Date:   Mon, 6 Mar 2023 20:23:36 -0500
From:   Peter Xu <peterx@redhat.com>
To:     Axel Rasmussen <axelrasmussen@google.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>, Jan Kara <jack@suse.cz>,
        "Liam R. Howlett" <Liam.Howlett@oracle.com>,
        Matthew Wilcox <willy@infradead.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Mike Rapoport <rppt@kernel.org>,
        Muchun Song <muchun.song@linux.dev>,
        Nadav Amit <namit@vmware.com>, Shuah Khan <shuah@kernel.org>,
        James Houghton <jthoughton@google.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v3 5/5] mm: userfaultfd: add UFFDIO_CONTINUE_MODE_WP to
 install WP PTEs
Message-ID: <ZAaSGGzylNFCR+ql@x1n>
References: <20230306225024.264858-1-axelrasmussen@google.com>
 <20230306225024.264858-6-axelrasmussen@google.com>
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On Mon, Mar 06, 2023 at 02:50:24PM -0800, Axel Rasmussen wrote:
> UFFDIO_COPY already has UFFDIO_COPY_MODE_WP, so when installing a new
> PTE to resolve a missing fault, one can install a write-protected one.
> This is useful when using UFFDIO_REGISTER_MODE_{MISSING,WP} in
> combination.
> 
> So, add an analogous UFFDIO_CONTINUE_MODE_WP, which does the same thing
> but for *minor* faults.
> 
> Update the selftest to do some very basic exercising of the new flag.
> 
> Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>

Some mentioning on the use case would be nice. :) No objection having it.

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

Thanks,

-- 
Peter Xu