Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB

From	Andrew Morton <akpm@linux-foundation.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB
Date	2016-11-07 23:50 +0100
Message-ID	<sB0TL-12R-3@gated-at.bofh.it> (permalink)
References	<sAZuG-bB-9@gated-at.bofh.it> <sB0K5-ZI-1@gated-at.bofh.it> <sB0K6-ZI-17@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On Mon, 7 Nov 2016 14:32:56 -0800 Thomas Garnier <thgarnie@google.com> wrote:

> 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.

Please simply send the additional changelog text in this thread -
processing an entire v4 patch just for a changelog fiddle is rather
heavyweight.

Thread

[PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB Thomas Garnier <thgarnie@google.com> - 2016-11-07 22:50 +0100
  Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB  & OBJFREELIST_SLAB Andrew Morton <akpm@linux-foundation.org> - 2016-11-07 23:40 +0100
    Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB Thomas Garnier <thgarnie@google.com> - 2016-11-07 23:40 +0100
      Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB  & OBJFREELIST_SLAB Andrew Morton <akpm@linux-foundation.org> - 2016-11-07 23:50 +0100
        Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB & OBJFREELIST_SLAB Thomas Garnier <thgarnie@google.com> - 2016-11-08 05:30 +0100
        Re: [PATCH v3 1/2] memcg: Prevent memcg caches to be both OFF_SLAB  & OBJFREELIST_SLAB Christoph Lameter <cl@linux.com> - 2016-11-09 01:00 +0100

csiph-web