kernel trap 12 with interrupts disabled

[Alastair Hogge]

On Sat, 4 Mar 2017 10:34:39 PM Chris H wrote:
> On Sun, 05 Mar 2017 14:26:31 +0800 Alastair Hogge <agh at fastmail.fm> wrote
> 
> > On Sat, 4 Mar 2017 10:08:45 PM Chris H wrote:
> > > Thanks for the reply.
> > > I rebooted to kernel.old, so I could get the exact
> > > src revision I built this on. It's r314640
> > > 
> > > Any news as to whether it's safe to update src, and
> > > build a usable kernel?
> > 
> > I am not able to boot a kernel > r314627.  I currently have a r314627
> > kernel running with a r314687 world.
> 
> Looking at the output in my trap; I got the impression that
> the commit: r314636, might be to blame --

[removed commit log]

Thanks for the correct.

> I'm thinking to back that commit out, and giving world/kernel
> another shot.

I changed ${src}/sys/x86/x86/mca.c to return immediately:

--- sys/x86/x86/mca.c   (revision 314698)
+++ sys/x86/x86/mca.c   (working copy)
@@ -1016,6 +1016,7 @@
 static void
 _mca_init(int boot)
 {
+return;
        uint64_t mcg_cap;
        uint64_t ctl, mask;
        int i, skip;

I have a working & sync'd kernel + world.