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

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Message-ID: <Y9D4rWEsajV/WfNx@dhcp22.suse.cz>
Date:   Wed, 25 Jan 2023 10:38:53 +0100
From:   Michal Hocko <mhocko@...e.com>
To:     Suren Baghdasaryan <surenb@...gle.com>
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Subject: Re: [PATCH v2 4/6] mm: replace vma->vm_flags indirect modification
 in ksm_madvise

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@...gle.com>

Acked-by: Michal Hocko <mhocko@...e.com>
-- 
Michal Hocko
SUSE Labs