Received:  by oss.sgi.com id <S554017AbRBOASj>;
	Wed, 14 Feb 2001 16:18:39 -0800
Received: from mail.connex.com ([216.100.236.3]:30732 "EHLO
        cairn-gorm.cragtech.com") by oss.sgi.com with ESMTP
	id <S554015AbRBOASP>; Wed, 14 Feb 2001 16:18:15 -0800
Received: by cairn-gorm.cragtech.com with Internet Mail Service (5.5.2650.21)
	id <1Z0V6YBL>; Wed, 14 Feb 2001 16:14:31 -0800
Message-ID: <B14BF8753E65D211ABCA00104B301EF501BD7C4A@cairn-gorm.cragtech.com>
From:   Scott Smyth <SSmyth@Connex.com>
To:     'Steve Lord ' <lord@sgi.com>
Cc:     "'linux-xfs@oss.sgi.com'" <linux-xfs@oss.sgi.com>,
        "'dcox@maindspring.com'" <dcox@maindspring.com>
Subject: RE: For those people with IDE problems with XFS - RAID 0
Date:   Wed, 14 Feb 2001 16:14:29 -0800
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2650.21)
Content-Type: text/plain;
	charset="iso-8859-1"
Sender: owner-linux-xfs@oss.sgi.com
Precedence: bulk
Return-Path: <owner-linux-xfs@oss.sgi.com>
X-Orcpt: rfc822;linux-xfs-outgoing

Hi;

More information with regard to RAID 1 usage and 
XFS.  It appears that xfs_alloc_lookup is trying
to copy a NULL reference (0x0...) during a 
sys_write call.  I seem to only be able to reproduce
this for a RAID 1 (not for RAID 0 or RAID 5)
using UDMA IDE drives.

kdb started and the stack traced down to a NULL
reference for xfs_alloc_lookup.  It does not
happen every time, but it is very repeatable as
samba (via smbtorture) tests (via samba dbench)
cause the oops.

A different kdb oops happened from:

_page_buf_page_apply <- kio_cluster_write 
	<- sys_write

and a NULL reference.  The one was prefaced
by a kernel message of a 0-order allocation
error (page_buf.c 1369 error).

I applied Rajagopal Ananthanarayanan's 
prepare_write.patch to check its effect, but I
have seen no change.  The result is the same with
the kernel reporting:

__alloc_pages: 0-order allocation failed. 

In addition, the 2.4.2-pre3 patch with the kernel
CVS tree up to date.

thanks, Scott

-----Original Message-----
From: Steve Lord
To: Joakim Bodin
Cc: Steve Lord; Linux-XFS Mailing List
Sent: 2/14/01 1:40 PM
Subject: Re: For those people with IDE problems with XFS 

Joakim Bodin wrote:
> Steve Lord wrote:
> 
> > If you are using the development tree and ide is blowing chunks for
you,
> > can you try the following patch, it removes some of the code added
for
> > the kio patch, and backports some changes from 2.4.2-pre3 which fix
ide
> > problems. No guarantees on this one but for me it appears to be
working
> > here.
> > 
> > I think you can expect to see 2.4.2-pre3 in a day or so, it may be a
real
> > 2.4.2 by then.
> > 
> > Steve
> > 
> I just want to report that this seems to fix all the lockup problems 
> I've been having since xfs cvs moved to 2.4.1. It survives big
slocates 
> and compiles that locked it up previously. This is a P2-300, 128MB RAM

> with ide disk using udma33.
> 
> Joakim Bodin

Thanks for the feedback,

We are fixing up some issues with kiobufs and multmode ide, once this is
done I will either push this code into the 2.4.1 tree, or bring the tree
up to 2.4.2-pre3. I was hoping to see a 2.4.2 come out by now and base
the
tree on that but we are still waiting.

Steve