On 12/16/16 2:15 AM, Christoph Hellwig wrote: > On Thu, Dec 15, 2016 at 10:16:23AM +0100, Zdenek Kabelac wrote: >> So let me explain the logic behind this 'amazingly stupid' idea. > > And that logic doesn't make any sense at all. invibly unmounting > a file system behind the users back is actively harmful, as it is > contradicting the principle of least surprise, and the xfstests mess > is one simple example for it. Add a callback in-kernel to tell the > fs to shut down but NOT unmount and expose the namespace below it, > which the administrator has probably intentionally hid. > > Even worse unmount may trigger further writes and with fses not > handling them the fs might now be stuck after being detached from > the namespace without a way for the admin to detect or recover this. > > What XFS did on IRIX was to let the volume manager call into the fs > and shut it down. At this point no further writes are possible, > but we do not expose the namespace under the mount point, and the > admin can fix the situation with all the normal tools. <late to the party> Is there a need for this kind of call-up when xfs now has the configurable error handling so that it will shut down after X retries or Y seconds of a persistent error? -Eric -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
