Interesting, yet stupid test case

[Mark Johnston]

On Fri, Aug 23, 2013 at 09:59:43AM -0700, Sean Bruno wrote:
> On Mon, 2013-08-19 at 14:54 -0400, Mark Johnston wrote:
> > On Mon, Aug 19, 2013 at 10:44:54AM -0700, Sean Bruno wrote:
> > > Was able to get mfi to detonate (via CAM) today on stable/9 
> > > 
> > > At the loader prompt, physically remove some amount of drives (in my
> > > case drives 0-5, as 6-11 are my zroot).  Boot up into single user via
> > > boot -s
> > > 
> > > System will attempt to process all the events in the controller on boot
> > > up and die violently.  :-)
> > 
> > Yuck. :(
> > 
> > I think we're not supposed to drop the SIM lock before calling
> > xpt_rescan(); the other drivers I've looked at don't do this at least.
> > We're also unnecessarily dropping the mfi lock around the call to
> > xpt_alloc_ccb_nowait().
> > 
> > I think the following (untested) patch should help. I can try testing it
> > myself later if I can get a hold of some equipment at work (might take a
> > few days).
> > 
> > Thanks,
> > -Mark
> > 
> Yup, this fixes the panic on startup on a Dell H310 if I pull 3 disks
> out at the loader prompt and then continue to boot.

Thanks! I've tested it on FreeBSD 8 with a 9261-8i controller, works for
me too. I'll commit it soon.

-Mark