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

Dave Martin
2018-04-30T12:49:19Z

On Sun, Apr 29, 2018 at 03:18:57PM +0200, Greg KH wrote:
> 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...

I wanted to provide some additional context for the benefit of people
who'd been reviewing earler RFCs for this change, though I could have
put it under the tearoff instead.

I was expecting --cover-letter to generate [PATCH 0/1] and [PATCH 1/1]
Subject lines, but it seems that it doesn't do that.

To clarify, there is only intended to be one patch here.

Do you want me to repost?

Cheers
---Dave