[Clfs-support] Cannot login on serial port (embedded ARM, busybox)

[Andrew Bradford]

On Mon, Oct 10, 2011 at 1:25 AM, Lance Jump <lancej29 at gmail.com> wrote:
>
> I cannot login into the embedded system to work. I am using the serial port
> for login. When the system boots, I get a login prompt to which I enter the
> user (root -- there is currently no password for root). The system reports:
>
> Jan 1 12:53:27 login[595]: root login on 'ttyS0'
>
> But then immediately returns to the login prompt.

Is /dev/ttyS0 really the serial port you should be using?  Check your
bootloader (most likely uboot) to see what arguments it is passing to
the kernel regarding console settings.  A first guess is that the
BusyBox init is outputting its output to where ever the kernel was
told to but then when you log in, it's doing so on ttyS0.

> Here is the output near
> the end of the boot and after I try to log inL

Can you provide the entire boot output including uboot output data?
http://pastebin.cross-lfs.org/

> I have built the system using CLFS Embedded GIT-0.0.1-20110514. I am
> building in a chroot environment of LFS live 6.3 inside a Ubuntu 10.04 32bit
> x86 bit host. The embedded system is ARM (Marvell Kirkwood OpenRD Client).

Any reason for building inside the chroot?  Building directly on
Ubuntu 10.04 and following the directions in the embedded book should
lead you to a properly built system.  I'm not at home now but I
believe I've built CLFS successfully in Ubuntu 10.04 (but yes, that
was inside a chroot on a Debian 6 system :)

> Using a /bin/mount command in place of the getty command, I have found that
> fstab files have not mounted (including /proc, /sys, /dev/pts).  This is
> supposed to be done by the startup script, but I don't think it is executing
> since messages from it do not appear (including ones that I log to
> /var/log).  If I replace the "::sysinit:/etc/rc.d/startup" with
> "::sysinit:/bin/busybox mount -a" then the file systems are mounted (but I
> still can't log in).

Are your bootscripts all in the proper places?
The "startup" script should be mounting most of the required filesystems.
See https://gist.github.com/874183 for an example CLFS boot on a
BeagleBoard-xM.  The only difference between that boot and yours
should be the GCC flags (which I think you probably have correct if
you're getting any kind of boot) and kernel configuration (and my boot
uses slightly older versions of software since it was from March
2011).

-Andrew