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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Tue, 19 Jun 2018 15:04:56 +0200
Message-ID: <CAHmME9oeoSbRZyf6qJTg+q-zZanYGu4q=YOZNqCCbRAFu15R9w@mail.gmail.com>
Subject: Re: Possible regression in "slab, slub: skip unnecessary kasan_cache_shutdown()"
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To: Dmitry Vyukov <dvyukov@google.com>
Cc: Shakeel Butt <shakeelb@google.com>, aryabinin@virtuozzo.com, Alexander Potapenko <glider@google.com>, cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, Andrew Morton <akpm@linux-foundation.org>, kasan-dev@googlegroups.com, Linux-MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>

HI Dimitry,

On Tue, Jun 19, 2018 at 6:55 AM Dmitry Vyukov <dvyukov@google.com> wrote:
> Your code frees all entries before freeing the cache, right? If you
> add total_entries check before freeing the cache, it does not fire,
> right?

Yes, certainly.

> Are you using SLAB or SLUB? We stress kernel pretty heavily, but with
> SLAB, and I suspect Shakeel may also be using SLAB. So if you are
> using SLUB, there is significant chance that it's a bug in the SLUB
> part of the change.

Nice intuition; I am indeed using SLUB rather than SLAB...

Jason