>Number:         97
>Category:       kern
>Synopsis:       sbintr calls through NULL on stray intr
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    gnats-admin (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 24 22:05:03 1994
>Originator:     Bill Sommerfeld
>Organization:
	None
>Release:        -current
>Environment:
    	
System: NetBSD orchard.medford.ma.us 0.9a ORCHARD#7 i386


>Description:
	the soundblaster driver, /sys/arch/i386/isa/sb.c, in sbintr(),
	calls through the dma completion routine (sc->sc_intr) function
	pointer without checking first to see if it's NULL.
	My system occasionally generates stray interrupts on IRQ 7, which
	is the IRQ that the soundblaster is on..
	
>How-To-Repeat:
	happens under load occasionally; seems to be related to using multiple
	serial lines at once.
>Fix:
(untested as of yet).	
*** 1.1	1994/01/25 05:26:04
--- sb.c	1994/01/25 05:27:08
***************
*** 622,630 ****
  	if (sc->sc_mintr != 0) {
  		int c = rdsp(sc->sc_base);
  		(*sc->sc_mintr)(sc->sc_arg, c);
! 	} else
  		(*sc->sc_intr)(sc->sc_arg);
! 
  	return (1);
  }
  
--- 622,630 ----
  	if (sc->sc_mintr != 0) {
  		int c = rdsp(sc->sc_base);
  		(*sc->sc_mintr)(sc->sc_arg, c);
! 	} else if (sc->sc_intr != 0) {
  		(*sc->sc_intr)(sc->sc_arg);
! 	}
  	return (1);
  }
  
>Audit-Trail:
>Unformatted:

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