Re: Regression from patch 'tty: hvc: hvc_poll() break hv read loop'

From: Nicholas Piggin
Date: Tue Sep 04 2018 - 17:15:45 EST


On Tue, 4 Sep 2018 11:48:08 -0600
Jason Gunthorpe <jgg@xxxxxxxxxxxx> wrote:

> Hi Nicholas,
>
> I am testing 4.19-rc2 and I see bad behavior with my qemu hvc0
> console..
>
> Running interactive with qemu (qemu-2.11.2-1.fc28) on the console
> providing hvc0, using options like:
>
> -nographic
> -chardev stdio,id=stdio,mux=on,signal=off
> -mon chardev=stdio
> -device isa-serial,chardev=stdio
> -device virtio-serial-pci
> -device virtconsole,chardev=stdio
>
> I see the hvc0 console hang regularly, ie doing something like 'up
> arrow' in bash causes the hvc0 console to hang. Prior kernels worked
> OK.
>
> Any ideas? I'm not familiar with this code.. Thanks!

Yes I have had another report, I'm working on a fix. Sorry it has taken
a while and thank you for the report.

Thanks,
Nick