On Wed, Jan 25, 2023 at 9:08 AM Michal Hocko <mhocko@xxxxxxxx> wrote: > > On Wed 25-01-23 08:57:48, Suren Baghdasaryan wrote: > > On Wed, Jan 25, 2023 at 1:38 AM 'Michal Hocko' via kernel-team > > <kernel-team@xxxxxxxxxxx> wrote: > > > > > > On Wed 25-01-23 00:38:49, Suren Baghdasaryan wrote: > > > > Replace indirect modifications to vma->vm_flags with calls to modifier > > > > functions to be able to track flag changes and to keep vma locking > > > > correctness. Add a BUG_ON check in ksm_madvise() to catch indirect > > > > vm_flags modification attempts. > > > > > > Those BUG_ONs scream to much IMHO. KSM is an MM internal code so I > > > gueess we should be willing to trust it. > > > > Yes, but I really want to prevent an indirect misuse since it was not > > easy to find these. If you feel strongly about it I will remove them > > or if you have a better suggestion I'm all for it. > > You can avoid that by making flags inaccesible directly, right? Ah, you mean Peter's suggestion of using __private? I guess that would cover it. I'll drop these BUG_ONs in the next version. Thanks! > > -- > Michal Hocko > SUSE Labs