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Subject: Re: [question] De-registration does not remove port
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     vgupta@synopsys.com, Jiri Slaby <jirislaby@kernel.org>,
        linux-snps-arc@lists.infradead.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org,
        Pavel Andrianov <andrianov@ispras.ru>
References: <3e131267-e1b3-1b83-f8be-0577da479223@gmail.com>
 <YNLfcKFL1LkJgXAR@kroah.com>
From:   Saubhik Mukherjee <saubhik.mukherjee@gmail.com>
Message-ID: <7af6c0a5-c990-5a40-104e-13f44b1cb4c5@gmail.com>
Date:   Thu, 24 Jun 2021 18:33:01 +0530
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On 6/23/21 12:44 PM, Greg KH wrote:
> On Wed, Jun 23, 2021 at 11:42:36AM +0530, Saubhik Mukherjee wrote:
>> In drivers/tty/serial/arc_uart.c, arc_serial_remove always returns 0,
>> instead of calling uart_remove_one_port to remove uart port from serial
>> core. The comment says "This will be never be called". In my understanding,
>> a port added using uart_add_one_port should be removed during
>> de-registration.
>>
>> Is there a reason for this behavior?
> 
> Did you test the code to see if that function will ever be called?

I would like to reformulate the question: Suppose arc_serial_remove is 
never called. Then I would like to know how the driver de-registration 
is organized since the UART port is never removed?