Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 23 Dec 2001 00:52:14 +0100
From:      Nils Holland <nils@tisys.org>
To:        freebsd-stable@freebsd.org
Subject:   NFS problems in 4.5-PRERELEASE
Message-ID:  <20011223005213.A57692@tisys.org>

next in thread | raw e-mail | index | archive | help
Hi folks,
I will do some more research on this problem myself tomorrow (it's fairly
late here), but I thought I might already post a message about this today:

From what I have read, the fixes to the NFS problems that Jordan mentioned
at the beginning of last week are by now in RELENG_4. However, a updated
system (world, kernel) as of this morning causes me serious headache. There
seems to be an NFS problem, but it's highly strange in nature, and I have
not yet been able to figure it out. Anyway, here's what happens:

I copied /usr/src, /usr/obj and /usr/ports from one machine to another via
NFS. src and obj are fairly normal, ports included about 300 MB worth of
distfiles besides the ports skeleton itself.

Now, the NFS copy of src and ports does *always* work (I tried 10 times),
while copying ports seems to crash my NFS client in 2 out of three cases. The
exact panic message I get (which is probably not that useful by itself, but
I'll post it anyway) is this:

Fatal Trap 12: Page fault while in kernel mode
fault virtual address 	= 	0xe8
fault code 		= 	supervisor read, page not present
instruction pointer 	= 	0x8:0xc01b61cc
stack pointer 		= 	0x10:0xe1c73cb8
frame pointer 		= 	0x10:0xe1c73cd4
code segment 		=	base 0x0, limit 0xfffff, type 0x1b
				DPL 0, pres 1, def32 1, gran 1
processor eflags 	=	interrupt enabled, resume, IOPL = 0
current process 	=	367 (cp)
interrupt mask		=	none
trap number		=	12
panic: page fault

And now it gets interesting: This crash does *not* occur randomly, but as
my tests have shown, it occurs *always* when /usr/ports/japanese/mnews is
being copied (as shown by cp -v). To prevent misunderstandings, let
me reword this: The problem seems to occur 2 out of 3 times, but *when* it
occurs, then always at japanese/mnews, i.e. always when copying the same
file. This fact is it that makes me believe that it's actually a bug in the
code and not some hardware / random problem with my machine (if it were, it
surely wouldn't occur just at the same file every time...)

If anyone has any suggestions as far as this problem is concerned, I'd be
glad to hear about it. I'll do some research on this tomorrow and post any
interesting results. I may want to set my system up to take crash dump, but
before I do that, I'll probably try to find out if there's a pattern
somewhere, i.e. if I can crash my machine by *just* copying japanese/mnews,
or if I can successfully do several copy attempts  of /usr/ports when leaving
japanese/mnews out...

Good night
Nils 


-- 
Nils Holland
Ti Systems - FreeBSD in Tiddische, Germany
http://www.tisys.org * nils@tisys.org

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-stable" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20011223005213.A57692>