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charset=us-ascii Content-Disposition: inline In-Reply-To: <20191018163754.3736610-1-songliubraving@fb.com> User-Agent: Mutt/1.12.2 (2019-09-21) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Oct 18, 2019 at 09:37:54AM -0700, Song Liu wrote: > In collapse_file(), after locking the page, it is necessary to recheck > that the page is up-to-date. Add PageUptodate() check for both shmem THP > and file THP. > > Current khugepaged should not try to collapse dirty file THP, because it > is limited to read only text. Add a PageDirty check and warning for file > THP. This is added after page_mapping() check, because if the page is > truncated, it might be dirty. > > Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") > Cc: Kirill A. Shutemov > Cc: Johannes Weiner > Cc: Hugh Dickins > Cc: William Kucharski > Cc: Andrew Morton > Signed-off-by: Song Liu Acked-by: Johannes Weiner