Re: [PATCH v2] tty: resolve loopback wait problem for aging serial port

[Greg KH]

On Wed, Dec 30, 2020 at 08:39:06PM +0800, zhangqiumiao1@xxxxxxxxxx wrote:
> From: Qiumiao Zhang <zhangqiumiao1@xxxxxxxxxx>
> 
> Because serial port is low-speed device, serial port writing will be suspended
> when the buffer of driver layer is full due to serial port aging. The concrete
> representation is n_tty_write blocking in the process of wait_woken, the process
> of writing serial port exists without feedback, and becomes a zombie process.
> So for serial port, set the timeout value of wait_woken function to 60s. Wake up
> and flush the buffer after timeout.
> 
> Signed-off-by: Qiumiao Zhang <zhangqiumiao1@xxxxxxxxxx>
> ---
>  drivers/tty/n_tty.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)

What changed from v1?  Always put that below the --- line as the
documentation asks you to do so.

Please fix up and submit a v3.

thanks,

greg k-h