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Date:   Tue, 23 Aug 2022 08:20:50 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     lily <floridsleeves@gmail.com>
Cc:     linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        jirislaby@kernel.org
Subject: Re: [PATCH v1] drivers/tty/serial: check the return value of
 uart_port_check()
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On Mon, Aug 22, 2022 at 10:57:39PM -0700, lily wrote:
> uart_port_check() can return NULL pointer.

It can?  How will that happen?

> Check its return value
> before dereference it.

How do you trigger this issue, and how was this change you made tested?

thanks,

greg k-h