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 <paul.chaignon@xxxxxxxxxx> > > 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().