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Subject: Re: [PATCH] driver core: Fix use-after-free and double free on glue
 directory
To:     Greg KH <gregkh@linuxfoundation.org>,
        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, linux-arm-msm@vger.kernel.org
References: <20190423143258.96706-1-smuchun@gmail.com>
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 <CAPSr9jHw9hgAZo2TuDAKdSLEG1c6EtJG005MWxsxfnbsk1AXow@mail.gmail.com>
 <20190504153440.GB19654@kroah.com>
From:   Gaurav Kohli <gkohli@codeaurora.org>
Message-ID: <e79201c2-a00b-d226-adc2-62769ae1ad81@codeaurora.org>
Date:   Thu, 9 May 2019 20:08:02 +0530
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Hi ,

Last patch will serialize the addition of child to parent directory, 
won't it affect performance.

Regards
Gaurav

On 5/4/2019 9:04 PM, Greg KH wrote:
> 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
> 

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