Rune Torgersen wrote:

Scott Wood wrote:

quoted

You're recursively entering lock_timer_base, which does a
spin_lock_irqsave().  Either interrupts are enabled when they should
not be, or an interrupt was supposed to be threaded that isn't.

Sort of figured. How do I figure out which one, and how to fix it?

Almost certainly the latter.  Is the disk interrupt shared with any 
other interrupts, that are marked IRQF_NODELAY?  The -rt patch doesn't 
seem to handle mixing the two well.

Oh, and just to be sure: you do have CONFIG_PREEMPT_RT turned on, and 
not just CONFIG_PREEMPT, right?  The non-preempt-rt versions in the -rt 
patch don't look like they disable interrupts, though I may just be 
getting lost in a sea of underscores and ifdefs.

-Scott