Re: [PATCH tty-next v5 5/6] serial: 8250: Switch to nbcon console

[Jon Hunter]

Hi John,

On 08/10/2025 16:56, John Ogness wrote:
> Hi Jon,
>
> On 2025-01-15, Jon Hunter <jonathanh@xxxxxxxxxx> wrote:
> > I have noticed a suspend regression on -next for some of our 32-bit
> > Tegra (ARM) devices (Tegra20, Tegra30 and Tegra124). Bisect is pointing
> > to this commit and reverting this on top of -next (along with reverting
> > "serial: 8250: Revert "drop lockdep annotation from
> > serial8250_clear_IER()") fixes the issue. So far I have not dug in any
> > further. Unfortunately, I don't have any logs to see if there is some
> > crash or something happening but I will see if there is any more info I
> > can get.
>
> I have been looking into reproducing this using other 8250/ARM boards
> (BeagleBone Black and Phytec WEGA). Unfortunately it is just showing me
> all kinds of other brokenness (in mainline) and essentially making it
> impossible to confirm that I am seeing what you are seeing, since
> suspend/resume is randomly dying without my 8250-nbcon patch.
>
> Before I start spending weeks investigating/fixing most likely totally
> unrelated PM or BSP issues, is it possible that I could receive one of
> the boards you mentioned so that I can reproduce and debug the actual
> problem you are reporting? If this is possible, feel free to take this
> conversation offline so that we can discuss delivery details. Thanks!

These boards are really old now and so I don't really have any that we 
can ship. It would be great to get this change merged as I see that it 
is needed for RT support. I could see if I can resurrect a Tegra124 
Jetson TK1 and test again on that to see if we can get some logs.

Thierry, do you have a Tegra124 Jetson TK1 handy to test this change on?

Jon

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nvpublic