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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Chao Liu <liuchao173@huawei.com>, linux-kernel@vger.kernel.org,
        hewenliang4@huawei.com
Cc:     steven.price@arm.com, Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] cpu/hotplug: check the return value of idle_thread_get
In-Reply-To: <20230327203728.159123-1-liuchao173@huawei.com>
References: <20230327203728.159123-1-liuchao173@huawei.com>
Date:   Wed, 18 May 2022 10:55:37 +0200
Message-ID: <87leuzjk3a.ffs@tglx>
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On Mon, Mar 27 2023 at 20:37, Chao Liu wrote:
> ilde may be ERR_PTR()

Yes, but if that happens in bringup_cpu() or finish_cpu() it would be a
serious bug and the error pointer dereference would be the least of the
problems.

If the initial check in _cpu_up() failed for a CPU then the above
functions cannot be invoked for that CPU ever.

Thanks,

        tglx