Date:   Thu, 9 Mar 2023 11:58:18 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc:     Peter Xu <peterx@redhat.com>, David Hildenbrand <david@redhat.com>,
        =?UTF-8?Q?Micha=C5=82_Miros=C5=82aw?= <emmir@google.com>,
        Andrei Vagin <avagin@gmail.com>,
        Danylo Mocherniuk <mdanylo@google.com>,
        Paul Gofman <pgofman@codeweavers.com>,
        Cyrill Gorcunov <gorcunov@gmail.com>,
        Mike Rapoport <rppt@kernel.org>, Nadav Amit <namit@vmware.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Shuah Khan <shuah@kernel.org>,
        Christian Brauner <brauner@kernel.org>,
        Yang Shi <shy828301@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Liam R . Howlett" <Liam.Howlett@Oracle.com>,
        Yun Zhou <yun.zhou@windriver.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Alex Sierra <alex.sierra@amd.com>,
        Matthew Wilcox <willy@infradead.org>,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        "Gustavo A . R . Silva" <gustavoars@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, linux-kselftest@vger.kernel.org,
        Greg KH <gregkh@linuxfoundation.org>, kernel@collabora.com
Subject: Re: [PATCH v11 0/7] Implement IOCTL to get and optionally clear
 info about PTEs
Message-Id: <20230309115818.170dd5ef2cde7b58b9354ecd@linux-foundation.org>
In-Reply-To: <20230309135718.1490461-1-usama.anjum@collabora.com>
References: <20230309135718.1490461-1-usama.anjum@collabora.com>
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On Thu,  9 Mar 2023 18:57:11 +0500 Muhammad Usama Anjum <usama.anjum@collabora.com> wrote:

> The information related to pages if the page is file mapped, present and
> swapped is required for the CRIU project [5][6]. The addition of the
> required mask, any mask, excluded mask and return masks are also required
> for the CRIU project [5].

It's a ton of new code and what I'm not seeing in here (might have
missed it?) is a clear statement of the value of this feature to our
users.

I see hints that CRIU would like it, but no description of how valuable
this is to CRIU's users.

So please spend some time preparing this info.

Also, are any other applications of this feature anticipated?  If so,
what are they?

IOW, please sell this stuff to us!