no match while resolving probe point kernel.function("printk")

[Frank Ch. Eigler]

Om <om.turyx@gmail.com> writes:

> I am trying to execute this script.
> [...]
> # stap -v -u printk-time-toggle.stp  1
> [...]
> semantic error: write to target variable not permitted: identifier
> '$printk_time' at printk-time-toggle.stp:8:4
> [...]

That's the key message there.  Since this script attempts to modify
a kernel variable, it needs to be run under guru mode ("stap -g ...").

> When I comment out the statement $printk_time = 1 - $printk_time, it
> compiles without complaining any semantic error. [...]

Right, because then the script does not attempt anything privileged.


- FChE