On Wed, Sep 04, 2019 at 03:25:50PM -0700, Ira Weiny wrote: > On Wed, Aug 14, 2019 at 09:23:08AM -0300, Jason Gunthorpe wrote: > > On Tue, Aug 13, 2019 at 01:38:59PM -0700, Ira Weiny wrote: > > > On Tue, Aug 13, 2019 at 03:00:22PM -0300, Jason Gunthorpe wrote: > > > > On Tue, Aug 13, 2019 at 10:41:42AM -0700, Ira Weiny wrote: > > > > > > > > > And I was pretty sure uverbs_destroy_ufile_hw() would take care of (or ensure > > > > > that some other thread is) destroying all the MR's we have associated with this > > > > > FD. > > > > > > > > fd's can't be revoked, so destroy_ufile_hw() can't touch them. It > > > > deletes any underlying HW resources, but the FD persists. > > > > > > I misspoke. I should have said associated with this "context". And of course > > > uverbs_destroy_ufile_hw() does not touch the FD. What I mean is that the > > > struct file which had file_pins hanging off of it would be getting its file > > > pins destroyed by uverbs_destroy_ufile_hw(). Therefore we don't need the FD > > > after uverbs_destroy_ufile_hw() is done. > > > > > > But since it does not block it may be that the struct file is gone before the > > > MR is actually destroyed. Which means I think the GUP code would blow up in > > > that case... :-( > > > > Oh, yes, that is true, you also can't rely on the struct file living > > longer than the HW objects either, that isn't how the lifetime model > > works. > > Reviewing all these old threads... And this made me think. While the HW > objects may out live the struct file. > > They _are_ going away in a finite amount of time right? It is not like they > could be held forever right? Yes, at least until they become shared between FDs Jason