Re: db4ead2cd5 ("Default enable RCU list lockdep debugging with .."): WARNING: suspicious RCU usage

From: Paul E. McKenney
Date: Mon Apr 06 2020 - 11:32:39 EST


On Mon, Apr 06, 2020 at 11:22:59AM -0400, Joel Fernandes wrote:
> On Mon, Apr 06, 2020 at 08:20:57AM +0530, Madhuparna Bhowmik wrote:
> > On Sun, Apr 05, 2020 at 07:52:32AM -0700, Paul E. McKenney wrote:
> > > On Sun, Apr 05, 2020 at 06:10:31PM +0800, kernel test robot wrote:
> > > > Greetings,
> > > >
> > > > 0day kernel testing robot got the below dmesg and the first bad commit is
> > > >
> > > > https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2020.03.21a
> > >
> > > Is some of the required conversion still left to be done? Or on its
> > > way up some other tree?
> > >
> > > If either of these two, my normal approach would be to hold this commit
> > > back in order to give the fixes time to hit mainline.
> > >
> > > But either way, please let me know!
> > >
> > Yes, some of the patches are not yet reviewed by maintainers and we will
> > resend them. Also, this report reports a few new ones that we haven't
> > fixed yet (need some help from maintainers to do so).
> > We are working on fixing them. May be holding the commit is a
> > good idea.
>
> I am Ok with holding on to the commit for mainline. But I would like it into
> linux-next so that we and others can get some more velocity on fixing the
> remaining issues (and any maintainers who have not yet accepted patches to
> review those). We fixed most of them but there could be some more lurking.
> Paul, how does that sound?

Once v5.7-rc1 comes out, it sounds great!

(Just got my knuckles rapped (gently) for forgetting to pull this stuff
out of -next for all of last week.)

So early next week it returns to -next.

Thanx, Paul

> Either way, we should consider that this feature is turned on only for
> lockdep-enabled kernels so it is only used for debugging.
>
> thanks,
>
> - Joel
>