Re: I/O page faults from 8250_mid PCIe UART after TIOCVHANGUP

From: Ilpo Järvinen
Date: Mon Sep 19 2022 - 10:12:42 EST


On Mon, 19 Sep 2022, Andy Shevchenko wrote:

> On Thu, Sep 15, 2022 at 07:27:45PM +0300, Ilpo Järvinen wrote:
> > On Wed, 14 Sep 2022, Andy Shevchenko wrote:
> > > On Wed, Sep 14, 2022 at 02:10:44PM +0300, Lennert Buytenhek wrote:
> > > > On Wed, Sep 14, 2022 at 01:09:40PM +0300, Andy Shevchenko wrote:
>
> ...
>
> > - /*
> > - * The above check will only give an accurate result the first time
> > - * the port is opened so this value needs to be preserved.
> > - */
>
> Side note: I haven't got why you removed this comment (it may be some staled
> info, but shouldn't be done in the separate change then?).

I cleaned up this part in v2 (as you probably noticed). I was just an
artifact of how the fix got initially made.

I've also located the place where the comment belongs to. "The above
check" refers to the THRE test. However, I don't fully understand the
comment itself, that is, why the test is claimed to only work for for the
first time. As long as FIFO is cleared beforehand, I think it should work
on other times too.


--
i.