Re: INFO: trying to register non-static key in is_dynamic_key

From: Greg KH
Date: Fri Jun 19 2020 - 04:31:14 EST


On Fri, Jun 19, 2020 at 09:35:30AM +0200, Dmitry Vyukov wrote:
> On Fri, Jun 19, 2020 at 9:07 AM Greg KH <greg@xxxxxxxxx> wrote:
> >
> > On Thu, Jun 18, 2020 at 02:17:15PM -0700, syzbot wrote:
> > > Hello,
> > >
> > > syzbot found the following crash on:
> > >
> > > HEAD commit: b791d1bd Merge tag 'locking-kcsan-2020-06-11' of git://git..
> > > git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=13f305a9100000
> > > kernel config: https://syzkaller.appspot.com/x/.config?x=16c2467d4b6dbee2
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=42bc0d31b9a21faebdf8
> > > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=136ad566100000
> > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10138f7a100000
> > >
> > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > Reported-by: syzbot+42bc0d31b9a21faebdf8@xxxxxxxxxxxxxxxxxxxxxxxxx
> > >
> > > INFO: trying to register non-static key.
> > > the code is fine but needs lockdep annotation.
> >
> > Why is INFO: triggering syzbot?
>
> This is a kernel bug, no?
>
> And there are lots of other kernel bug types that start with INFO:
> https://github.com/google/syzkaller/blob/master/pkg/report/linux.go#L1302
>
> The rules to understand when linux kernel has bugged are insanely
> complex in syzkaller:
> https://github.com/google/syzkaller/blob/master/pkg/report/linux.go#L914-L1685
> (+hundreds of hardcoded function names and file names above).

I understand it's tough, but "the code is fine but needs lockdep
annotation" feels like it's a "here's an improvement that you can make"
type of report, not a "crash" like this message says.

thanks,

greg k-h