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Date:   Mon, 9 Oct 2023 11:38:51 +0300
From:   Mike Rapoport <rppt@kernel.org>
To:     Axel Rasmussen <axelrasmussen@google.com>
Cc:     Alejandro Colomar <alx@kernel.org>, Peter Xu <peterx@redhat.com>,
        linux-man@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/10] userfaultfd.2: briefly mention two-step feature
 handshake process
Message-ID: <20231009083851.GF3303@kernel.org>
References: <20230919190206.388896-1-axelrasmussen@google.com>
 <20230919190206.388896-2-axelrasmussen@google.com>
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On Tue, Sep 19, 2023 at 12:01:57PM -0700, Axel Rasmussen wrote:
> This process is critical for programs which depend on extra features, so
> it's worth mentioning here.
> 
> Future commits will much more fully describe it in ioctl_userfaultfd.2.
> 
> Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>

Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>

> ---
>  man2/userfaultfd.2 | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/man2/userfaultfd.2 b/man2/userfaultfd.2
> index 40354065c..1b2af22f9 100644
> --- a/man2/userfaultfd.2
> +++ b/man2/userfaultfd.2
> @@ -200,8 +200,9 @@ the application must enable it using the
>  .B UFFDIO_API
>  .BR ioctl (2)
>  operation.
> -This operation allows a handshake between the kernel and user space
> -to determine the API version and supported features.
> +This operation allows a two-step handshake between the kernel and user space
> +to determine what API version and features the kernel supports,
> +and then to enable those features user space wants.
>  This operation must be performed before any of the other
>  .BR ioctl (2)
>  operations described below (or those operations fail with the
> -- 
> 2.42.0.459.ge4e396fd5e-goog
> 
> 

-- 
Sincerely yours,
Mike.