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From:   Oleksandr Natalenko <oleksandr@redhat.com>
Date:   Fri, 23 Mar 2018 09:42:35 +0100
Message-ID: <CAHcwAbQ4y3vWp7p7GayfdbzbomLrqLKMfu0egEoEODJ3LN5qOw@mail.gmail.com>
Subject: Re: [PATCH v2] vmw_balloon: fixing double free when batching mode is off
To:     Nadav Amit <namit@vmware.com>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Xavier Deguillard <xdeguillard@vmware.com>,
        pv-drivers <pv-drivers@vmware.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Gil Kupfer <gilkup@gmail.com>,
        "stable@vger.kernel.org" <stable@vger.kernel.org>,
        "ldu@redhat.com" <ldu@redhat.com>
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Hi.

On Thu, Mar 22, 2018 at 9:02 PM, Nadav Amit <namit@vmware.com> wrote:
> Actually, rechecking the bug description, I might have rushed. The bug that
> I encountered is related to the vunmap() but it is only caused when batching
> is off, while the bug you reported has batching on.
>
> It seems that your sources support batching but do not include b91f108a3d54
> (“VMware balloon: Treat init like reset”), which I think would have solved
> the problem. I don’t see a mainline kernel that supports batching and does
> not have this patch, so it would be helpful to see the exact module that you
> use.

Correct. The hash is d7568c130d0d0ff1fc5b364fc879b91f108a3d54, actually, though.
Yes, we miss this commit in our code base, but also we've already
provided a test kernel
with this commit included to the customer. Unfortunately, we have no answer yet.

-- 
Best regards,
  Oleksandr Natalenko (post-factum)
  Software Maintenance Engineer