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References: <20240116141801.396398-1-khtsai@google.com> <02bec7b8-7754-4b9d-84ae-51621d6aa7ec@kernel.org>
 <2024012724-chirpy-google-51bb@gregkh>
In-Reply-To: <2024012724-chirpy-google-51bb@gregkh>
From: Kuen-Han Tsai <khtsai@google.com>
Date: Sun, 28 Jan 2024 22:00:49 +0800
Message-ID: <CAKzKK0oEO5_-CBKvYSw4DKY4Wp5UPrrt1ehBFRd79idy7FsUuQ@mail.gmail.com>
Subject: Re: [PATCH] usb: gadget: u_serial: Add null pointer checks after
 RX/TX submission
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>, quic_prashk@quicinc.com, 
	stern@rowland.harvard.edu, linux-usb@vger.kernel.org, 
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
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Hi Greg & Jiri,

>> Or you switch to tty_port refcounting and need not fiddling with this at all
>> ;).
> I agree, Kuen-Han, why not do that instead?

Thanks for the feedback! I agree that switching to tty_port
refcounting is the right approach.

I'm currently digging into tty_port.c to understand the best way to
implement this change. Could you confirm if I'm on the right track by
using tty_kref_get() and tty_kref_put() to address race conditions?
Additionally, do I need to refactor other functions in u_serial.c that
interact with the TTY without refcounting?

Regards,
Kuen-Han