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Date:   Fri, 4 Aug 2023 12:14:16 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     torvalds@linux-foundation.org, jannh@google.com,
        willy@infradead.org, liam.howlett@oracle.com, david@redhat.com,
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        hannes@cmpxchg.org, dave@stgolabs.net, hughd@google.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        stable@vger.kernel.org, kernel-team@android.com,
        Linus Torvalds <torvalds@linuxfoundation.org>
Subject: Re: [PATCH v4 1/6] mm: enable page walking API to lock vmas during
 the walk
Message-Id: <20230804121416.533bb81336ded8f170da097e@linux-foundation.org>
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On Fri,  4 Aug 2023 08:27:19 -0700 Suren Baghdasaryan <surenb@google.com> wrote:

> walk_page_range() and friends often operate under write-locked mmap_lock.
> With introduction of vma locks, the vmas have to be locked as well
> during such walks to prevent concurrent page faults in these areas.
> Add an additional member to mm_walk_ops to indicate locking requirements
> for the walk.
> 
> ...
>
>  18 files changed, 100 insertions(+), 20 deletions(-)
> 

That's a big patch for a -stable backport.

Presumably the various -stable maintainers will be wondering why we're
doing this.  But, as is so often the case, the changelog fails to
describe any user-visible effects of the change.  Please send this info
and I'll add it to the changelog.