On 05/25/2018 09:43 PM, Andrew Morton wrote: > On Fri, 25 May 2018 15:08:53 +0200 Vlastimil Babka <vbabka@xxxxxxx> wrote: > >> we might consider this for 4.17 although I don't know if there's anything >> currently broken. Stable backports should be more important, but will have to >> be reviewed carefully, as the code went through many changes. >> BTW I think that also the ac->preferred_zoneref reset is currently useless if >> we don't also reset ac->nodemask from a mempolicy to NULL first (which we >> probably should for the OOM victims etc?), but I would leave that for a >> separate patch. > > Confused. If nothing is currently broken then why is a backport > needed? Presumably because we expect breakage in the future? Can you > expand on this? I mean that SLAB is currently not affected, but in older kernels than 4.7 that don't yet have 511e3a058812 ("mm/slab: make cache_grow() handle the page allocated on arbitrary node") it is. That's at least 4.4 LTS. Older ones I'll have to check.