Ron Heiby (The Moderator) <unix-request@cbosgd.UUCP> (03/13/85)
Unix Technical Digest Wed, 13 Feb 85 Volume 1 : Issue 14
Today's Topics:
Panic: munhash (2 msgs)
Panic: munhash (and bugs in general)
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Date: 11 Feb 85 17:53:21 GMT
From: system@asuvax.UUCP (Marc Lesure)
Subject: Panic: munhash
I need an explanation of what "Panic: munhash" means. We are running
4.2bsd and seem to crash daily with this panic. Also, is there any
sort of documentation which explains what the different panics are
and what they mean.
---
Marc Lesure, System Manager, Engineering Computer Center
Arizona State University, Tempe, Arizona
UUCP: ...!ucbvax!arizona!asuvax!lesure
CSNET: lesure@asu
------------------------------
Date: 12 Feb 85 17:48:30 GMT
From: rick@seismo.UUCP (Rick Adams)
Subject: Panic: munhash
>From mccallum@opus.ARPA Wed Dec 21 15:14:15 1983
Date: 20 Dec 83 6:38:33-PST (Tue)
Subject: Re: panic: munhash (4.2BSD crash)
The bug fix for the panic: munhash in 4.2/4.1c has been posted.
The posted fix did not explain under what conditions the panic occurs.
The problem shows up when you have a LARGE file system and use a debugger
on program that resides in the part of the file system that makes the block
number field use all 20 bits. The fix is as follows:
From: RWS%mit-xx@sri-unix.UUCP
Subject: sundry 4.2 bugs
Message-ID: <13280@sri-arpa.UUCP>
Date: Wed, 2-Nov-83 15:15:00 MST
Lines: 64
Despite claims to the contrary, the block number sign extension problem still
exists. Berkeley put in a fix that should have worked, but a C compiler bug
apparently keeps it from working. In /sys/sys/vm_mem.c in memall() the code
swapdev : mount[c->c_mdev].m_dev, (daddr_t)(u_long)c->c_blkno
should be changed to
swapdev : mount[c->c_mdev].m_dev, c->c_blkno
and in /sys/vax/vm_machdep.c in chgprot() the code
munhash(mount[c->c_mdev].m_dev, (daddr_t)(u_long)c->c_blkno);
should be changed to
munhash(mount[c->c_mdev].m_dev, c->c_blkno);
because the C compiler apparently incorrectly folds the (daddr_t) and (u_long)
together and sign extends anyway. Simply taking out the (daddr_t)(u_long)
works, although lint will probably complain about it.
------------------------------
Date: 15 Feb 85 07:57:24 GMT
From: ed@mtxinu.UUCP (Ed Gould)
Subject: Panic: munhash (and bugs in general)
> I need an explanation of what "Panic: munhash" means. We are running
> 4.2bsd and seem to crash daily with this panic.
I've seen several questions lately about this and other well-known 4.2
bugs, so I'm posting this note about the Bug List.
As a service to the 4.2 community, mt Xinu makes available the
colection of bug reports that have been mailed to Berkeley. A tape is
availatle to holders of AT&T licenses that are 32/V of newer who also
have a 4.2 license from UC. To obtain a tape, send copies of the
relevant pages (3 from the AT&T license, 2 from UC) and a check for
$110.00 (or a purchase order for $150.00) to
mt Xinu
739 Allston Way
Berkeley, CA 94710
Attn: Buglist
A paper copy (or a tape for the above price) that does not contain any
AT&T licensed source is also available to anyone who requests it,
either by US Mail to the above address or {ucbvax,decvax}!mtxinu!buglist.
Please *do not* phone for information.
NOTE: This list is a raw compilation of reports from members of the
4.2 community. Mt Xinu has not edited or verified *any* of the reports
of proposed fixes, with the exception that duplicates may be merged,
and flames without content have been removed.
--
Ed Gould mt Xinu, 739 Allston Way, Berkeley, CA 94710 USA
{ucbvax,decvax}!mtxinu!ed +1 415 644 0146
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End of Unix Technical Digest
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--
Ronald W. Heiby / ihnp4!{wnuxa!heiby|wnuxb!netnews}
AT&T Information Systems, Inc.
Lisle, IL (CU-D21)