Messages in this thread | | | From | Thomas Garnier <> | Date | Mon, 7 Nov 2016 14:32:56 -0800 | Subject | Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB |
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On Mon, Nov 7, 2016 at 2:19 PM, Andrew Morton <akpm@linux-foundation.org> wrote: > On Mon, 7 Nov 2016 13:11:14 -0800 Thomas Garnier <thgarnie@google.com> wrote: > >> From: Greg Thelen <gthelen@google.com> >> >> While testing OBJFREELIST_SLAB integration with pagealloc, we found a >> bug where kmem_cache(sys) would be created with both CFLGS_OFF_SLAB & >> CFLGS_OBJFREELIST_SLAB. >> >> The original kmem_cache is created early making OFF_SLAB not possible. >> When kmem_cache(sys) is created, OFF_SLAB is possible and if pagealloc >> is enabled it will try to enable it first under certain conditions. >> Given kmem_cache(sys) reuses the original flag, you can have both flags >> at the same time resulting in allocation failures and odd behaviors. > > Can we please have a better description of the problems which this bug > causes? Without this info it's unclear to me which kernel version(s) > need the fix. > > Given that the bug is 6 months old I'm assuming "not very urgent". >
I will add more details and send another round.
>> This fix discards allocator specific flags from memcg before calling >> create_cache. >> >> Fixes: b03a017bebc4 ("mm/slab: introduce new slab management type, OBJFREELIST_SLAB") >> Signed-off-by: Greg Thelen <gthelen@google.com> >> Tested-by: Thomas Garnier <thgarnie@google.com> > > This should have had your signed-off-by, as you were on the delivery > path. I've made that change.
Thanks Andrew.
-- Thomas
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