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From:   Vitaly Wool <vitalywool@gmail.com>
Date:   Sun, 8 Sep 2019 23:44:33 +0300
Message-ID: <CAMJBoFPVmZ=9G0hYz0YYeVH=cMZ=F1urMorvRtm8ZwV7fc4haA@mail.gmail.com>
Subject: Re: [PATCH] z3fold: fix retry mechanism in page reclaim
To:     "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
Cc:     Linux-MM <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        =?UTF-8?Q?Agust=C3=ADn_Dall=CA=BCAlba?= <agustin@dallalba.com.ar>,
        Dan Streetman <ddstreet@ieee.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Markus Linnala <markus.linnala@gmail.com>
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On Sun, Sep 8, 2019 at 4:56 PM Maciej S. Szmigiero
<mail@maciej.szmigiero.name> wrote:
>
> On 08.09.2019 15:29, Vitaly Wool wrote:
> > z3fold_page_reclaim()'s retry mechanism is broken: on a second
> > iteration it will have zhdr from the first one so that zhdr
> > is no longer in line with struct page. That leads to crashes when
> > the system is stressed.
> >
> > Fix that by moving zhdr assignment up.
> >
> > While at it, protect against using already freed handles by using
> > own local slots structure in z3fold_page_reclaim().
> >
> > Reported-by: Markus Linnala <markus.linnala@gmail.com>
> > Reported-by: Chris Murphy <bugzilla@colorremedies.com>
> > Reported-by: Agustin Dall'Alba <agustin@dallalba.com.ar>
> > Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
> > ---
>
> Shouldn't this be CC'ed to stable@ ?

I guess :)

Thanks,
   Vitaly