Date: Tue, 16 Jan 2018 10:20:08 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: "Kohli, Gaurav" <gkohli@codeaurora.org>
Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org
Subject: Re: Query: Crash is coming during /prod/PID/stat and do_exit of same
 task
Message-ID: <20180116072008.GA6918@avx2>
References: <20180110052017.GB2829@avx2>
 <c43519cb-ce67-96ec-5c55-34b258e47d60@codeaurora.org>
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On Tue, Jan 16, 2018 at 11:06:47AM +0530, Kohli, Gaurav wrote:
> On 1/10/2018 10:50 AM, Alexey Dobriyan wrote:
> 
> >> We are seeing crash in do_task_stat while accessing stack pointer, It
> >> seems same task has already completed do_exit call.
> >> So it seems a race between them:
> > Please, post exact kernel version and struct task_struct::usage if you
> > still have that kernel core (or even full task_struct)
> 
> Hi Alexey,
> 
> We are working on 4.9.65 and Please find below usage value and other task_struct value,
> please let me know if some other data required as well.

Kernel stacks live their own lives nowadays, the code needs try_get_task_stack().