Re: [PATCH v5 3/3] userfaultfd: use per-vma locks in userfaultfd operations

[Liam R. Howlett]

* Suren Baghdasaryan <surenb@xxxxxxxxxx> [240213 13:57]:
..

> >
> > Yes, I don't think we should be locking the mm in lock_vma(), as it
> > makes things hard to follow.
> >
> > We could use something like uffd_prepare(), uffd_complete() but I
> > thought of those names rather late in the cycle, but I've already caused
> > many iterations of this patch set and that clean up didn't seem as vital
> > as simplicity and clarity of the locking code.
> 
> Maybe lock_vma_for_uffd()/unlock_vma_for_uffd()? Whatever name is
> better I'm fine with it but all these #ifdef's sprinkled around don't
> contribute to the readability.

The issue I have is the vma in the name - we're not doing anything to
the vma when we mmap_lock.

> Anyway, I don't see this as a blocker, just nice to have.

Yes, that's how I see it as well.