>Number:         403
>Category:       port-sparc
>Synopsis:       Sparc panics when a bad disk block is encountered
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    gnats-admin (GNATS administrator)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Aug  8 13:05:03 1994
>Originator:     Rolf Grossmann
>Organization:
Technische Universitaet Muenchen
>Release:        NetBSD 1.0_BETA
>Environment:

System: NetBSD flip 1.0_BETA NetBSD 1.0_BETA (TIGKI) #30: Mon Aug 8 20:38:56 MET DST 1994 grossman@flip:/usr/src/sys/arch/sparc/compile/TIGKI sparc


>Description:
	If you try to read a file from the hard disk, that resides on a
	bad sector, the kernel panics with the following messages:
		sd0: sdintr scsi status 0x2 resid 0
		sd0: scsi sense class 7, code 0, key 1, blk 1079344
		sd0: retry 1
		panic: espintr sq
	I could finally track down the problem to sbus/esp.c:espicmd(), where
	sc->sc_hba.hba_busy is incorrectly set to 0. A fix is included below.
	(This might not be the way you'd like to fix this problem, but it
	does what I need. As someone is rewriting the scsi code, this might
	change anyway, but you probably don't want to have a kernel that
	crashes right now ;) )

>How-To-Repeat:
	This might be quite hard, as you probably won't have a disk that
	has a bad block on it. But you can read the code and you'll probaly
	see the problem.
>Fix:
	
*** /usr/src/sys/arch/sparc/sbus/esp.c.orig	Mon Aug  8 19:29:17 1994
--- /usr/src/sys/arch/sparc/sbus/esp.c	Mon Aug  8 19:32:28 1994
***************
*** 1036,1041 ****
--- 1036,1042 ----
  	register volatile struct dmareg *dma = sc->sc_dma;
  	register int r, s, wait;
  	register struct sq *sq;
+ 	register char old_busy;
  
  	/*
  	 * Wait for any ongoing operation to complete.
***************
*** 1045,1050 ****
--- 1046,1052 ----
  		sc->sc_iwant = 1;
  		tsleep((caddr_t)&sc->sc_iwant, PRIBIO, "espicmd", 0);
  	}
+ 	old_busy = sc->sc_hba.hba_busy;
  	sc->sc_hba.hba_busy = 1;
  	splx(s);
  
***************
*** 1117,1123 ****
  		sc->sc_hba.hba_head = sq->sq_forw;
  		(*sq->sq_dgo)(sq->sq_dev, &sc->sc_cdbspace);
  	} else
! 		sc->sc_hba.hba_busy = 0;
  	splx(s);
  	return (r);
  }
--- 1119,1125 ----
  		sc->sc_hba.hba_head = sq->sq_forw;
  		(*sq->sq_dgo)(sq->sq_dev, &sc->sc_cdbspace);
  	} else
! 		sc->sc_hba.hba_busy = old_busy;
  	splx(s);
  	return (r);
  }

>Audit-Trail:
>Unformatted:


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