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Date: Tue, 27 May 1997 14:12:56 +0100 (BST)
From: Doug Rabson <dfr@nlsystems.com>
To: Bob Bishop <rb@gid.co.uk>
cc: Karl Denninger <karl@Mcs.Net>, current@freebsd.org
Subject: Re: Boom! :-)
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On Tue, 27 May 1997, Bob Bishop wrote:

> At 0:24 +0100 27/5/97, Karl Denninger wrote:
> >On Mon, May 26, 1997 at 07:58:28PM +0100, Bob Bishop wrote:
> >>[...]
> >> If, as I suspect, 0x8:0xf01119b0 = _lockstatus + 0x8, this is a
> >> particularly bad case of kern/3581.
> >>[...]
> >Hmmm... Don't think so... this looks to be in lockinit...
> 
> Sure does. Congratulations! Looks like you've found another semi-repeatable
> way to summon up the lock gremlins! :-) :-) :-{
> 
> Seriously folks, the size of this club (people who regularly fall down
> various lock-related holes) seems to be growing. I have a little time to
> spare at the moment but I'm not up to speed with this stuff, and I have to
> say it looks unpleasant.

This is a workaround for the lockstatus panic.  A better fix will probably
have to wait until Peter is finished with poll(2).

Index: ufs_vnops.c
===================================================================
RCS file: /home/ncvs/src/sys/ufs/ufs/ufs_vnops.c,v
retrieving revision 1.50
diff -u -r1.50 ufs_vnops.c
--- ufs_vnops.c	1997/05/17 18:32:53	1.50
+++ ufs_vnops.c	1997/05/27 13:11:19
@@ -1788,6 +1788,9 @@
 	} */ *ap;
 {
 
+	if (ap->a_vp->v_flag & VXLOCK)
+		return TRUE;
+
 	return (lockstatus(&VTOI(ap->a_vp)->i_lock));
 }
 


--
Doug Rabson				Mail:  dfr@nlsystems.com
Nonlinear Systems Ltd.			Phone: +44 181 951 1891
					Fax:   +44 181 381 1039