Re: [PATCH] tty: pl011: Avoid spuriously stuck-off interrupts

Greg KH
2018-04-29T13:18:57Z

On Fri, Apr 27, 2018 at 11:05:44AM +0100, Dave Martin wrote:
> This is an update to a previous RFC [1], to fix a problem observed by
> the qemu community that causes serial input to hang when booting a
> simulated system with data already queued in the UART FIFO [2].
>
> This patch could cause problems for people that are actually relying
> on chars queued in the PL011 RX FIFO during boot or while the UART is
> closed. There are no guarantees about such things working in general.
> In either case, there is no protection against RX FIFO overflow or
> reprogramming of the UART parameters while Linux is not actively
> receiving chars.
>
> Cheers
> ---Dave
>
> [1] [RFC PATCH v4] tty: pl011: Avoid spuriously stuck-off interrupts
> http://lists.infradead.org/pipermail/linux-arm-kernel/2018-April/574033.html
>
> [2] [Qemu-devel] [Qemu-arm] [PATCH] pl011: do not put into fifo
> before enabled the interruption
> https://lists.gnu.org/archive/html/qemu-devel/2018-01/msg06446.html
>
> Dave Martin (1):
> tty: pl011: Avoid spuriously stuck-off interrupts
>
> drivers/tty/serial/amba-pl011.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> --
> 2.1.4

There is no patch here, did something go wrong?

You do not need a "cover letter" for a single patch...

thanks,

greg k-h