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

[Greg Kroah-Hartman]

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.

thanks,

greg k-h