Re: [PATCH] Revert "console: don't prefer first registered if DT specifies stdout-path"

From: Greg Kroah-Hartman
Date: Thu Nov 10 2016 - 09:14:34 EST


On Tue, Nov 08, 2016 at 08:00:32AM +0100, Greg Kroah-Hartman wrote:
> On Tue, Nov 08, 2016 at 11:46:35AM +1100, Michael Ellerman wrote:
> > Hans de Goede <hdegoede@xxxxxxxxxx> writes:
> >
> > > This reverts commit 05fd007e4629 ("console: don't prefer first registered
> > > if DT specifies stdout-path").
> > >
> > > The reverted commit changes existing behavior on which many ARM boards
> > > rely. Many ARM small-board-computers, like e.g. the Raspberry Pi have
> > > both a video output and a serial console. Depending on whether the user
> > > is using the device as a more regular computer; or as a headless device
> > > we need to have the console on either one or the other.
> > >
> > > Many users rely on the kernel behavior of the console being present on
> > > both outputs, before the reverted commit the console setup with no
> > > console= kernel arguments on an ARM board which sets stdout-path in dt
> > > would look like this:
> > >
> > > [root@localhost ~]# cat /proc/consoles
> > > ttyS0 -W- (EC p a) 4:64
> > > tty0 -WU (E p ) 4:1
> > >
> > > Where as after the reverted commit, it looks like this:
> > >
> > > [root@localhost ~]# cat /proc/consoles
> > > ttyS0 -W- (EC p a) 4:64
> > >
> > > This commit reverts commit 05fd007e4629 ("console: don't prefer first
> > > registered if DT specifies stdout-path") restoring the original behavior.
> > >
> > > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> >
> > This is also breaking various powerpc systems.
> >
> > Linus can you please merge this revert for 4.9 ?
>
> I'll queue it up with other tty changes for 4.9-final.

Oops, wait, it's going through Andrew's tree, nevermind...