On Wed, Nov 04, 2009 at 03:17:36PM +0200, Michael S. Tsirkin wrote: > On Wed, Nov 04, 2009 at 02:15:33PM +0100, Andi Kleen wrote: > > On Wed, Nov 04, 2009 at 03:08:28PM +0200, Michael S. Tsirkin wrote: > > > On Wed, Nov 04, 2009 at 01:59:57PM +0100, Andi Kleen wrote: > > > > > Fine? > > > > > > > > I cannot say -- are there paths that could drop the device beforehand? > > > > > > Do you mean drop the mm reference? > > > > No the reference to the device, which owns the mm for you. > > The device is created when file is open and destroyed > when file is closed. So I think the fs code handles the > reference counting for me: it won't call file cleanup > callback while some userspace process has the file open. > Right?
Yes. But the semantics when someone inherits such a fd through exec or through file descriptor passing would be surely "interesting" You would still do IO on the old VM. I guess it would be a good way to confuse memory accounting schemes or administrators @) It would be all saner if this was all a single atomic step. -Andi -- a...@linux.intel.com -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
