On Tue, 7 Jul 2015, Masami Hiramatsu wrote: > On 2015/07/07 6:27, Vince Weaver wrote: > > Hello > > > > I've been working on trying to get the perf_fuzzer to start fuzzing the > > PERF_EVENT_IOC_SET_BPF so I've added some really hackish kprobe support. > > > > However before I can get to the BPF testing the kprobe code generates a > > constant stream of WARNINGS which make the machine more or less useless > > until I stop it. I've included a small selection here. > > > > Is this expected? > > Did you get same message without BPF hack? And also, could you tell us > your kernel version and configuration?
It's a Hawell machine running 4.2-rc1. I can post the .config if it's of interest. Well the BPF hack is in the fuzzer, not the kernel. And it's not really a hack, it just turned out to be a huge pain to figure out how to manually create a valid BPF program in conjunction with a valid kprobe event. I did have to sprinkle printks in the kprobe and bpf code to find out where various EINVAL returns were coming from, so potentially this is just a problem of printks happening where they shouldn't. I'll remove those changes and try to reproduce this tomorrow. This is possibly a long standing issue, until now I never ran the fuzzer as root so these particular code paths weren't tested. Vince -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
