From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <47AC224F.4090700@gmx.de>
Date: Fri,  8 Feb 2008 10:35:11 +0100
From: Kernel Panic <cinap_lenrek@gmx.de>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US;
	rv:1.7.12) Gecko/20050915
MIME-Version: 1.0
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] VIA VT8237 SATA/RAID i/o errors, dma doesnt work
References: <54b639a7eb08c31e4ef2a6d9fd7b6a62@quanstro.net>
In-Reply-To: <54b639a7eb08c31e4ef2a6d9fd7b6a62@quanstro.net>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Topicbox-Message-UUID: 4b965e16-ead3-11e9-9d60-3106f5b1d025

Found out that the I/O errors can be triggerd by network traffic.

I was able to kill a dd by pingflooding the machine remotly :-)
This also explains why my dd script had not triggerd errors, but copying
arenas and vacing from remote machine did. I guess this is interrupt load
dependend.

I changed sdata.c to:

return SDretry if starting dmarequest fails,
return SDretry and reseting controller if dma times out,
return SDretry on request is done and error signaled,

and added a counter that resets the controller if a request
was 1000 times retried...

The machine ran the whole night with bodth drives in DMA and heavy load.
vacing, pingflooded from outside, ddtest on both drives and still alive! :-)

futher testing this weekend...

cinap