Re: Kernel 6.5 ttyS1 hang with qemu (was Re: [OE-core] Summary of the remaining 6.5 kernel serial issue (and 6.5 summary)

[Mikko Rapeli <mikko.rapeli@linaro.org>]

Hi,

On Mon, Oct 16, 2023 at 09:35:01AM +0300, Tony Lindgren wrote:
> * Richard Purdie <richard.purdie@linuxfoundation.org> [231015 21:30]:
> > On Sun, 2023-10-15 at 17:31 +0200, Greg Kroah-Hartman wrote:
> > > Can you try the patch below?  I just sent it to Linus and it's from Tony
> > > to resolve some other pm issues with the serial port code.
> > 
> > Thanks for the pointer to this. I've put it through some testing and
> > had one failure so far so I suspect this isn't enough unfortunately.
> >
> > FWIW I was looping the testing on the complete removal of the
> > conditions and didn't see any failures with that.
> 
> Care to clarify what's the failing test now?
> 
> Is the issue still the second port not always coming up after boot or
> something else?

Yes, data from the ttyS1 getty is not coming through from kernel and qemu to
the test framework looking for login prompt after qemu machine boot.
Workarounds like sending "\n\n" from the test framework through qemu to ttyS1
or "echo helloB > /dev/ttyS1" via working ttyS0 don't seem to help and wake
it up.

Cheers,

-Mikko