On Mon, Apr 10, 2017 at 06:13:59PM +0200, Michal Hocko wrote: > On Mon 10-04-17 18:04:51, Greg KH wrote: > > On Mon, Apr 10, 2017 at 04:48:17PM +0100, Ben Hutchings wrote: > > > On Mon, 2017-04-10 at 17:09 +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > > > This is a note to let you know that I've just added the patch titled > > > > > > > > mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp > > > > > > > > to the 4.4-stable tree which can be found at: > > > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary > > > > > > > > The filename of the patch is: > > > > mm-huge_memory.c-respect-foll_force-foll_cow-for-thp.patch > > > > and it can be found in the queue-4.4 subdirectory. > > > > > > > > If you, or anyone else, feels it should not be added to the stable tree, > > > > please let <stable@xxxxxxxxxxxxxxx> know about it. > > > > > > > > > > > > From 303681d5d538d81b5e23754515202b5b9febd2e9 Mon Sep 17 00:00:00 2001 > > > > From: Keno Fischer <keno@xxxxxxxxxxxxxxxxxx> > > > > Date: Tue, 24 Jan 2017 15:17:48 -0800 > > > > Subject: mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp > > > > > > > > From: Keno Fischer <keno@xxxxxxxxxxxxxxxxxx> > > > > > > > > commit 8310d48b125d19fcd9521d83b8293e63eb1646aa upstream. > > > [...] > > > > - Drop change to follow_devmap_pmd() > > > > - pmd_dirty() is not available; check the page flags as in older > > > > backports of can_follow_write_pte() > > > > - Adjust context] > > > [...] > > > > > > Aside from the fact that I got this backport wrong, I don't think you > > > need the main change here. In 4.4, all arches that define > > > CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE also define pmd_dirty(). > > > > Hm, ok, but Keno said people are still hitting this issue on 4.4-stable. > > > > So, what should I do? I'll go drop this from my queue for now, but as I > > don't know what to do to test this, I'm at a loss... > > The changelog of the said patch contains the reproducer... Hah, I should have seen that :) I'll wait a bit for this one, if I get some time later this week, I'll work on the fixed up backport. Unless Keno wants to provide it? (hint...) thanks, greg k-h