printk, klogd

Albert Cahalan (albert@ccs.neu.edu)
Wed, 28 Jun 1995 20:49:52 -0400


> > BTW, I have some ideas about the register dump feature. Since it is
> > explicitly requested by the user, why not always print it on the console
> > (like all the Oops messages) even if klogd is running? If something bad
> > happened, it may be difficult to log in and kill klogd...

> I have been coding support into klogd for converting numeric kernel
> addresses into symbolic values. This was prompted by some suggestions
> earlier in this group that this would be a helpful feature to have.
>
> The problem with all these issues is that when the kernel is pooping
> out from underneath you there is probably no REALLY good place to
> dump output.

Stop the interrupts and write directly to video memory, all printer
ports, all serial ports, and the first sector in the floppy drive.
You can then send the oops message (not all the numbers) out the PC
speaker via morse code. If you can return to real mode or CRC check
the disk drivers, write to the diagnostic cylinder of the hard drive.