Re: [PATCH] mm: Fix the pgtable leak

[Minchan Kim]

On Wed, Feb 13, 2019 at 01:24:58PM +0100, Michal Hocko wrote:
> On Wed 13-02-19 21:12:00, Minchan Kim wrote:
> > On Wed, Feb 13, 2019 at 01:03:30PM +0100, Michal Hocko wrote:
> > > On Wed 13-02-19 20:29:00, Minchan Kim wrote:
> > > > [1] was backported to v4.9 stable tree but it introduces pgtable
> > > > memory leak because with fault retrial, preallocated pagetable
> > > > could be leaked in second iteration.
> > > > To fix the problem, this patch backport [2].
> > > > 
> > > > [1] 5cf3e5ff95876, mm, memcg: fix reclaim deadlock with writeback
> > > > [2] b0b9b3df27d10, mm: stop leaking PageTables
> > > > 
> > > > Fixes: 5cf3e5ff95876 ("mm, memcg: fix reclaim deadlock with writeback")
> > > > Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> > > > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> > > > Cc: Michal Hocko <mhocko@xxxxxxxx>
> > > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > > > Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> > > > Cc: Liu Bo <bo.liu@xxxxxxxxxxxxxxxxx>
> > > > Cc: <stable@xxxxxxxxxxxxxxx> [4.9]
> > > > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
> > > 
> > > Thanks for catching this dependency. Do I assume it correctly that this
> > > is stable-4.9 only?
> > 
> > I have no idea how I could find it automatically that a stable patch of
> > linus tree is spread out with several stable trees(Hope Greg has an
> > answer). I just checked 4.4 longterm kernel and couldn't find it in there.
> 
> See http://lkml.kernel.org/r/20190115174036.GA24149@xxxxxxxxxxxxxx
> 
> But my question was more about "this is a stable only thing"? It was not
> obvious from the subject so I wanted to be sure that I am not missing
> anything.

Yub, I think only 4.9 stable tree need to be fixed because Hugh's patch was
in there since v4.10. 

Thanks.