On Sun, Mar 17, 2019 at 10:12 AM Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > > Please see https://github.com/google/syzkaller/blob/master/docs/syzbot.md#bisection > it should answer all of your questions. It does 2 and more. > And in this case it seems to be working as intended bisecting it to a > release tag. No, it's definitely not working as intended. You can see it in the bisect log - you don't actually have a single "git bisect bad" outside of the initial one that you start bisecting with. That's a pretty good sign of bisection being completely broken. Yes, it can happen in theory, but in general with a good bisection, you should see about as many "good" results as "bad". I bet that what's going on is that your initial "let's test every release" uses a _different_ process than the actual bisection itself does. So if I were you, I'd look at what syzbot does differently during bisection vs what it does for that initial "test each release". For example, does it do "make clean" in between each build in one case, but not the other? Does it do "make oldconfig" vs a fixed config generated from scratch every time? Because the fact that you first tested 4.10 bad using the "test each release", and then when you do bisection, the very commit *before* 4.10 is good (the only difference being the EXTRAVERSION and the tag) shows that something went wrong. Linus
