Re: [PATCH v2 4/6] mm: replace vma->vm_flags indirect modification in ksm_madvise

From: Michal Hocko
Date: Wed Jan 25 2023 - 04:39:04 EST


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.

> Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>
--
Michal Hocko
SUSE Labs