From: greg@kroah.com (Greg KH)
Date: Sun, 29 Apr 2018 15:18:57 +0200
Subject: [PATCH] tty: pl011: Avoid spuriously stuck-off interrupts
In-Reply-To: <1524823545-11309-1-git-send-email-Dave.Martin@arm.com>
References: <1524823545-11309-1-git-send-email-Dave.Martin@arm.com>
Message-ID: <20180429131857.GC23018@kroah.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

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