Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Sat, 4 May 2019 17:34:40 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Muchun Song <smuchun@gmail.com>
Cc:     rafael@kernel.org,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        zhaowuyun@wingtech.com
Subject: Re: [PATCH] driver core: Fix use-after-free and double free on glue
 directory
Message-ID: <20190504153440.GB19654@kroah.com>
References: <20190423143258.96706-1-smuchun@gmail.com>
 <24b0fff3775147c04b006282727d94fea7f408b4.camel@kernel.crashing.org>
 <CAPSr9jHhwASv7=83hU+81mC0JJyuyt2gGxLmyzpCOfmc9vKgGQ@mail.gmail.com>
 <a37e7a49c3e7fa6ece2be2b76798fef3e51ade4e.camel@kernel.crashing.org>
 <CAPSr9jHCVCHNK+AmKkUBgs4dPC0UC5KdYKqMinkauyL3OL6qrQ@mail.gmail.com>
 <79fbc203bc9fa09d88ab2c4bff8635be4c293d49.camel@kernel.crashing.org>
 <CAPSr9jHw9hgAZo2TuDAKdSLEG1c6EtJG005MWxsxfnbsk1AXow@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <CAPSr9jHw9hgAZo2TuDAKdSLEG1c6EtJG005MWxsxfnbsk1AXow@mail.gmail.com>
User-Agent: Mutt/1.11.4 (2019-03-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Sat, May 04, 2019 at 10:47:07PM +0800, Muchun Song wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> 于2019年5月2日周四 下午2:25写道：
> 
> > > > The basic idea yes, the whole bool *locked is horrid though.
> > > > Wouldn't it
> > > > work to have a get_device_parent_locked that always returns with
> > > > the mutex held,
> > > > or just move the mutex to the caller or something simpler like this
> > > > ?
> > > >
> > >
> > > Greg and Rafael, do you have any suggestions for this? Or you also
> > > agree with Ben?
> >
> > Ping guys ? This is worth fixing...
> 
> I also agree with you. But Greg and Rafael seem to be high latency right now.

It's in my list of patches to get to, sorry, hopefully will dig out of
that next week with the buffer that the merge window provides me.

thanks,

greg k-h