[RFC PATCH v3] tty: pl011: Avoid spuriously stuck-off interrupts

[peter.maydell@linaro.org (Peter Maydell)]

On 23 April 2018 at 14:41, Dave Martin <Dave.Martin@arm.com> wrote:
> This is an update to a previous RFC v2 [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].
>
> After discussion, I decided that the approach in [1] was over-
> engineered: it tries to preserve a guarantee that people shouldn't be
> relying on anyway, namely that data sent to the UART prior to kernel
> boot will be received by the kernel; or more generally that data
> received by the UART while the pl011 driver is not opened will be
> received (either intact or at all) by the driver.
>
> If anyone can please test the following and let me know the results,
> that would be much appreciated!
>
>  a) Check that you can still reproduce the bug on mainline without this
>     patch.
>
>  b) Check whether this patch fixes the problem.

Thanks. I'm cc'ing Ciro and Drew, who are the two people I
recall reporting this issue to me.
Link to the patch for their benefit:
 http://lists.infradead.org/pipermail/linux-arm-kernel/2018-April/573120.html

-- PMM