Hi Song, On Thu, Feb 17, 2022 at 9:05 PM Song Liu <songliubraving@xxxxxx> wrote: > > Hi Aleksandr, > > > On Feb 17, 2022, at 10:32 AM, Aleksandr Nogikh <nogikh@xxxxxxxxxx> wrote: > > > > Hi Song, > > > > On Wed, Feb 16, 2022 at 5:27 PM Song Liu <song@xxxxxxxxxx> wrote: > >> > >> Hi Aleksandr, > >> > >> Thanks for your kind reply! > >> > >> On Wed, Feb 16, 2022 at 1:38 AM Aleksandr Nogikh <nogikh@xxxxxxxxxx> wrote: > >>> > >>> Hi Song, > >>> > >>> Is syzkaller not doing something you expect it to do with this config? > >> > >> I fixed sshkey in the config, and added a suppression for hsr_node_get_first. > >> However, I haven't got a repro overnight. > > > > Oh, that's unfortunately not a very reliable thing. The bug has so far > > happened only once on syzbot, so it must be pretty rare. Maybe you'll > > have more luck with your local setup :) > > > > You can try to run syz-repro on the log file that is available on the > > syzbot dashboard: > > https://github.com/google/syzkaller/blob/master/tools/syz-repro/repro.go > > Syzbot has already done it and apparently failed to succeed, but this > > is also somewhat probabilistic, especially when the bug is due to some > > rare race condition. So trying it several times might help. > > > > Also you might want to hack your local syzkaller copy a bit: > > https://github.com/google/syzkaller/blob/master/syz-manager/manager.go#L804 > > Here you can drop the limit on the maximum number of repro attempts > > and make needLocalRepro only return true if crash.Title matches the > > title of this particular bug. With this change your local syzkaller > > instance won't waste time reproducing other bugs. > > > > There's also a way to focus syzkaller on some specific kernel > > functions/source files: > > https://github.com/google/syzkaller/blob/master/pkg/mgrconfig/config.go#L125 > > Thanks for these tips! > > After fixing some other things. I was able to reproduce one of the three > failures modes overnight and some related issues from fault injection. > These errors gave me clue to fix the bug (or at least one of the bugs). > > I have a suggestions on the bug dashboard, like: > > https://syzkaller.appspot.com/bug?id=86fa0212fb895a0d41fd1f1eecbeaee67191a4c9 > > It isn't obvious to me which image was used in the test. Maybe we can add > a link to the image or instructions to build the image? In this case, I > think the bug only triggers on some images, so testing with the exact image > is important. Hmm, that's interesting. If the exact image can really make a difference, I think we could e.g. remember the images syzbot used for the last 1-2 months and make them downloadable from the bug details page. I'll check if there are any obstacles, at first sight this should not be a problem. Thanks for the suggestion! -- Best Regards, Aleksandr > > Thanks again, > Song
