On Tue, Apr 13, 2021 at 07:11:11PM +0200, Dmitry Vyukov wrote: > On Tue, Apr 13, 2021 at 6:57 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Tue, Apr 13, 2021 at 06:47:47PM +0200, Dmitry Vyukov wrote: > > > On Tue, Apr 13, 2021 at 6:13 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > > > Hopefully this patch will make the race a lot more likely to occur. Is > > > > there any way to tell syzkaller to test it, despite the fact that > > > > syzkaller doesn't think it has a reproducer for this issue? > > > > > > If there is no reproducer the only way syzbot can test it is if it's > > > in linux-next under CONFIG_DEBUG_AID_FOR_SYZBOT: > > > http://bit.do/syzbot#no-custom-patches > > > > There _is_ a theoretical reproducer: the test that provoked syzkaller's > > original bug report. But syzkaller doesn't realize that it is (or may > > be) a reproducer. > > > > It ought to be possible to ask syzkaller to run a particular test that > > it has done before, with a patch applied -- and without having to add > > anything to linux-next. > > Yes, this is possible: > http://bit.do/syzbot#syzkaller-reproducers That's not really what I had in mind. I don't want to spend the time and effort installing syskaller on my own system; I want to tell syzbot to run a particular syzkaller program (the one that originally led to this bug report) on a patched kernel. The syzbot instructions say that it can test bugs with reproducers. The problem here is that there doesn't seem to be any way to tell it to use a particular syzkaller program as a reproducer. Alan Stern > The log of tests executed before the crash is available under the > "console output" link: > console output: https://syzkaller.appspot.com/x/log.txt?x=124adbf6d00000 > And this log can be replayed using syz-execprog utility.
