Subject: Re: kern/32191: integer divide fault trap caused by the ata driver
To: None <kern-bug-people@netbsd.org, gnats-admin@netbsd.org,>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: netbsd-bugs
Date: 11/29/2005 20:19:02
The following reply was made to PR kern/32191; it has been noted by GNATS.

From: Manuel Bouyer <bouyer@antioche.eu.org>
To: gnats-bugs@NetBSD.org
Cc: kern-bug-people@NetBSD.org, gnats-admin@NetBSD.org,
	netbsd-bugs@NetBSD.org
Subject: Re: kern/32191: integer divide fault trap caused by the ata driver
Date: Tue, 29 Nov 2005 21:18:41 +0100

 On Tue, Nov 29, 2005 at 03:02:01PM +0000, matthias.christian@tiscali.de wrote:
 > >Number:         32191
 > >Category:       kern
 > >Synopsis:       integer divide fault trap caused by the ata driver
 > >Confidential:   no
 > >Severity:       serious
 > >Priority:       high
 > >Responsible:    kern-bug-people
 > >State:          open
 > >Class:          sw-bug
 > >Submitter-Id:   net
 > >Arrival-Date:   Tue Nov 29 15:02:00 +0000 2005
 > >Originator:     Matthias-Christian Ott
 > >Release:        netbsd-3
 > >Organization:
 > >Environment:
 > >Description:
 > I get an "integer divide fault trap" caused by the ata driver when booting my computer [0] [1]. See the screenshots for more details.
 > 
 > [0] http://metawire.org/~matthias-christian-ott/pub/netbsd/netbsd-3/integer-divide-fault-trap-0.jpg
 > [1] http://metawire.org/~matthias-christian-ott/pub/netbsd/netbsd-3/integer-divide-fault-trap-1.jpg
 
 Basically wdcprobe1 calls i8254_delay which calls gettick.
 The fault is at gettick+0x1c. From gdb this would be write_eflags(ef).
 I can't see how this can cause a integer divide fault trap.
 
 Even in i8254_delay I can't see how we could get a divide by 0 here.
 
 -- 
 Manuel Bouyer <bouyer@antioche.eu.org>
      NetBSD: 26 ans d'experience feront toujours la difference
 --