, Kevin Wolf ha scritto: > I think bdrv_invalidate_cache() really needs to call bdrv_drain_all() > before starting to reopen stuff. There could be requests in flight > without holding the lock and if you can indeed reopen their BDS under > their feet without breaking things (I doubt it), that would be pure > luck.
But even that's not enough without a lock if .bdrv_invalidate_cache (the callback) is called from a coroutine. As soon as it yields, another request can come in, for example from the NBD server. Paolo