Re: [PATCH 0/2] UCSI race condition resulting in wrong port state

Greg Kroah-Hartman
2020-11-06T10:46:44Z

On Wed, Oct 28, 2020 at 10:10:43AM +0100, Greg Kroah-Hartman wrote:
> On Fri, Oct 09, 2020 at 04:40:45PM +0200, Benjamin Berg wrote:
> > From: Benjamin Berg <bberg@redhat.com>
> >
> > Hi all,
> >
> > so, I kept running in an issue where the UCSI port information was saying
> > that power was being delivered (online: 1), while no cable was attached.
> >
> > The core of the problem is that there are scenarios where UCSI change
> > notifications are lost. This happens because querying the changes that
> > happened is done using the GET_CONNECTOR_STATUS command while clearing the
> > bitfield happens from the separate ACK command. Any change in between will
> > be lost.
> >
> > Note that the problem may be almost invisible in the UI as e.g. GNOME will
> > still show the battery as discharging. But some policies like automatic
> > suspend may be applied incorrectly.
> >
> > Cc: Hans de Goede <hdegoede@redhat.com>
> > Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> >
> > Benjamin Berg (2):
> > usb: typec: ucsi: acpi: Always decode connector change information
> > usb: typec: ucsi: Work around PPM losing change information
>
> Do these need to be backported to stable kernel releases? If so, how
> far back?

Due to the lack of response, I guess they don't need to go to any stable
kernel, so will queue them up for 5.11-rc1.

thanks,

greg k-h