Ed Schouten ed at
Tue Aug 25 07:31:00 UTC 2009

* Marcel Moolenaar <xcllnt at> wrote:
> I would approach the problem differently: decouple printf() in the
> kernel from anything to which we have a TTY attached. Instead, look
> at printf() as a means to write to the message buffer only. Echoing
> things that go into the message buffer to the console becomes 1)
> optional (yay!), and 2) something you can do by going through the TTY
> layer (use a kthread or use a process [syslog]).

Yeah. That would be a lot better, but that means you still need to have
a lot of code to make it work properly w.r.t. kernel panics:

- When you're in the kernel debugger, you still need to have this
  synchronous programming interface to print data and read keyboard
- In this context, you need to add extra code to flush the buffer before

I think we could look at this approach somewhere in the future, but
better not now. I'd rather not debug debugging interfaces. ;-)

 Ed Schouten <ed at>
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