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Date:   Wed, 28 Jun 2023 09:41:31 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     akpm@linux-foundation.org, willy@infradead.org, hannes@cmpxchg.org,
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Subject: Re: [PATCH v4 3/6] mm: drop per-VMA lock when returning
 VM_FAULT_RETRY or VM_FAULT_COMPLETED
Message-ID: <ZJw4i67FKlsvIiV3@x1n>
References: <20230628071800.544800-1-surenb@google.com>
 <20230628071800.544800-4-surenb@google.com>
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On Wed, Jun 28, 2023 at 12:17:57AM -0700, Suren Baghdasaryan wrote:
> handle_mm_fault returning VM_FAULT_RETRY or VM_FAULT_COMPLETED means
> mmap_lock has been released. However with per-VMA locks behavior is
> different and the caller should still release it. To make the
> rules consistent for the caller, drop the per-VMA lock when returning
> VM_FAULT_RETRY or VM_FAULT_COMPLETED. Currently the only path returning
> VM_FAULT_RETRY under per-VMA locks is do_swap_page and no path returns
> VM_FAULT_COMPLETED for now.
> 
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>

Acked-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu