Re: CVS commit: src/sys [freeze on boot]

[Andrew Doran <ad%netbsd.org@localhost>]

On Mon, Jan 20, 2020 at 09:28:32AM -0800, Paul Goyette wrote:

> On Mon, 20 Jan 2020, Patrick Welche wrote:
> 
> > On Mon, Jan 20, 2020 at 12:51:00PM +0000, Andrew Doran wrote:
> > > This also happened the last time I touched rw_downgrade(), and I backed out
> > > the change then, but both times I don't see the bug.  I have some questions:
> > > 
> > > - Are you running DIAGNOSTIC and/or LOCKDEBUG?  I would be very interested
> > >   to see what happens with a LOCKDEBUG kernel here.
> 
> Hmmm, at least on x86, in the LOCKDEBUG case we don't use the assembler
> stubs;  we simply use the C versions.
> 
> On IRC/ICB, mlelstv has indicated there's something wrong in the stubs,
> but I don't see it.

Yup, I think it's the stubs choking on the RW_NODEBUG flag being set. 
Testing a change for that now.

Andrew

> 
> > One worked with the addition of LOCKDEBUG. The other didn't, but it seems
> > to be unrelated:
> 
> Yeah, that backtrace looks unrelated.
> 
> 
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