kprobes problem

[Baruch Even]

Baruch Even wrote:
> I've got a jprobe working on the entry of the function and wanted a 
> kprobe at the end of the function, on the ret instruction.
> 
> I've extracted with a script the offset of the ret instruction but when 
> hitting the probe the kernel oopses.
> 
> If I move the trap a few instructions earlier to a point where there is 
> an instruction with more than one byte[1], everything works. I can do 
> that but I can't really automate it as I wanted.

If I move the kprobe one byte before the ret (on an instruction 
boundary) it still works, so it's not just that I'm on a single byte 
instruction.

Baruch