Re: ktrace-ing a command that locks up the machine

[christos%astron.com@localhost (Christos Zoulas)]

In article <20201118093741.GB17974%trav.math.uni-bonn.de@localhost>,
Edgar Fuß  <ef%math.uni-bonn.de@localhost> wrote:
>So after fixing kern/53311 and kern/55745 on -8, I'm back to one nesting 
>level down my original task.
>
>I have a command that (when run the second time and with certain USB devices 
>connected) will irrevertibly (to me) partly (no console switching) lock up 
>the machine. I need to enter DDB and reboot.
>
>I would like to ktrace/ktruss the command to see which USB transfer exactly 
>is the one that hangs. However, even with ktrace -s, there is no trace file 
>after the re-boot (on FFS/WAPBL); I can't tell whether it exists before the 
>reboot. Using ktruss, the last trace output to the console is way behind the 
>execution.

ktrace over NFS.

christos