On Mon, Oct 19, 2015 at 03:31:42PM +0900, Minchan Kim wrote: > Hello, it's too late since I sent previos patch. > https://lkml.org/lkml/2015/6/3/37 > > This patch is alomost new compared to previos approach. > I think this is more simple, clear and easy to review. > > One thing I should notice is that I have tested this patch > and couldn't find any critical problem so I rebased patchset > onto recent mmotm(ie, mmotm-2015-10-15-15-20) to send formal > patchset. Unfortunately, I start to see sudden discarding of > the page we shouldn't do. IOW, application's valid anonymous page > was disappeared suddenly. > > When I look through THP changes, I think we could lose > dirty bit of pte between freeze_page and unfreeze_page > when we mark it as migration entry and restore it. > So, I added below simple code without enough considering > and cannot see the problem any more. > I hope it's good hint to find right fix this problem. > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index d5ea516ffb54..e881c04f5950 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -3138,6 +3138,9 @@ static void unfreeze_page_vma(struct vm_area_struct *vma, struct page *page, > if (is_write_migration_entry(swp_entry)) > entry = maybe_mkwrite(entry, vma); > > + if (PageDirty(page)) > + SetPageDirty(page); The condition of PageDirty was typo. I didn't add the condition. Just added. SetPageDirty(page); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>