Boot error SMP

John Baldwin jhb at
Wed Jun 29 18:30:49 GMT 2005

On Wednesday 29 June 2005 01:52 pm, Hans van Leest wrote:
> I got a boot with the new debug kernel, only I got an new instruction
> pointer. this one is:
> 0x8:0xc061a5e7
> When I type db> gdb, it replies that it can't find the backend
> When I type tr after db> I get a lot of data so I want to use serial
> console So I don't have to type it over. Only I get errors
>  From the howto I did this
> cat /etc/ttys
> --snip--
> # The 'dialup' keyword identifies dialin lines to login, fingerd etc.
> ttyd0   "/usr/libexec/getty std.9600"   vt100   on secure
> ttyd1   "/usr/libexec/getty std.9600"   vt100   on secure
> ttyd2   "/usr/libexec/getty std.9600"   vt100   on secure
> ttyd3   "/usr/libexec/getty std.9600"   vt100   on secure

These only let you login over the serial line, you don't need this for the 
kernel console.

> bsd# cat /boot/loader.conf
> set console="comconsole"

This should be all you need.

> I got error like this:
>   bsd init: can't exec getty 'none' for port /dev/console: No such file
> or directory

You must have something weird on the 'console' line in /etc/ttys.  Normally 
the getty on that line should be 'off'.  The way to grab the output is to use 
cut and paste or script(1) or some such on the machine that you are talking 
to the bsd box with, you don't capture the trace info on the bsd machine 
itself.  For example, if you are using some Windows terminal app, you can cut 
and paste the trace info into notepad and then cut and paste that into an 
e-mail.  If you are using another unix box without X11 as the client end of 
the console you could use script(1) to log the output to a file.

That said, having the instruction pointer is good.  To use that, boot the bsd 
box, find the kernel.debug from the kernel you built 
(probably /usr/obj/usr/src/sys/<KERNEL_NAME>/kernel.debug) and run gdb on it 
like so:

# gdb /path/to/kernel.debug

Then, at the gdb> prompt do a list:

gdb> list *0xc061a5e7

John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

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