[hpoj-devel] SMP lockup

[Dr. J. W. G. <dr...@dr...>]

I have seen old reports of SMP issues but nothing recently, so for the 
record for a PSC 750 running WhiteBox Linux (kernel 
2.4.21-15.0.4.ELsmp) on a SMP machine, after a tarball install of  
hpoj-0.91 I find that the computer locks up (i.e. frozen screen, no 
response to keyboard/mouse, requires hitting "reset" button to re-boot) 
when I try to use xsane.  If I boot in non-SMP mode then xsane works 
normally.

I was hoping that I could just re-boot into non-SMP modes when I  need 
to scan, but find that with pt-al active in SMP my machine locks up in 
the middle of the night!  Apparently this is related to the following 
messages I found in /var/log/messages (but don't understand):
   04:02:03 localhost kernel: printer.c: usblp0: nonzero read/write bulk 
status received: -2
   04:02:03 localhost kernel: printer.c: usblp0: error -2 reading from 
printer

So I've had to remove start-up of pt-al at boot time (i.e. from 
/etc/init.d) and the middle-of-the-night lock-ups then cease.  I assume 
that if I need to use the scanner I can reboot into non_SMP mode and 
then start pt-al manually but have not tried this (after wasting 7 
hours of my life trying to get things working, I reached my frustration 
limit.)

Printing works find throughout all this in SMP and non-SMP, which I 
believe occurs through CUPS, which  is started prior to pt-al in the 
boot sequence.

-- 
Dr. John W. (Jack) Glendening   Meteorologist