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Date:   Thu, 30 Sep 2021 13:10:39 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] x86/process: directly use try_get_task_stack()
 return value in get_wchan
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On Thu, Sep 30, 2021 at 06:52:29PM +0800, Jisheng Zhang wrote:
> try_get_task_stack() has already properly gets target task's stack,
> no need to call task_stack_page() again.

Please see:

  https://lkml.kernel.org/r/20210929220218.691419-1-keescook@chromium.org

Whichever way around, this code doesn't live much longer.