On Wed, Feb 19, 2020 at 04:37:11PM -0800, Yang Shi wrote: > On Wed, Feb 19, 2020 at 4:25 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > On Wed, Feb 19, 2020 at 02:46:35PM -0800, Andrew Morton wrote: > > > > > > (switched to email. Please respond via emailed reply-to-all, not via the > > > bugzilla web interface). > > > > > > On Wed, 19 Feb 2020 21:33:32 +0000 bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > > > > > > > https://bugzilla.kernel.org/show_bug.cgi?id=206569 > > > > > > > > --- Comment #1 from Denis Lisov (dennis.lissov@xxxxxxxxx) --- > > > > Upd. Double-checking my kernel settings I found that I've accidentally enabled > > > > experimental CONFIG_READ_ONLY_THP_FOR_FS - may be related to that. > > > > > > > > In my new kernel build the problem failed to reproduce (I've disabled > > > > CONFIG_READ_ONLY_THP_FOR_FS, CONFIG_KSM and switched from > > > > CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS to CONFIG_TRANSPARENT_HUGEPAGE_MADVISE - > > > > sorry for multiple changes). > > > > > > Thanks. > > > > > > Song Liu, could you please take a look? > > > > This is a compound page ... Dennis, are you willing to apply this patch > > https://lore.kernel.org/linux-mm/20200211001536.1027652-12-jhubbard@xxxxxxxxxx/ > > and retest? It will give us more information about what's going on. > > page:ffffc9b318af02c0 refcount:0 mapcount:3 mapping:dead000000000400 > index:0x60b compound_mapcount: 3 > > It looks like a tail page. ... yes, that's the point; that patch prints the information from the head page when the page is a tail page.
