3.16.36-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Konstantin Khlebnikov <[email protected]> commit 4d88e6f7d5ffc84e6094a47925870f4a130555c2 upstream. If CONFIG_BALLOON_COMPACTION=n balloon_page_insert() does not link pages with balloon and doesn't set PagePrivate flag, as a result balloon_page_dequeue() cannot get any pages because it thinks that all of them are isolated. Without balloon compaction nobody can isolate ballooned pages. It's safe to remove this check. Fixes: d6d86c0a7f8d ("mm/balloon_compaction: redesign ballooned pages management"). Signed-off-by: Konstantin Khlebnikov <[email protected]> Reported-by: Matt Mullins <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: jian wang <[email protected]> --- mm/balloon_compaction.c | 2 ++ 1 file changed, 2 insertions(+) --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -94,11 +94,13 @@ struct page *balloon_page_dequeue(struct * to be released by the balloon driver. */ if (trylock_page(page)) { +#ifdef CONFIG_BALLOON_COMPACTION if (!PagePrivate(page)) { /* raced with isolation */ unlock_page(page); continue; } +#endif balloon_page_delete(page); unlock_page(page); dequeued_page = true;
