no output to serial console from /init process on ml405

[Wolfgang Reissnegger]

The thing that points to a problem with init is:
  Kernel panic - not syncing: Attempted to kill init!

What is the string that is supposed to be printed? Maybe the printf
tries to print a string at an invalid address, causing init to crash?

Also, you can check if you set the option for console on serial output:
  Location:
    -> Device Drivers
      -> Character devices
        -> Serial drivers
          -> 8250/16550 and compatible serial support (SERIAL_8250 [=y])

Cheers,
   Wolfgang

Anton Kowalski wrote:
> Wolfgang,
> 
> Thanks, I'll try your suggestion.
> 
> It's worth noting that the init executable is calling into the
> kernel.
> 
> I put a printk in sys_write, which is on the call path of printf()
> and the output is sent to the console. However, the output of printf
> is not to be seen. This suggests the problem is perhaps in the serial
>  device setup?
> 
> Anton
> 
> On 8/8/07, Wolfgang Reissnegger <wolfgang.reissnegger at xilinx.com>
> wrote:
>> Hi Anton,
>> 
>> it looks as if your init executable is not doing the right thing
>> and for some reason terminates. Maybe your inittab configuration is
>> wrong? Maybe the init executable has been compiled with the wrong
>> options?
>> 
>> You can try to copy another executable (e.g. sh, getty) into /init
>> and see if you get any output. If you see anything doing that then
>> most likely there's something wrong with your init executable.
>> 
>> Wolfgang
>> 
>> Anton Kowalski wrote:
>>> Hi All:
>>> 
>>> I'm trying to bring up linux 2.6.21.1 on an ml405 board. The
>>> kernel boots fine but the init process does not produce any
>>> output. The /init program resides in an initramfs file system and
>>> I believe the /dev device files have been set up correctly.
>>> Here's an excerpt from my initramfs specification:
>>> 
>>> dir /dev 755 0 0 nod /dev/console 644 0 0 c 5 1 nod /dev/ttyS0
>>> 644 0 0 c 4 64
>>> 
>>> (I am able to open these files from the init program. I tested
>>> this by sleeping for a specified time on success.)
>>> 
>>> Also, printk continues to function after /init terminates and
>>> before the kernel panics.
>>> 
>>> Here are the last few lines of the console output:
>>> 
>>> [    0.507478] Serial: 8250/16550 driver $Revision: 1.90 $ 4
>>> ports, IRQ sharing disabled [    0.513862] serial8250.0: ttyS0 at
>>> MMIO 0x80201003 (irq = 3) is a 16550A [    2.927509] RAMDISK
>>> driver initialized: 1 RAM disks of 8192K size 1024 blocksize [
>>> 3.018391] tun: Universal TUN/TAP device driver, 1.6 [
>>> 3.079115] tun: (C) 1999-2004 Max Krasnyansky <maxk at qualcomm.com> 
>>> [    3.154919] mice: PS/2 mouse device common for all mice [
>>> 3.218021] TCP cubic registered [    3.257034] NET: Registered
>>> protocol family 1 [    3.309405] NET: Registered protocol family
>>> 17 [    3.363462] Freeing unused kernel memory: 300k init [
>>> 23.488277] Kernel panic - not syncing: Attempted to kill init! [
>>> 23.559517] Rebooting in 180 seconds..<NULL>
>>> 
>>> I'm using the plb uart and the 8250.c driver. (The obp uartlite
>>> driver didn't work so I switched.) The kernel and the init
>>> program were compiled with eldk.
>>> 
>>> Any insights into resolving this problem are greatly appreciated.
>>> 
>>> 
>>> 
>>> Anton _______________________________________________ 
>>> Linuxppc-embedded mailing list Linuxppc-embedded at ozlabs.org 
>>> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
>>> 
>> 
>