Booting anything after r352057 kills console

I updated my source today and when the computer was booted, the screen
turned black at the point that the drm related kernel modules would
normally load.  Suspecting a drm issue, I commented out the rc.conf line
that loads those kernel modules.  This did not fix my problem.  My last
good kernel was r352057.  I started to bi-sect the svn updates between
today and r352057.  Going backward, all the way to r352064 is not
working.  There were very few changes between r352057 and r352064.  None
of them seem to be console graphics related.  The last entry in my boot
log shows a successful entry of the security policy for ntp.  No logged
messages after this point.

Where do I go from here?  The computer is an Intel i5 Skylake with
onboard graphics.

Tom


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