__rw_wlock_hard panic on 1st malloc

[Andrew Turner]

On Wed, 17 Apr 2013 22:36:29 -0600
Warner Losh <imp at bsdimp.com> wrote:

> 
> On Apr 17, 2013, at 7:36 PM, Andrew Turner wrote:
> 
> > On Wed, 17 Apr 2013 09:37:26 -0600
> > Warner Losh <imp at bsdimp.com> wrote:
> > 
> >> I don't think it is, at least not with clang compiled code. Ian was
> >> saying on IRC that he saw this and went back to gcc and life was
> >> good.
> > 
> > I suspect it is an issue with the newer version of clang imported
> > recently. I have tested with an old version of clang and an updated
> > kernel and had no issues booting.
> 
> If I take WITNESS out of the kernel, I have no issues either. Not
> sure what WITNESS' problem is...

I've tried with an updated clang on a PandaBoard with WITNESS enabled.
The only issue I'm hitting is vm_thread_new fails, but this is after
FreeBSD enters userland which, from you other emails, appears to be
further than you are getting.

I have set unmapped_buf_allowed = 0 in sys/arm/arm/pmap-v6.c to work
around the above stack issue. I don't know if this will fix the issue
or not but you can try it to see.

Andrew