[poky] Serial console unusable with poky-image-sdk

[Wolfgang Denk]

Dear Darren Hart,

In message <4D41F2D6.4040406 at linux.intel.com> you wrote:
>
> >> Is there a way to stop dbus-launch from concurring with a login shell
> >> on the serial console port?
> >
> > This patch appears to be working fine for me:
> >
> >> From: Wolfgang Denk<wd at denx.de>
> >> Subject: Stop dbus-launch from interfering with a serial console
> >
> > Signed-off-by: Wolfgang Denk<wd at denx.de>
> > ---
> >
> > diff --git a/meta/recipes-graphics/x11-common/x11-common/etc/X11/Xsession b/meta/recipes-graphics/x11-common/x11-common/etc/X11/Xsession
> > index a87447a..0b73127 100644
> > --- a/meta/recipes-graphics/x11-common/x11-common/etc/X11/Xsession
> > +++ b/meta/recipes-graphics/x11-common/x11-common/etc/X11/Xsession
> > @@ -2,7 +2,7 @@
> >
> >   if [ -x /usr/bin/dbus-launch ]; then
> >       # As this is the X session script, always start a new DBus session.
> > -    eval `dbus-launch --sh-syntax --exit-with-session`
> > +    eval `dbus-launch --sh-syntax --exit-with-session</dev/null`
> >       echo "D-BUS per-session daemon address is: $DBUS_SESSION_BUS_ADDRESS"
> >   fi
> >
> 
> you can also append "console=tty" to the kernel command line and the 
> serial console should work. I've run into this on a couple platforms as 
> well and addressed it this way. This isn't just an X11 issue as I 
> usually boot -minimal images.

I think you misunderstand.  It is not that the serial console port is
not working at all, or that there are any wrong assignments to the
Linux console device.

The problem is that after logging in both the shell and the
dbus-launch processes will read from the same device, and it is pur
chance which of these provesses will read which input character.

The problem is that dbus-launch should not read from the console
terminal at all, and this is what above patch enforces.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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