On Tue, Apr 02, 2019 at 04:37:19PM +0200, Daniel Borkmann wrote:
> On 04/02/2019 01:58 PM, Paul Chaignon wrote:
> > Three checks for verifier bugs were introduced in commit f4d7e40 ("bpf:
> > introduce function calls (verification)"). The bugs were reported as
> > incorrect programs instead of kernel warnings as the present patch
> > implements.
> >
> > Signed-off-by: Paul Chaignon <[email protected]>
>
> Thanks for the patch, I think these WARN_ONCE() are a bit out of context
> though,
> meaning it lacks additional information about the program in kernel log once
> we
> actually manage to trigger it which we'd otherwise would potentially have had
> with
> the verbose() log. And from a program debugging pov, it makes it harder after
> this
> patch when verification log would suggest that all is fine. Looks like we
> already
> have a few WARN_ONCE() in verifier, they should probably be converted to
> verbose()
> as well to be consistent. If we really want to have a kernel warn, then lets
> add a
> helper macro verbose_and_warn(...) which will trigger a one-time warning, but
> keeps
> the verbose log intact as well.
I think they should stay as verbose() messages and some of the WARN_ON
should be converted to verbose().
I don't think there is a need for verbose_and_warn().
