Re: [PATCH] mm: fix long time stall from mm_populate

[Matthew Wilcox <willy@xxxxxxxxxxxxx>]

On Mon, Feb 10, 2020 at 04:19:58PM -0800, Minchan Kim wrote:
>       filemap_fault
>         find a page form page(PG_uptodate|PG_readahead|PG_writeback)

Uh ... That shouldn't be possible.

        /*
         * Same bit is used for PG_readahead and PG_reclaim.
         */
        if (PageWriteback(page))
                return;

        ClearPageReadahead(page);