From: Muchun Song <songmuchun@bytedance.com>
To: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>,
Dmitry Vyukov <dvyukov@google.com>,
Andrew Morton <akpm@linux-foundation.org>,
kasan-dev <kasan-dev@googlegroups.com>,
Linux Memory Management List <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>,
Xiongchun duan <duanxiongchun@bytedance.com>
Subject: Re: [PATCH v2] mm: kfence: fix objcgs vector allocation
Date: Mon, 28 Mar 2022 23:54:12 +0800 [thread overview]
Message-ID: <CAMZfGtVkp+xCM3kgLHRNRFUs_fus0f3Ry_jFv8QaSWLfnkXREg@mail.gmail.com> (raw)
In-Reply-To: <CAMZfGtWfudKnm71uNQtS-=+3_m25nsfPDo8-vZYzrktQbxHUMA@mail.gmail.com>
On Mon, Mar 28, 2022 at 11:51 PM Muchun Song <songmuchun@bytedance.com> wrote:
>
> On Mon, Mar 28, 2022 at 11:43 PM Marco Elver <elver@google.com> wrote:
> >
> > On Mon, 28 Mar 2022 at 15:28, Muchun Song <songmuchun@bytedance.com> wrote:
> > >
> > > If the kfence object is allocated to be used for objects vector, then
> > > this slot of the pool eventually being occupied permanently since
> > > the vector is never freed. The solutions could be 1) freeing vector
> > > when the kfence object is freed or 2) allocating all vectors statically.
> > > Since the memory consumption of object vectors is low, it is better to
> > > chose 2) to fix the issue and it is also can reduce overhead of vectors
> > > allocating in the future.
> > >
> > > Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB")
> > > Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> >
> > Reviewed-by: Marco Elver <elver@google.com>
>
> Thanks.
>
> >
> > Btw, how did you test this?
> >
I have tested it with syzkaller with the following configs.
And I didn't find any issues.
CONFIG_KFENCE=y
CONFIG_KFENCE_SAMPLE_INTERVAL=10
CONFIG_KFENCE_NUM_OBJECTS=2550
CONFIG_KFENCE_DEFERRABLE=n
CONFIG_KFENCE_STATIC_KEYS=y
CONFIG_KFENCE_STRESS_TEST_FAULTS=0
next prev parent reply other threads:[~2022-03-28 15:54 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-28 13:28 [PATCH v2] mm: kfence: fix objcgs vector allocation Muchun Song
2022-03-28 15:43 ` Marco Elver
2022-03-28 15:51 ` Muchun Song
2022-03-28 15:54 ` Muchun Song [this message]
2022-03-28 18:57 ` Marco Elver
2022-03-29 3:01 ` [External] " Muchun Song
2022-03-28 19:26 ` Roman Gushchin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAMZfGtVkp+xCM3kgLHRNRFUs_fus0f3Ry_jFv8QaSWLfnkXREg@mail.gmail.com \
--to=songmuchun@bytedance.com \
--cc=akpm@linux-foundation.org \
--cc=duanxiongchun@bytedance.com \
--cc=dvyukov@google.com \
--cc=elver@google.com \
--cc=glider@google.com \
--cc=kasan-dev@googlegroups.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).