Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH 1/5] USB: serial: f81232: clear overrun flag
To:     Oliver Neukum <oneukum@suse.com>, johan@kernel.org
Cc:     peter_hong@fintek.com.tw,
        "Ji-Ze Hong (Peter Hong)" <hpeter+linux_kernel@gmail.com>,
        gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org
References: <1516607927-8887-1-git-send-email-hpeter+linux_kernel@gmail.com>
 <1516615597.7580.7.camel@suse.com>
From:   "Ji-Ze Hong (Peter Hong)" <hpeter@gmail.com>
Message-ID: <42995e53-a110-a0fa-da47-4ebe35272812@gmail.com>
Date:   Tue, 23 Jan 2018 09:50:48 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101
 Thunderbird/52.5.2
MIME-Version: 1.0
In-Reply-To: <1516615597.7580.7.camel@suse.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Oliver,

Oliver Neukum 於 2018/1/22 下午 06:06 寫道:
>> +static void f81232_lsr_worker(struct work_struct *work)
>> +{
>> +	struct f81232_private *priv;
>> +	struct usb_serial_port *port;
>> +	int status;
>> +	u8 tmp;
>> +
>> +	priv = container_of(work, struct f81232_private, lsr_work);
>> +	port = priv->port;
>> +
>> +	status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
>> +	if (status)
>> +		dev_warn(&port->dev, "read LSR failed: %d\n", status);
>> +}
> 
> Hi,
> 
> I am afraid this is incomplete. You are scheduling a work that does IO.
> Hence you must cancel that work when the driver is unbound from the
> interface. You must also not do IO like this while the system is suspending.

We'll add cancel worker operation on close() and suspend() to prevent
from I/O operations in wrong time with next patch version.

Thanks
-- 
With Best Regards,
Peter Hong