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    SubjectRe: [PATCH] mm,page_alloc: PF_WQ_WORKER threads must sleep at should_reclaim_retry().
    On Wed, 22 Aug 2018, Tetsuo Handa wrote:

    > On 2018/08/03 15:16, Michal Hocko wrote:
    > > On Fri 03-08-18 07:05:54, Tetsuo Handa wrote:
    > >> On 2018/07/31 14:09, Michal Hocko wrote:
    > >>> On Tue 31-07-18 06:01:48, Tetsuo Handa wrote:
    > >>>> On 2018/07/31 4:10, Michal Hocko wrote:
    > >>>>> Since should_reclaim_retry() should be a natural reschedule point,
    > >>>>> let's do the short sleep for PF_WQ_WORKER threads unconditionally in
    > >>>>> order to guarantee that other pending work items are started. This will
    > >>>>> workaround this problem and it is less fragile than hunting down when
    > >>>>> the sleep is missed. E.g. we used to have a sleeping point in the oom
    > >>>>> path but this has been removed recently because it caused other issues.
    > >>>>> Having a single sleeping point is more robust.
    > >>>>
    > >>>> linux.git has not removed the sleeping point in the OOM path yet. Since removing the
    > >>>> sleeping point in the OOM path can mitigate CVE-2016-10723, please do so immediately.
    > >>>
    > >>> is this an {Acked,Reviewed,Tested}-by?
    > >>>
    > >>> I will send the patch to Andrew if the patch is ok.
    > >>>
    > >>>> (And that change will conflict with Roman's cgroup aware OOM killer patchset. But it
    > >>>> should be easy to rebase.)
    > >>>
    > >>> That is still a WIP so I would lose sleep over it.
    > >>>
    > >>
    > >> Now that Roman's cgroup aware OOM killer patchset will be dropped from linux-next.git ,
    > >> linux-next.git will get the sleeping point removed. Please send this patch to linux-next.git .
    > >
    > > I still haven't heard any explicit confirmation that the patch works for
    > > your workload. Should I beg for it? Or you simply do not want to have
    > > your stamp on the patch? If yes, I can live with that but this playing
    > > hide and catch is not really a lot of fun.
    > >
    >
    > I noticed that the patch has not been sent to linux-next.git yet.
    > Please send to linux-next.git without my stamp on the patch.
    >

    For those of us who are tracking CVE-2016-10723 which has peristently been
    labeled as "disputed" and with no clear indication of what patches address
    it, I am assuming that commit 9bfe5ded054b ("mm, oom: remove sleep from
    under oom_lock") and this patch are the intended mitigations?

    A list of SHA1s for merged fixed and links to proposed patches to address
    this issue would be appreciated.

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