----- On Mar 26, 2018, at 1:55 PM, Alexei Starovoitov [email protected] wrote:
[...]
>
> correct. this set deals with in-kernel tracepoints only.
> No attempt to do anything with tracepoints inside modules.
Please endeavor to handle in-module tracepoints properly, then we'll
be able to pursue a more constructive discussion.
[...]
> Also I hope you noticed that the patch is doing:
> +++ b/include/linux/tracepoint-defs.h
> @@ -33,6 +33,7 @@ struct tracepoint {
> int (*regfunc)(void);
> void (*unregfunc)(void);
> struct tracepoint_func __rcu *funcs;
> + u32 num_args;
> };
>
> To make sure that bpf programs are safe I need to do a static check
> in the verifier that programs don't access arguments beyond
> those specified by the tracepoint.
>
> That was mentioned in the commit log of patch 6 too:
> "
> compute number of arguments passed into tracepoint
> at compile time and store it as part of 'struct tracepoint'.
> The number is necessary to check safety of bpf program access that
> is coming in subsequent patch.
> "
This part of the patch and its associated changelog is fine
with me. Please submit it as a separate commit from the rest
of the tracepoint.{c,h} changes.
[...]
Thanks,
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
